1 | /*****************************************************************************\ |
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2 | * Computer Algebra System SINGULAR |
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3 | \*****************************************************************************/ |
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4 | /** @file facHensel.cc |
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5 | * |
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6 | * This file implements functions to lift factors via Hensel lifting and |
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7 | * functions for modular multiplication and division with remainder. |
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8 | * |
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9 | * ABSTRACT: Hensel lifting is described in "Efficient Multivariate |
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10 | * Factorization over Finite Fields" by L. Bernardin & M. Monagon. Division with |
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11 | * remainder is described in "Fast Recursive Division" by C. Burnikel and |
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12 | * J. Ziegler. Karatsuba multiplication is described in "Modern Computer |
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13 | * Algebra" by J. von zur Gathen and J. Gerhard. |
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14 | * |
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15 | * @author Martin Lee |
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16 | * |
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17 | * @internal @version \$Id$ |
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18 | * |
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19 | **/ |
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20 | /*****************************************************************************/ |
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21 | |
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22 | #include "assert.h" |
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23 | #include "debug.h" |
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24 | #include "timing.h" |
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25 | |
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26 | #include "facHensel.h" |
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27 | #include "cf_util.h" |
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28 | #include "fac_util.h" |
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29 | #include "cf_algorithm.h" |
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30 | |
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31 | #ifdef HAVE_NTL |
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32 | #include <NTL/lzz_pEX.h> |
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33 | #include "NTLconvert.h" |
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34 | |
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35 | static inline |
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36 | CanonicalForm |
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37 | mulNTL (const CanonicalForm& F, const CanonicalForm& G) |
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38 | { |
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39 | if (F.inCoeffDomain() || G.inCoeffDomain()) |
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40 | return F*G; |
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41 | ASSERT (F.isUnivariate() && G.isUnivariate(), "expected univariate polys"); |
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42 | ASSERT (F.level() == G.level(), "expected polys of same level"); |
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43 | if (CFFactory::gettype() == GaloisFieldDomain) |
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44 | return F*G; |
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45 | zz_p::init (getCharacteristic()); |
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46 | Variable alpha; |
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47 | CanonicalForm result; |
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48 | if (hasFirstAlgVar (F, alpha) || hasFirstAlgVar (G, alpha)) |
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49 | { |
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50 | zz_pX NTLMipo= convertFacCF2NTLzzpX (getMipo (alpha)); |
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51 | zz_pE::init (NTLMipo); |
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52 | zz_pEX NTLF= convertFacCF2NTLzz_pEX (F, NTLMipo); |
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53 | zz_pEX NTLG= convertFacCF2NTLzz_pEX (G, NTLMipo); |
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54 | mul (NTLF, NTLF, NTLG); |
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55 | result= convertNTLzz_pEX2CF(NTLF, F.mvar(), alpha); |
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56 | } |
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57 | else |
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58 | { |
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59 | zz_pX NTLF= convertFacCF2NTLzzpX (F); |
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60 | zz_pX NTLG= convertFacCF2NTLzzpX (G); |
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61 | mul (NTLF, NTLF, NTLG); |
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62 | result= convertNTLzzpX2CF(NTLF, F.mvar()); |
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63 | } |
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64 | return result; |
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65 | } |
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66 | |
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67 | static inline |
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68 | CanonicalForm |
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69 | modNTL (const CanonicalForm& F, const CanonicalForm& G) |
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70 | { |
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71 | if (F.inCoeffDomain() && G.isUnivariate()) |
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72 | return F; |
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73 | else if (F.inCoeffDomain() && G.inCoeffDomain()) |
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74 | return mod (F, G); |
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75 | else if (F.isUnivariate() && G.inCoeffDomain()) |
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76 | return mod (F,G); |
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77 | |
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78 | ASSERT (F.isUnivariate() && G.isUnivariate(), "expected univariate polys"); |
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79 | ASSERT (F.level() == G.level(), "expected polys of same level"); |
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80 | if (CFFactory::gettype() == GaloisFieldDomain) |
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81 | return mod (F, G); |
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82 | zz_p::init (getCharacteristic()); |
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83 | Variable alpha; |
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84 | CanonicalForm result; |
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85 | if (hasFirstAlgVar (F, alpha) || hasFirstAlgVar (G, alpha)) |
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86 | { |
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87 | zz_pX NTLMipo= convertFacCF2NTLzzpX(getMipo (alpha)); |
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88 | zz_pE::init (NTLMipo); |
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89 | zz_pEX NTLF= convertFacCF2NTLzz_pEX (F, NTLMipo); |
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90 | zz_pEX NTLG= convertFacCF2NTLzz_pEX (G, NTLMipo); |
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91 | rem (NTLF, NTLF, NTLG); |
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92 | result= convertNTLzz_pEX2CF(NTLF, F.mvar(), alpha); |
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93 | } |
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94 | else |
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95 | { |
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96 | zz_pX NTLF= convertFacCF2NTLzzpX (F); |
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97 | zz_pX NTLG= convertFacCF2NTLzzpX (G); |
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98 | rem (NTLF, NTLF, NTLG); |
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99 | result= convertNTLzzpX2CF(NTLF, F.mvar()); |
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100 | } |
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101 | return result; |
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102 | } |
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103 | |
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104 | static inline |
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105 | CanonicalForm |
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106 | divNTL (const CanonicalForm& F, const CanonicalForm& G) |
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107 | { |
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108 | if (F.inCoeffDomain() && G.isUnivariate()) |
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109 | return F; |
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110 | else if (F.inCoeffDomain() && G.inCoeffDomain()) |
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111 | return div (F, G); |
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112 | else if (F.isUnivariate() && G.inCoeffDomain()) |
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113 | return div (F,G); |
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114 | |
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115 | ASSERT (F.isUnivariate() && G.isUnivariate(), "expected univariate polys"); |
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116 | ASSERT (F.level() == G.level(), "expected polys of same level"); |
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117 | if (CFFactory::gettype() == GaloisFieldDomain) |
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118 | return div (F, G); |
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119 | zz_p::init (getCharacteristic()); |
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120 | Variable alpha; |
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121 | CanonicalForm result; |
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122 | if (hasFirstAlgVar (F, alpha) || hasFirstAlgVar (G, alpha)) |
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123 | { |
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124 | zz_pX NTLMipo= convertFacCF2NTLzzpX(getMipo (alpha)); |
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125 | zz_pE::init (NTLMipo); |
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126 | zz_pEX NTLF= convertFacCF2NTLzz_pEX (F, NTLMipo); |
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127 | zz_pEX NTLG= convertFacCF2NTLzz_pEX (G, NTLMipo); |
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128 | div (NTLF, NTLF, NTLG); |
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129 | result= convertNTLzz_pEX2CF(NTLF, F.mvar(), alpha); |
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130 | } |
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131 | else |
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132 | { |
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133 | zz_pX NTLF= convertFacCF2NTLzzpX (F); |
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134 | zz_pX NTLG= convertFacCF2NTLzzpX (G); |
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135 | div (NTLF, NTLF, NTLG); |
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136 | result= convertNTLzzpX2CF(NTLF, F.mvar()); |
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137 | } |
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138 | return result; |
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139 | } |
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140 | |
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141 | /*static inline |
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142 | void |
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143 | divremNTL (const CanonicalForm& F, const CanonicalForm& G, CanonicalForm& Q, |
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144 | CanonicalForm& R) |
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145 | { |
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146 | if (F.inCoeffDomain() && G.isUnivariate()) |
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147 | { |
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148 | R= F; |
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149 | Q= 0; |
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150 | } |
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151 | else if (F.inCoeffDomain() && G.inCoeffDomain()) |
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152 | { |
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153 | divrem (F, G, Q, R); |
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154 | return; |
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155 | } |
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156 | else if (F.isUnivariate() && G.inCoeffDomain()) |
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157 | { |
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158 | divrem (F, G, Q, R); |
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159 | return; |
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160 | } |
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161 | |
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162 | ASSERT (F.isUnivariate() && G.isUnivariate(), "expected univariate polys"); |
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163 | ASSERT (F.level() == G.level(), "expected polys of same level"); |
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164 | if (CFFactory::gettype() == GaloisFieldDomain) |
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165 | { |
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166 | divrem (F, G, Q, R); |
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167 | return; |
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168 | } |
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169 | zz_p::init (getCharacteristic()); |
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170 | Variable alpha; |
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171 | CanonicalForm result; |
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172 | if (hasFirstAlgVar (F, alpha) || hasFirstAlgVar (G, alpha)) |
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173 | { |
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174 | zz_pX NTLMipo= convertFacCF2NTLzzpX(getMipo (alpha)); |
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175 | zz_pE::init (NTLMipo); |
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176 | zz_pEX NTLF= convertFacCF2NTLzz_pEX (F, NTLMipo); |
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177 | zz_pEX NTLG= convertFacCF2NTLzz_pEX (G, NTLMipo); |
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178 | zz_pEX NTLQ; |
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179 | zz_pEX NTLR; |
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180 | DivRem (NTLQ, NTLR, NTLF, NTLG); |
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181 | Q= convertNTLzz_pEX2CF(NTLQ, F.mvar(), alpha); |
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182 | R= convertNTLzz_pEX2CF(NTLR, F.mvar(), alpha); |
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183 | return; |
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184 | } |
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185 | else |
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186 | { |
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187 | zz_pX NTLF= convertFacCF2NTLzzpX (F); |
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188 | zz_pX NTLG= convertFacCF2NTLzzpX (G); |
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189 | zz_pX NTLQ; |
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190 | zz_pX NTLR; |
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191 | DivRem (NTLQ, NTLR, NTLF, NTLG); |
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192 | Q= convertNTLzzpX2CF(NTLQ, F.mvar()); |
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193 | R= convertNTLzzpX2CF(NTLR, F.mvar()); |
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194 | return; |
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195 | } |
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196 | }*/ |
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197 | |
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198 | CanonicalForm mod (const CanonicalForm& F, const CFList& M) |
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199 | { |
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200 | CanonicalForm A= F; |
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201 | for (CFListIterator i= M; i.hasItem(); i++) |
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202 | A= mod (A, i.getItem()); |
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203 | return A; |
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204 | } |
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205 | |
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206 | CanonicalForm mulMod2 (const CanonicalForm& A, const CanonicalForm& B, |
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207 | const CanonicalForm& M) |
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208 | { |
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209 | if (A.isZero() || B.isZero()) |
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210 | return 0; |
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211 | |
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212 | ASSERT (M.isUnivariate(), "M must be univariate"); |
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213 | |
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214 | CanonicalForm F= mod (A, M); |
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215 | CanonicalForm G= mod (B, M); |
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216 | if (F.inCoeffDomain() || G.inCoeffDomain()) |
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217 | return F*G; |
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218 | Variable y= M.mvar(); |
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219 | int degF= degree (F, y); |
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220 | int degG= degree (G, y); |
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221 | |
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222 | if ((degF < 1 && degG < 1) && (F.isUnivariate() && G.isUnivariate()) && |
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223 | (F.level() == G.level())) |
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224 | { |
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225 | CanonicalForm result= mulNTL (F, G); |
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226 | return mod (result, M); |
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227 | } |
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228 | else if (degF <= 1 && degG <= 1) |
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229 | { |
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230 | CanonicalForm result= F*G; |
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231 | return mod (result, M); |
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232 | } |
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233 | |
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234 | int m= (int) ceil (degree (M)/2.0); |
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235 | if (degF >= m || degG >= m) |
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236 | { |
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237 | CanonicalForm MLo= power (y, m); |
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238 | CanonicalForm MHi= power (y, degree (M) - m); |
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239 | CanonicalForm F0= mod (F, MLo); |
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240 | CanonicalForm F1= div (F, MLo); |
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241 | CanonicalForm G0= mod (G, MLo); |
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242 | CanonicalForm G1= div (G, MLo); |
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243 | CanonicalForm F0G1= mulMod2 (F0, G1, MHi); |
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244 | CanonicalForm F1G0= mulMod2 (F1, G0, MHi); |
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245 | CanonicalForm F0G0= mulMod2 (F0, G0, M); |
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246 | return F0G0 + MLo*(F0G1 + F1G0); |
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247 | } |
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248 | else |
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249 | { |
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250 | m= (int) ceil (tmax (degF, degG)/2.0); |
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251 | CanonicalForm yToM= power (y, m); |
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252 | CanonicalForm F0= mod (F, yToM); |
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253 | CanonicalForm F1= div (F, yToM); |
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254 | CanonicalForm G0= mod (G, yToM); |
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255 | CanonicalForm G1= div (G, yToM); |
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256 | CanonicalForm H00= mulMod2 (F0, G0, M); |
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257 | CanonicalForm H11= mulMod2 (F1, G1, M); |
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258 | CanonicalForm H01= mulMod2 (F0 + F1, G0 + G1, M); |
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259 | return H11*yToM*yToM + (H01 - H11 - H00)*yToM + H00; |
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260 | } |
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261 | DEBOUTLN (cerr, "fatal end in mulMod2"); |
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262 | } |
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263 | |
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264 | CanonicalForm mulMod (const CanonicalForm& A, const CanonicalForm& B, |
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265 | const CFList& MOD) |
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266 | { |
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267 | if (A.isZero() || B.isZero()) |
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268 | return 0; |
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269 | |
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270 | if (MOD.length() == 1) |
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271 | return mulMod2 (A, B, MOD.getLast()); |
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272 | |
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273 | CanonicalForm M= MOD.getLast(); |
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274 | CanonicalForm F= mod (A, M); |
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275 | CanonicalForm G= mod (B, M); |
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276 | if (F.inCoeffDomain() || G.inCoeffDomain()) |
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277 | return F*G; |
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278 | Variable y= M.mvar(); |
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279 | int degF= degree (F, y); |
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280 | int degG= degree (G, y); |
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281 | |
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282 | if ((degF <= 1 && F.level() <= M.level()) && |
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283 | (degG <= 1 && G.level() <= M.level())) |
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284 | { |
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285 | CFList buf= MOD; |
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286 | buf.removeLast(); |
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287 | if (degF == 1 && degG == 1) |
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288 | { |
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289 | CanonicalForm F0= mod (F, y); |
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290 | CanonicalForm F1= div (F, y); |
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291 | CanonicalForm G0= mod (G, y); |
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292 | CanonicalForm G1= div (G, y); |
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293 | if (degree (M) > 2) |
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294 | { |
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295 | CanonicalForm H00= mulMod (F0, G0, buf); |
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296 | CanonicalForm H11= mulMod (F1, G1, buf); |
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297 | CanonicalForm H01= mulMod (F0 + F1, G0 + G1, buf); |
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298 | return H11*y*y + (H01 - H00 - H11)*y + H00; |
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299 | } |
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300 | else //here degree (M) == 2 |
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301 | { |
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302 | buf.append (y); |
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303 | CanonicalForm F0G1= mulMod (F0, G1, buf); |
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304 | CanonicalForm F1G0= mulMod (F1, G0, buf); |
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305 | CanonicalForm F0G0= mulMod (F0, G0, MOD); |
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306 | CanonicalForm result= F0G0 + y*(F0G1 + F1G0); |
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307 | return result; |
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308 | } |
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309 | } |
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310 | else if (degF == 1 && degG == 0) |
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311 | return mulMod (div (F, y), G, buf)*y + mulMod (mod (F, y), G, buf); |
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312 | else if (degF == 0 && degG == 1) |
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313 | return mulMod (div (G, y), F, buf)*y + mulMod (mod (G, y), F, buf); |
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314 | else |
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315 | return mulMod (F, G, buf); |
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316 | } |
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317 | int m= (int) ceil (degree (M)/2.0); |
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318 | if (degF >= m || degG >= m) |
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319 | { |
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320 | CanonicalForm MLo= power (y, m); |
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321 | CanonicalForm MHi= power (y, degree (M) - m); |
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322 | CanonicalForm F0= mod (F, MLo); |
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323 | CanonicalForm F1= div (F, MLo); |
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324 | CanonicalForm G0= mod (G, MLo); |
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325 | CanonicalForm G1= div (G, MLo); |
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326 | CFList buf= MOD; |
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327 | buf.removeLast(); |
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328 | buf.append (MHi); |
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329 | CanonicalForm F0G1= mulMod (F0, G1, buf); |
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330 | CanonicalForm F1G0= mulMod (F1, G0, buf); |
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331 | CanonicalForm F0G0= mulMod (F0, G0, MOD); |
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332 | return F0G0 + MLo*(F0G1 + F1G0); |
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333 | } |
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334 | else |
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335 | { |
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336 | m= (int) ceil (tmax (degF, degG)/2.0); |
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337 | CanonicalForm yToM= power (y, m); |
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338 | CanonicalForm F0= mod (F, yToM); |
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339 | CanonicalForm F1= div (F, yToM); |
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340 | CanonicalForm G0= mod (G, yToM); |
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341 | CanonicalForm G1= div (G, yToM); |
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342 | CanonicalForm H00= mulMod (F0, G0, MOD); |
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343 | CanonicalForm H11= mulMod (F1, G1, MOD); |
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344 | CanonicalForm H01= mulMod (F0 + F1, G0 + G1, MOD); |
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345 | return H11*yToM*yToM + (H01 - H11 - H00)*yToM + H00; |
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346 | } |
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347 | DEBOUTLN (cerr, "fatal end in mulMod"); |
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348 | } |
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349 | |
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350 | CanonicalForm prodMod (const CFList& L, const CanonicalForm& M) |
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351 | { |
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352 | if (L.isEmpty()) |
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353 | return 1; |
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354 | int l= L.length(); |
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355 | if (l == 1) |
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356 | return mod (L.getFirst(), M); |
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357 | else if (l == 2) { |
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358 | CanonicalForm result= mulMod2 (L.getFirst(), L.getLast(), M); |
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359 | return result; |
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360 | } |
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361 | else |
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362 | { |
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363 | l /= 2; |
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364 | CFList tmp1, tmp2; |
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365 | CFListIterator i= L; |
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366 | CanonicalForm buf1, buf2; |
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367 | for (int j= 1; j <= l; j++, i++) |
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368 | tmp1.append (i.getItem()); |
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369 | tmp2= Difference (L, tmp1); |
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370 | buf1= prodMod (tmp1, M); |
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371 | buf2= prodMod (tmp2, M); |
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372 | CanonicalForm result= mulMod2 (buf1, buf2, M); |
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373 | return result; |
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374 | } |
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375 | } |
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376 | |
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377 | CanonicalForm prodMod (const CFList& L, const CFList& M) |
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378 | { |
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379 | if (L.isEmpty()) |
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380 | return 1; |
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381 | else if (L.length() == 1) |
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382 | return L.getFirst(); |
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383 | else if (L.length() == 2) |
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384 | return mulMod (L.getFirst(), L.getLast(), M); |
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385 | else |
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386 | { |
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387 | int l= L.length()/2; |
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388 | CFListIterator i= L; |
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389 | CFList tmp1, tmp2; |
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390 | CanonicalForm buf1, buf2; |
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391 | for (int j= 1; j <= l; j++, i++) |
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392 | tmp1.append (i.getItem()); |
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393 | tmp2= Difference (L, tmp1); |
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394 | buf1= prodMod (tmp1, M); |
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395 | buf2= prodMod (tmp2, M); |
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396 | return mulMod (buf1, buf2, M); |
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397 | } |
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398 | } |
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399 | |
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400 | |
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401 | CanonicalForm reverse (const CanonicalForm& F, int d) |
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402 | { |
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403 | if (d == 0) |
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404 | return F; |
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405 | CanonicalForm A= F; |
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406 | Variable y= F.mvar(); |
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407 | Variable x= Variable (1); |
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408 | A= swapvar (A, x, y); |
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409 | CanonicalForm result= 0; |
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410 | CFIterator i= A; |
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411 | while (d - i.exp() < 0) |
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412 | i++; |
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413 | |
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414 | for (; i.hasTerms() && (d - i.exp() >= 0); i++) |
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415 | result += swapvar (i.coeff(),x,y)*power (x, d - i.exp()); |
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416 | return result; |
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417 | } |
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418 | |
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419 | CanonicalForm |
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420 | newtonInverse (const CanonicalForm& F, const int n, const CanonicalForm& M) |
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421 | { |
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422 | int l= ilog2(n); |
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423 | |
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424 | CanonicalForm g= mod (F, M)[0] [0]; |
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425 | |
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426 | ASSERT (!g.isZero(), "expected a unit"); |
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427 | |
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428 | Variable alpha; |
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429 | |
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430 | if (!g.isOne()) |
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431 | g = 1/g; |
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432 | Variable x= Variable (1); |
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433 | CanonicalForm result; |
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434 | int exp= 0; |
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435 | if (n & 1) |
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436 | { |
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437 | result= g; |
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438 | exp= 1; |
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439 | } |
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440 | CanonicalForm h; |
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441 | |
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442 | for (int i= 1; i <= l; i++) |
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443 | { |
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444 | h= mulMod2 (g, mod (F, power (x, (1 << i))), M); |
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445 | h= mod (h, power (x, (1 << i)) - 1); |
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446 | h= div (h, power (x, (1 << (i - 1)))); |
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447 | h= mod (h, M); |
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448 | g -= power (x, (1 << (i - 1)))* |
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449 | mod (mulMod2 (g, h, M), power (x, (1 << (i - 1)))); |
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450 | |
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451 | if (n & (1 << i)) |
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452 | { |
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453 | if (exp) |
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454 | { |
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455 | h= mulMod2 (result, mod (F, power (x, exp + (1 << i))), M); |
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456 | h= mod (h, power (x, exp + (1 << i)) - 1); |
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457 | h= div (h, power (x, exp)); |
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458 | h= mod (h, M); |
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459 | result -= power(x, exp)*mod (mulMod2 (g, h, M), |
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460 | power (x, (1 << i))); |
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461 | exp += (1 << i); |
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462 | } |
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463 | else |
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464 | { |
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465 | exp= (1 << i); |
---|
466 | result= g; |
---|
467 | } |
---|
468 | } |
---|
469 | } |
---|
470 | |
---|
471 | return result; |
---|
472 | } |
---|
473 | |
---|
474 | CanonicalForm |
---|
475 | newtonDiv (const CanonicalForm& F, const CanonicalForm& G, const CanonicalForm& |
---|
476 | M) |
---|
477 | { |
---|
478 | ASSERT (getCharacteristic() > 0, "positive characteristic expected"); |
---|
479 | ASSERT (CFFactory::gettype() != GaloisFieldDomain, "no GF expected"); |
---|
480 | |
---|
481 | CanonicalForm A= mod (F, M); |
---|
482 | CanonicalForm B= mod (G, M); |
---|
483 | |
---|
484 | Variable x= Variable (1); |
---|
485 | int degA= degree (A, x); |
---|
486 | int degB= degree (B, x); |
---|
487 | int m= degA - degB; |
---|
488 | if (m < 0) |
---|
489 | return 0; |
---|
490 | |
---|
491 | CanonicalForm Q; |
---|
492 | if (degB <= 1) |
---|
493 | { |
---|
494 | CanonicalForm R; |
---|
495 | divrem2 (A, B, Q, R, M); |
---|
496 | } |
---|
497 | else |
---|
498 | { |
---|
499 | CanonicalForm R= reverse (A, degA); |
---|
500 | CanonicalForm revB= reverse (B, degB); |
---|
501 | revB= newtonInverse (revB, m + 1, M); |
---|
502 | Q= mulMod2 (R, revB, M); |
---|
503 | Q= mod (Q, power (x, m + 1)); |
---|
504 | Q= reverse (Q, m); |
---|
505 | } |
---|
506 | |
---|
507 | return Q; |
---|
508 | } |
---|
509 | |
---|
510 | void |
---|
511 | newtonDivrem (const CanonicalForm& F, const CanonicalForm& G, CanonicalForm& Q, |
---|
512 | CanonicalForm& R, const CanonicalForm& M) |
---|
513 | { |
---|
514 | CanonicalForm A= mod (F, M); |
---|
515 | CanonicalForm B= mod (G, M); |
---|
516 | Variable x= Variable (1); |
---|
517 | int degA= degree (A, x); |
---|
518 | int degB= degree (B, x); |
---|
519 | int m= degA - degB; |
---|
520 | |
---|
521 | if (m < 0) |
---|
522 | { |
---|
523 | R= A; |
---|
524 | Q= 0; |
---|
525 | return; |
---|
526 | } |
---|
527 | |
---|
528 | if (degB <= 1) |
---|
529 | { |
---|
530 | divrem2 (A, B, Q, R, M); |
---|
531 | } |
---|
532 | else |
---|
533 | { |
---|
534 | R= reverse (A, degA); |
---|
535 | |
---|
536 | CanonicalForm revB= reverse (B, degB); |
---|
537 | revB= newtonInverse (revB, m + 1, M); |
---|
538 | Q= mulMod2 (R, revB, M); |
---|
539 | |
---|
540 | Q= mod (Q, power (x, m + 1)); |
---|
541 | Q= reverse (Q, m); |
---|
542 | |
---|
543 | R= A - mulMod2 (Q, B, M); |
---|
544 | } |
---|
545 | } |
---|
546 | |
---|
547 | static inline |
---|
548 | CFList split (const CanonicalForm& F, const int m, const Variable& x) |
---|
549 | { |
---|
550 | CanonicalForm A= F; |
---|
551 | CanonicalForm buf= 0; |
---|
552 | bool swap= false; |
---|
553 | if (degree (A, x) <= 0) |
---|
554 | return CFList(A); |
---|
555 | else if (x.level() != A.level()) |
---|
556 | { |
---|
557 | swap= true; |
---|
558 | A= swapvar (A, x, A.mvar()); |
---|
559 | } |
---|
560 | |
---|
561 | int j= (int) floor ((double) degree (A)/ m); |
---|
562 | CFList result; |
---|
563 | CFIterator i= A; |
---|
564 | for (; j >= 0; j--) |
---|
565 | { |
---|
566 | while (i.hasTerms() && i.exp() - j*m >= 0) |
---|
567 | { |
---|
568 | if (swap) |
---|
569 | buf += i.coeff()*power (A.mvar(), i.exp() - j*m); |
---|
570 | else |
---|
571 | buf += i.coeff()*power (x, i.exp() - j*m); |
---|
572 | i++; |
---|
573 | } |
---|
574 | if (swap) |
---|
575 | result.append (swapvar (buf, x, F.mvar())); |
---|
576 | else |
---|
577 | result.append (buf); |
---|
578 | buf= 0; |
---|
579 | } |
---|
580 | return result; |
---|
581 | } |
---|
582 | |
---|
583 | static inline |
---|
584 | void divrem32 (const CanonicalForm& F, const CanonicalForm& G, CanonicalForm& Q, |
---|
585 | CanonicalForm& R, const CFList& M); |
---|
586 | |
---|
587 | static inline |
---|
588 | void divrem21 (const CanonicalForm& F, const CanonicalForm& G, CanonicalForm& Q, |
---|
589 | CanonicalForm& R, const CFList& M) |
---|
590 | { |
---|
591 | CanonicalForm A= mod (F, M); |
---|
592 | CanonicalForm B= mod (G, M); |
---|
593 | Variable x= Variable (1); |
---|
594 | int degB= degree (B, x); |
---|
595 | int degA= degree (A, x); |
---|
596 | if (degA < degB) |
---|
597 | { |
---|
598 | Q= 0; |
---|
599 | R= A; |
---|
600 | return; |
---|
601 | } |
---|
602 | ASSERT (2*degB > degA, "expected degree (F, 1) < 2*degree (G, 1)"); |
---|
603 | if (degB < 1) |
---|
604 | { |
---|
605 | divrem (A, B, Q, R); |
---|
606 | Q= mod (Q, M); |
---|
607 | R= mod (R, M); |
---|
608 | return; |
---|
609 | } |
---|
610 | |
---|
611 | int m= (int) ceil ((double) (degB + 1)/2.0) + 1; |
---|
612 | CFList splitA= split (A, m, x); |
---|
613 | CFList splitB= split (B, m, x); |
---|
614 | if (splitA.length() == 3) |
---|
615 | splitA.insert (0); |
---|
616 | if (splitA.length() == 2) |
---|
617 | { |
---|
618 | splitA.insert (0); |
---|
619 | splitA.insert (0); |
---|
620 | } |
---|
621 | if (splitA.length() == 1) |
---|
622 | { |
---|
623 | splitA.insert (0); |
---|
624 | splitA.insert (0); |
---|
625 | splitA.insert (0); |
---|
626 | } |
---|
627 | |
---|
628 | CanonicalForm xToM= power (x, m); |
---|
629 | |
---|
630 | CFListIterator i= splitA; |
---|
631 | CanonicalForm H= i.getItem(); |
---|
632 | i++; |
---|
633 | H *= xToM; |
---|
634 | H += i.getItem(); |
---|
635 | i++; |
---|
636 | H *= xToM; |
---|
637 | H += i.getItem(); |
---|
638 | i++; |
---|
639 | |
---|
640 | divrem32 (H, B, Q, R, M); |
---|
641 | |
---|
642 | CFList splitR= split (R, m, x); |
---|
643 | if (splitR.length() == 1) |
---|
644 | splitR.insert (0); |
---|
645 | |
---|
646 | H= splitR.getFirst(); |
---|
647 | H *= xToM; |
---|
648 | H += splitR.getLast(); |
---|
649 | H *= xToM; |
---|
650 | H += i.getItem(); |
---|
651 | |
---|
652 | CanonicalForm bufQ; |
---|
653 | divrem32 (H, B, bufQ, R, M); |
---|
654 | |
---|
655 | Q *= xToM; |
---|
656 | Q += bufQ; |
---|
657 | return; |
---|
658 | } |
---|
659 | |
---|
660 | static inline |
---|
661 | void divrem32 (const CanonicalForm& F, const CanonicalForm& G, CanonicalForm& Q, |
---|
662 | CanonicalForm& R, const CFList& M) |
---|
663 | { |
---|
664 | CanonicalForm A= mod (F, M); |
---|
665 | CanonicalForm B= mod (G, M); |
---|
666 | Variable x= Variable (1); |
---|
667 | int degB= degree (B, x); |
---|
668 | int degA= degree (A, x); |
---|
669 | if (degA < degB) |
---|
670 | { |
---|
671 | Q= 0; |
---|
672 | R= A; |
---|
673 | return; |
---|
674 | } |
---|
675 | ASSERT (3*(degB/2) > degA, "expected degree (F, 1) < 3*(degree (G, 1)/2)"); |
---|
676 | if (degB < 1) |
---|
677 | { |
---|
678 | divrem (A, B, Q, R); |
---|
679 | Q= mod (Q, M); |
---|
680 | R= mod (R, M); |
---|
681 | return; |
---|
682 | } |
---|
683 | int m= (int) ceil ((double) (degB + 1)/ 2.0); |
---|
684 | |
---|
685 | CFList splitA= split (A, m, x); |
---|
686 | CFList splitB= split (B, m, x); |
---|
687 | |
---|
688 | if (splitA.length() == 2) |
---|
689 | { |
---|
690 | splitA.insert (0); |
---|
691 | } |
---|
692 | if (splitA.length() == 1) |
---|
693 | { |
---|
694 | splitA.insert (0); |
---|
695 | splitA.insert (0); |
---|
696 | } |
---|
697 | CanonicalForm xToM= power (x, m); |
---|
698 | |
---|
699 | CanonicalForm H; |
---|
700 | CFListIterator i= splitA; |
---|
701 | i++; |
---|
702 | |
---|
703 | if (degree (splitA.getFirst(), x) < degree (splitB.getFirst(), x)) |
---|
704 | { |
---|
705 | H= splitA.getFirst()*xToM + i.getItem(); |
---|
706 | divrem21 (H, splitB.getFirst(), Q, R, M); |
---|
707 | } |
---|
708 | else |
---|
709 | { |
---|
710 | R= splitA.getFirst()*xToM + i.getItem() + splitB.getFirst() - |
---|
711 | splitB.getFirst()*xToM; |
---|
712 | Q= xToM - 1; |
---|
713 | } |
---|
714 | |
---|
715 | H= mulMod (Q, splitB.getLast(), M); |
---|
716 | |
---|
717 | R= R*xToM + splitA.getLast() - H; |
---|
718 | |
---|
719 | while (degree (R, x) >= degB) |
---|
720 | { |
---|
721 | xToM= power (x, degree (R, x) - degB); |
---|
722 | Q += LC (R, x)*xToM; |
---|
723 | R -= mulMod (LC (R, x), B, M)*xToM; |
---|
724 | Q= mod (Q, M); |
---|
725 | R= mod (R, M); |
---|
726 | } |
---|
727 | |
---|
728 | return; |
---|
729 | } |
---|
730 | |
---|
731 | void divrem2 (const CanonicalForm& F, const CanonicalForm& G, CanonicalForm& Q, |
---|
732 | CanonicalForm& R, const CanonicalForm& M) |
---|
733 | { |
---|
734 | CanonicalForm A= mod (F, M); |
---|
735 | CanonicalForm B= mod (G, M); |
---|
736 | Variable x= Variable (1); |
---|
737 | int degB= degree (B, x); |
---|
738 | if (degB > degree (A, x)) |
---|
739 | { |
---|
740 | Q= 0; |
---|
741 | R= A; |
---|
742 | return; |
---|
743 | } |
---|
744 | |
---|
745 | CFList splitA= split (A, degB, x); |
---|
746 | |
---|
747 | CanonicalForm xToDegB= power (x, degB); |
---|
748 | CanonicalForm H, bufQ; |
---|
749 | Q= 0; |
---|
750 | CFListIterator i= splitA; |
---|
751 | H= i.getItem()*xToDegB; |
---|
752 | i++; |
---|
753 | H += i.getItem(); |
---|
754 | CFList buf; |
---|
755 | while (i.hasItem()) |
---|
756 | { |
---|
757 | buf= CFList (M); |
---|
758 | divrem21 (H, B, bufQ, R, buf); |
---|
759 | i++; |
---|
760 | if (i.hasItem()) |
---|
761 | H= R*xToDegB + i.getItem(); |
---|
762 | Q *= xToDegB; |
---|
763 | Q += bufQ; |
---|
764 | } |
---|
765 | return; |
---|
766 | } |
---|
767 | |
---|
768 | void divrem (const CanonicalForm& F, const CanonicalForm& G, CanonicalForm& Q, |
---|
769 | CanonicalForm& R, const CFList& MOD) |
---|
770 | { |
---|
771 | CanonicalForm A= mod (F, MOD); |
---|
772 | CanonicalForm B= mod (G, MOD); |
---|
773 | Variable x= Variable (1); |
---|
774 | int degB= degree (B, x); |
---|
775 | if (degB > degree (A, x)) |
---|
776 | { |
---|
777 | Q= 0; |
---|
778 | R= A; |
---|
779 | return; |
---|
780 | } |
---|
781 | |
---|
782 | if (degB == 0) |
---|
783 | { |
---|
784 | divrem (A, B, Q, R); |
---|
785 | Q= mod (Q, MOD); |
---|
786 | R= mod (R, MOD); |
---|
787 | return; |
---|
788 | } |
---|
789 | CFList splitA= split (A, degB, x); |
---|
790 | |
---|
791 | CanonicalForm xToDegB= power (x, degB); |
---|
792 | CanonicalForm H, bufQ; |
---|
793 | Q= 0; |
---|
794 | CFListIterator i= splitA; |
---|
795 | H= i.getItem()*xToDegB; |
---|
796 | i++; |
---|
797 | H += i.getItem(); |
---|
798 | while (i.hasItem()) |
---|
799 | { |
---|
800 | divrem21 (H, B, bufQ, R, MOD); |
---|
801 | i++; |
---|
802 | if (i.hasItem()) |
---|
803 | H= R*xToDegB + i.getItem(); |
---|
804 | Q *= xToDegB; |
---|
805 | Q += bufQ; |
---|
806 | } |
---|
807 | return; |
---|
808 | } |
---|
809 | |
---|
810 | void sortList (CFList& list, const Variable& x) |
---|
811 | { |
---|
812 | int l= 1; |
---|
813 | int k= 1; |
---|
814 | CanonicalForm buf; |
---|
815 | CFListIterator m; |
---|
816 | for (CFListIterator i= list; l <= list.length(); i++, l++) |
---|
817 | { |
---|
818 | for (CFListIterator j= list; k <= list.length() - l; k++) |
---|
819 | { |
---|
820 | m= j; |
---|
821 | m++; |
---|
822 | if (degree (j.getItem(), x) > degree (m.getItem(), x)) |
---|
823 | { |
---|
824 | buf= m.getItem(); |
---|
825 | m.getItem()= j.getItem(); |
---|
826 | j.getItem()= buf; |
---|
827 | j++; |
---|
828 | j.getItem()= m.getItem(); |
---|
829 | } |
---|
830 | else |
---|
831 | j++; |
---|
832 | } |
---|
833 | k= 1; |
---|
834 | } |
---|
835 | } |
---|
836 | |
---|
837 | static inline |
---|
838 | CFList diophantine (const CanonicalForm& F, const CFList& factors) |
---|
839 | { |
---|
840 | CanonicalForm buf1, buf2, buf3, S, T; |
---|
841 | CFListIterator i= factors; |
---|
842 | CFList result; |
---|
843 | if (i.hasItem()) |
---|
844 | i++; |
---|
845 | buf1= F/factors.getFirst(); |
---|
846 | buf2= divNTL (F, i.getItem()); |
---|
847 | buf3= extgcd (buf1, buf2, S, T); |
---|
848 | result.append (S); |
---|
849 | result.append (T); |
---|
850 | if (i.hasItem()) |
---|
851 | i++; |
---|
852 | for (; i.hasItem(); i++) |
---|
853 | { |
---|
854 | buf1= divNTL (F, i.getItem()); |
---|
855 | buf3= extgcd (buf3, buf1, S, T); |
---|
856 | CFListIterator k= factors; |
---|
857 | for (CFListIterator j= result; j.hasItem(); j++, k++) |
---|
858 | { |
---|
859 | j.getItem()= mulNTL (j.getItem(), S); |
---|
860 | j.getItem()= modNTL (j.getItem(), k.getItem()); |
---|
861 | } |
---|
862 | result.append (T); |
---|
863 | } |
---|
864 | return result; |
---|
865 | } |
---|
866 | |
---|
867 | void |
---|
868 | henselStep12 (const CanonicalForm& F, const CFList& factors, |
---|
869 | CFArray& bufFactors, const CFList& diophant, CFMatrix& M, |
---|
870 | CFArray& Pi, int j) |
---|
871 | { |
---|
872 | CanonicalForm E; |
---|
873 | CanonicalForm xToJ= power (F.mvar(), j); |
---|
874 | Variable x= F.mvar(); |
---|
875 | // compute the error |
---|
876 | if (j == 1) |
---|
877 | E= F[j]; |
---|
878 | else |
---|
879 | { |
---|
880 | if (degree (Pi [factors.length() - 2], x) > 0) |
---|
881 | E= F[j] - Pi [factors.length() - 2] [j]; |
---|
882 | else |
---|
883 | E= F[j]; |
---|
884 | } |
---|
885 | |
---|
886 | CFArray buf= CFArray (diophant.length()); |
---|
887 | bufFactors[0]= mod (factors.getFirst(), power (F.mvar(), j + 1)); |
---|
888 | int k= 0; |
---|
889 | CanonicalForm remainder; |
---|
890 | // actual lifting |
---|
891 | for (CFListIterator i= diophant; i.hasItem(); i++, k++) |
---|
892 | { |
---|
893 | if (degree (bufFactors[k], x) > 0) |
---|
894 | { |
---|
895 | if (k > 0) |
---|
896 | remainder= modNTL (E, bufFactors[k] [0]); |
---|
897 | else |
---|
898 | remainder= E; |
---|
899 | } |
---|
900 | else |
---|
901 | remainder= modNTL (E, bufFactors[k]); |
---|
902 | |
---|
903 | buf[k]= mulNTL (i.getItem(), remainder); |
---|
904 | if (degree (bufFactors[k], x) > 0) |
---|
905 | buf[k]= modNTL (buf[k], bufFactors[k] [0]); |
---|
906 | else |
---|
907 | buf[k]= modNTL (buf[k], bufFactors[k]); |
---|
908 | } |
---|
909 | for (k= 1; k < factors.length(); k++) |
---|
910 | bufFactors[k] += xToJ*buf[k]; |
---|
911 | |
---|
912 | // update Pi [0] |
---|
913 | int degBuf0= degree (bufFactors[0], x); |
---|
914 | int degBuf1= degree (bufFactors[1], x); |
---|
915 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
916 | M (j + 1, 1)= mulNTL (bufFactors[0] [j], bufFactors[1] [j]); |
---|
917 | CanonicalForm uIZeroJ; |
---|
918 | if (j == 1) |
---|
919 | { |
---|
920 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
921 | uIZeroJ= mulNTL ((bufFactors[0] [0] + bufFactors[0] [j]), |
---|
922 | (bufFactors[1] [0] + buf[1])) - M(1, 1) - M(j + 1, 1); |
---|
923 | else if (degBuf0 > 0) |
---|
924 | uIZeroJ= mulNTL (bufFactors[0] [j], bufFactors[1]); |
---|
925 | else if (degBuf1 > 0) |
---|
926 | uIZeroJ= mulNTL (bufFactors[0], buf[1]); |
---|
927 | else |
---|
928 | uIZeroJ= 0; |
---|
929 | Pi [0] += xToJ*uIZeroJ; |
---|
930 | } |
---|
931 | else |
---|
932 | { |
---|
933 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
934 | uIZeroJ= mulNTL ((bufFactors[0] [0] + bufFactors[0] [j]), |
---|
935 | (bufFactors[1] [0] + buf[1])) - M(1, 1) - M(j + 1, 1); |
---|
936 | else if (degBuf0 > 0) |
---|
937 | uIZeroJ= mulNTL (bufFactors[0] [j], bufFactors[1]); |
---|
938 | else if (degBuf1 > 0) |
---|
939 | uIZeroJ= mulNTL (bufFactors[0], buf[1]); |
---|
940 | else |
---|
941 | uIZeroJ= 0; |
---|
942 | Pi [0] += xToJ*uIZeroJ; |
---|
943 | } |
---|
944 | CFArray tmp= CFArray (factors.length() - 1); |
---|
945 | for (k= 0; k < factors.length() - 1; k++) |
---|
946 | tmp[k]= 0; |
---|
947 | CFIterator one, two; |
---|
948 | one= bufFactors [0]; |
---|
949 | two= bufFactors [1]; |
---|
950 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
951 | { |
---|
952 | for (k= 1; k <= (int) ceil (j/2.0); k++) |
---|
953 | { |
---|
954 | if (k != j - k + 1) |
---|
955 | { |
---|
956 | if (one.exp() == j - k + 1 && two.exp() == j - k + 1) |
---|
957 | { |
---|
958 | tmp[0] += mulNTL ((bufFactors[0] [k] + one.coeff()), (bufFactors[1] [k] + |
---|
959 | two.coeff())) - M (k + 1, 1) - M (j - k + 2, 1); |
---|
960 | one++; |
---|
961 | two++; |
---|
962 | } |
---|
963 | else if (one.exp() == j - k + 1) |
---|
964 | { |
---|
965 | tmp[0] += mulNTL ((bufFactors[0] [k] + one.coeff()), bufFactors[1] [k]) - |
---|
966 | M (k + 1, 1); |
---|
967 | one++; |
---|
968 | } |
---|
969 | else if (two.exp() == j - k + 1) |
---|
970 | { |
---|
971 | tmp[0] += mulNTL (bufFactors[0] [k], (bufFactors[1] [k] + two.coeff())) - |
---|
972 | M (k + 1, 1); |
---|
973 | two++; |
---|
974 | } |
---|
975 | } |
---|
976 | else |
---|
977 | { |
---|
978 | tmp[0] += M (k + 1, 1); |
---|
979 | } |
---|
980 | } |
---|
981 | } |
---|
982 | Pi [0] += tmp[0]*xToJ*F.mvar(); |
---|
983 | |
---|
984 | // update Pi [l] |
---|
985 | int degPi, degBuf; |
---|
986 | for (int l= 1; l < factors.length() - 1; l++) |
---|
987 | { |
---|
988 | degPi= degree (Pi [l - 1], x); |
---|
989 | degBuf= degree (bufFactors[l + 1], x); |
---|
990 | if (degPi > 0 && degBuf > 0) |
---|
991 | M (j + 1, l + 1)= mulNTL (Pi [l - 1] [j], bufFactors[l + 1] [j]); |
---|
992 | if (j == 1) |
---|
993 | { |
---|
994 | if (degPi > 0 && degBuf > 0) |
---|
995 | Pi [l] += xToJ*(mulNTL (Pi [l - 1] [0] + Pi [l - 1] [j], |
---|
996 | bufFactors[l + 1] [0] + buf[l + 1]) - M (j + 1, l +1) - |
---|
997 | M (1, l + 1)); |
---|
998 | else if (degPi > 0) |
---|
999 | Pi [l] += xToJ*(mulNTL (Pi [l - 1] [j], bufFactors[l + 1])); |
---|
1000 | else if (degBuf > 0) |
---|
1001 | Pi [l] += xToJ*(mulNTL (Pi [l - 1], buf[l + 1])); |
---|
1002 | } |
---|
1003 | else |
---|
1004 | { |
---|
1005 | if (degPi > 0 && degBuf > 0) |
---|
1006 | { |
---|
1007 | uIZeroJ= mulNTL (uIZeroJ, bufFactors [l + 1] [0]); |
---|
1008 | uIZeroJ += mulNTL (Pi [l - 1] [0], buf [l + 1]); |
---|
1009 | } |
---|
1010 | else if (degPi > 0) |
---|
1011 | uIZeroJ= mulNTL (uIZeroJ, bufFactors [l + 1]); |
---|
1012 | else if (degBuf > 0) |
---|
1013 | { |
---|
1014 | uIZeroJ= mulNTL (uIZeroJ, bufFactors [l + 1] [0]); |
---|
1015 | uIZeroJ += mulNTL (Pi [l - 1], buf[l + 1]); |
---|
1016 | } |
---|
1017 | Pi[l] += xToJ*uIZeroJ; |
---|
1018 | } |
---|
1019 | one= bufFactors [l + 1]; |
---|
1020 | two= Pi [l - 1]; |
---|
1021 | if (two.exp() == j + 1) |
---|
1022 | { |
---|
1023 | if (degBuf > 0 && degPi > 0) |
---|
1024 | { |
---|
1025 | tmp[l] += mulNTL (two.coeff(), bufFactors[l + 1][0]); |
---|
1026 | two++; |
---|
1027 | } |
---|
1028 | else if (degPi > 0) |
---|
1029 | { |
---|
1030 | tmp[l] += mulNTL (two.coeff(), bufFactors[l + 1]); |
---|
1031 | two++; |
---|
1032 | } |
---|
1033 | } |
---|
1034 | if (degBuf > 0 && degPi > 0) |
---|
1035 | { |
---|
1036 | for (k= 1; k <= (int) ceil (j/2.0); k++) |
---|
1037 | { |
---|
1038 | if (k != j - k + 1) |
---|
1039 | { |
---|
1040 | if (one.exp() == j - k + 1 && two.exp() == j - k + 1) |
---|
1041 | { |
---|
1042 | tmp[l] += mulNTL ((bufFactors[l + 1] [k] + one.coeff()), (Pi[l - 1] [k] + |
---|
1043 | two.coeff())) - M (k + 1, l + 1) - M (j - k + 2, l + 1); |
---|
1044 | one++; |
---|
1045 | two++; |
---|
1046 | } |
---|
1047 | else if (one.exp() == j - k + 1) |
---|
1048 | { |
---|
1049 | tmp[l] += mulNTL ((bufFactors[l + 1] [k] + one.coeff()), Pi[l - 1] [k]) - |
---|
1050 | M (k + 1, l + 1); |
---|
1051 | one++; |
---|
1052 | } |
---|
1053 | else if (two.exp() == j - k + 1) |
---|
1054 | { |
---|
1055 | tmp[l] += mulNTL (bufFactors[l + 1] [k], (Pi[l - 1] [k] + two.coeff())) - |
---|
1056 | M (k + 1, l + 1); |
---|
1057 | two++; |
---|
1058 | } |
---|
1059 | } |
---|
1060 | else |
---|
1061 | tmp[l] += M (k + 1, l + 1); |
---|
1062 | } |
---|
1063 | } |
---|
1064 | Pi[l] += tmp[l]*xToJ*F.mvar(); |
---|
1065 | } |
---|
1066 | return; |
---|
1067 | } |
---|
1068 | |
---|
1069 | void |
---|
1070 | henselLift12 (const CanonicalForm& F, CFList& factors, int l, CFArray& Pi, |
---|
1071 | CFList& diophant, CFMatrix& M) |
---|
1072 | { |
---|
1073 | sortList (factors, Variable (1)); |
---|
1074 | Pi= CFArray (factors.length() - 1); |
---|
1075 | CFListIterator j= factors; |
---|
1076 | diophant= diophantine (F[0], factors); |
---|
1077 | DEBOUTLN (cerr, "diophant= " << diophant); |
---|
1078 | j++; |
---|
1079 | Pi [0]= mulNTL (j.getItem(), mod (factors.getFirst(), F.mvar())); |
---|
1080 | M (1, 1)= Pi [0]; |
---|
1081 | int i= 1; |
---|
1082 | if (j.hasItem()) |
---|
1083 | j++; |
---|
1084 | for (j; j.hasItem(); j++, i++) |
---|
1085 | { |
---|
1086 | Pi [i]= mulNTL (Pi [i - 1], j.getItem()); |
---|
1087 | M (1, i + 1)= Pi [i]; |
---|
1088 | } |
---|
1089 | CFArray bufFactors= CFArray (factors.length()); |
---|
1090 | i= 0; |
---|
1091 | for (CFListIterator k= factors; k.hasItem(); i++, k++) |
---|
1092 | { |
---|
1093 | if (i == 0) |
---|
1094 | bufFactors[i]= mod (k.getItem(), F.mvar()); |
---|
1095 | else |
---|
1096 | bufFactors[i]= k.getItem(); |
---|
1097 | } |
---|
1098 | for (i= 1; i < l; i++) |
---|
1099 | henselStep12 (F, factors, bufFactors, diophant, M, Pi, i); |
---|
1100 | |
---|
1101 | CFListIterator k= factors; |
---|
1102 | for (i= 0; i < factors.length (); i++, k++) |
---|
1103 | k.getItem()= bufFactors[i]; |
---|
1104 | factors.removeFirst(); |
---|
1105 | return; |
---|
1106 | } |
---|
1107 | |
---|
1108 | void |
---|
1109 | henselLiftResume12 (const CanonicalForm& F, CFList& factors, int start, int |
---|
1110 | end, CFArray& Pi, const CFList& diophant, CFMatrix& M) |
---|
1111 | { |
---|
1112 | CFArray bufFactors= CFArray (factors.length()); |
---|
1113 | int i= 0; |
---|
1114 | CanonicalForm xToStart= power (F.mvar(), start); |
---|
1115 | for (CFListIterator k= factors; k.hasItem(); k++, i++) |
---|
1116 | { |
---|
1117 | if (i == 0) |
---|
1118 | bufFactors[i]= mod (k.getItem(), xToStart); |
---|
1119 | else |
---|
1120 | bufFactors[i]= k.getItem(); |
---|
1121 | } |
---|
1122 | for (i= start; i < end; i++) |
---|
1123 | henselStep12 (F, factors, bufFactors, diophant, M, Pi, i); |
---|
1124 | |
---|
1125 | CFListIterator k= factors; |
---|
1126 | for (i= 0; i < factors.length(); k++, i++) |
---|
1127 | k.getItem()= bufFactors [i]; |
---|
1128 | factors.removeFirst(); |
---|
1129 | return; |
---|
1130 | } |
---|
1131 | |
---|
1132 | static inline |
---|
1133 | CFList |
---|
1134 | biDiophantine (const CanonicalForm& F, const CFList& factors, const int d) |
---|
1135 | { |
---|
1136 | Variable y= F.mvar(); |
---|
1137 | CFList result; |
---|
1138 | if (y.level() == 1) |
---|
1139 | { |
---|
1140 | result= diophantine (F, factors); |
---|
1141 | return result; |
---|
1142 | } |
---|
1143 | else |
---|
1144 | { |
---|
1145 | CFList buf= factors; |
---|
1146 | for (CFListIterator i= buf; i.hasItem(); i++) |
---|
1147 | i.getItem()= mod (i.getItem(), y); |
---|
1148 | CanonicalForm A= mod (F, y); |
---|
1149 | int bufD= 1; |
---|
1150 | CFList recResult= biDiophantine (A, buf, bufD); |
---|
1151 | CanonicalForm e= 1; |
---|
1152 | CFList p; |
---|
1153 | CFArray bufFactors= CFArray (factors.length()); |
---|
1154 | CanonicalForm yToD= power (y, d); |
---|
1155 | int k= 0; |
---|
1156 | for (CFListIterator i= factors; i.hasItem(); i++, k++) |
---|
1157 | { |
---|
1158 | bufFactors [k]= i.getItem(); |
---|
1159 | } |
---|
1160 | CanonicalForm b; |
---|
1161 | for (k= 0; k < factors.length(); k++) //TODO compute b's faster |
---|
1162 | { |
---|
1163 | b= 1; |
---|
1164 | if (fdivides (bufFactors[k], F)) |
---|
1165 | b= F/bufFactors[k]; |
---|
1166 | else |
---|
1167 | { |
---|
1168 | for (int l= 0; l < factors.length(); l++) |
---|
1169 | { |
---|
1170 | if (l == k) |
---|
1171 | continue; |
---|
1172 | else |
---|
1173 | { |
---|
1174 | b= mulMod2 (b, bufFactors[l], yToD); |
---|
1175 | } |
---|
1176 | } |
---|
1177 | } |
---|
1178 | p.append (b); |
---|
1179 | } |
---|
1180 | |
---|
1181 | CFListIterator j= p; |
---|
1182 | for (CFListIterator i= recResult; i.hasItem(); i++, j++) |
---|
1183 | e -= i.getItem()*j.getItem(); |
---|
1184 | |
---|
1185 | if (e.isZero()) |
---|
1186 | return recResult; |
---|
1187 | CanonicalForm coeffE; |
---|
1188 | CFList s; |
---|
1189 | result= recResult; |
---|
1190 | CanonicalForm g; |
---|
1191 | for (int i= 1; i < d; i++) |
---|
1192 | { |
---|
1193 | if (degree (e, y) > 0) |
---|
1194 | coeffE= e[i]; |
---|
1195 | else |
---|
1196 | coeffE= 0; |
---|
1197 | if (!coeffE.isZero()) |
---|
1198 | { |
---|
1199 | CFListIterator k= result; |
---|
1200 | CFListIterator l= p; |
---|
1201 | int ii= 0; |
---|
1202 | j= recResult; |
---|
1203 | for (; j.hasItem(); j++, k++, l++, ii++) |
---|
1204 | { |
---|
1205 | g= coeffE*j.getItem(); |
---|
1206 | if (degree (bufFactors[ii], y) <= 0) |
---|
1207 | g= mod (g, bufFactors[ii]); |
---|
1208 | else |
---|
1209 | g= mod (g, bufFactors[ii][0]); |
---|
1210 | k.getItem() += g*power (y, i); |
---|
1211 | e -= mulMod2 (g*power(y, i), l.getItem(), yToD); |
---|
1212 | DEBOUTLN (cerr, "mod (e, power (y, i + 1))= " << |
---|
1213 | mod (e, power (y, i + 1))); |
---|
1214 | } |
---|
1215 | } |
---|
1216 | if (e.isZero()) |
---|
1217 | break; |
---|
1218 | } |
---|
1219 | |
---|
1220 | DEBOUTLN (cerr, "mod (e, y)= " << mod (e, y)); |
---|
1221 | |
---|
1222 | #ifdef DEBUGOUTPUT |
---|
1223 | CanonicalForm test= 0; |
---|
1224 | j= p; |
---|
1225 | for (CFListIterator i= result; i.hasItem(); i++, j++) |
---|
1226 | test += mod (i.getItem()*j.getItem(), power (y, d)); |
---|
1227 | DEBOUTLN (cerr, "test= " << test); |
---|
1228 | #endif |
---|
1229 | return result; |
---|
1230 | } |
---|
1231 | } |
---|
1232 | |
---|
1233 | static inline |
---|
1234 | CFList |
---|
1235 | multiRecDiophantine (const CanonicalForm& F, const CFList& factors, |
---|
1236 | const CFList& recResult, const CFList& M, const int d) |
---|
1237 | { |
---|
1238 | Variable y= F.mvar(); |
---|
1239 | CFList result; |
---|
1240 | CFListIterator i; |
---|
1241 | CanonicalForm e= 1; |
---|
1242 | CFListIterator j= factors; |
---|
1243 | CFList p; |
---|
1244 | CFArray bufFactors= CFArray (factors.length()); |
---|
1245 | CanonicalForm yToD= power (y, d); |
---|
1246 | int k= 0; |
---|
1247 | for (CFListIterator i= factors; i.hasItem(); i++, k++) |
---|
1248 | bufFactors [k]= i.getItem(); |
---|
1249 | CanonicalForm b; |
---|
1250 | CFList buf= M; |
---|
1251 | buf.removeLast(); |
---|
1252 | buf.append (yToD); |
---|
1253 | for (k= 0; k < factors.length(); k++) //TODO compute b's faster |
---|
1254 | { |
---|
1255 | b= 1; |
---|
1256 | if (fdivides (bufFactors[k], F)) |
---|
1257 | b= F/bufFactors[k]; |
---|
1258 | else |
---|
1259 | { |
---|
1260 | for (int l= 0; l < factors.length(); l++) |
---|
1261 | { |
---|
1262 | if (l == k) |
---|
1263 | continue; |
---|
1264 | else |
---|
1265 | { |
---|
1266 | b= mulMod (b, bufFactors[l], buf); |
---|
1267 | } |
---|
1268 | } |
---|
1269 | } |
---|
1270 | p.append (b); |
---|
1271 | } |
---|
1272 | j= p; |
---|
1273 | for (CFListIterator i= recResult; i.hasItem(); i++, j++) |
---|
1274 | e -= mulMod (i.getItem(), j.getItem(), M); |
---|
1275 | |
---|
1276 | if (e.isZero()) |
---|
1277 | return recResult; |
---|
1278 | CanonicalForm coeffE; |
---|
1279 | CFList s; |
---|
1280 | result= recResult; |
---|
1281 | CanonicalForm g; |
---|
1282 | for (int i= 1; i < d; i++) |
---|
1283 | { |
---|
1284 | if (degree (e, y) > 0) |
---|
1285 | coeffE= e[i]; |
---|
1286 | else |
---|
1287 | coeffE= 0; |
---|
1288 | if (!coeffE.isZero()) |
---|
1289 | { |
---|
1290 | CFListIterator k= result; |
---|
1291 | CFListIterator l= p; |
---|
1292 | j= recResult; |
---|
1293 | int ii= 0; |
---|
1294 | CanonicalForm dummy; |
---|
1295 | for (; j.hasItem(); j++, k++, l++, ii++) |
---|
1296 | { |
---|
1297 | g= mulMod (coeffE, j.getItem(), M); |
---|
1298 | if (degree (bufFactors[ii], y) <= 0) |
---|
1299 | divrem (g, mod (bufFactors[ii], Variable (y.level() - 1)), dummy, |
---|
1300 | g, M); |
---|
1301 | else |
---|
1302 | divrem (g, bufFactors[ii][0], dummy, g, M); |
---|
1303 | k.getItem() += g*power (y, i); |
---|
1304 | e -= mulMod (g*power (y, i), l.getItem(), M); |
---|
1305 | } |
---|
1306 | } |
---|
1307 | |
---|
1308 | if (e.isZero()) |
---|
1309 | break; |
---|
1310 | } |
---|
1311 | |
---|
1312 | #ifdef DEBUGOUTPUT |
---|
1313 | CanonicalForm test= 0; |
---|
1314 | j= p; |
---|
1315 | for (CFListIterator i= result; i.hasItem(); i++, j++) |
---|
1316 | test += mod (i.getItem()*j.getItem(), power (y, d)); |
---|
1317 | DEBOUTLN (cerr, "test= " << test); |
---|
1318 | #endif |
---|
1319 | return result; |
---|
1320 | } |
---|
1321 | |
---|
1322 | static inline |
---|
1323 | void |
---|
1324 | henselStep (const CanonicalForm& F, const CFList& factors, CFArray& bufFactors, |
---|
1325 | const CFList& diophant, CFMatrix& M, CFArray& Pi, int j, |
---|
1326 | const CFList& MOD) |
---|
1327 | { |
---|
1328 | CanonicalForm E; |
---|
1329 | CanonicalForm xToJ= power (F.mvar(), j); |
---|
1330 | Variable x= F.mvar(); |
---|
1331 | // compute the error |
---|
1332 | if (j == 1) |
---|
1333 | { |
---|
1334 | E= F[j]; |
---|
1335 | #ifdef DEBUGOUTPUT |
---|
1336 | CanonicalForm test= 1; |
---|
1337 | for (int i= 0; i < factors.length(); i++) |
---|
1338 | { |
---|
1339 | if (i == 0) |
---|
1340 | test= mulMod (test, mod (bufFactors [i], xToJ), MOD); |
---|
1341 | else |
---|
1342 | test= mulMod (test, bufFactors[i], MOD); |
---|
1343 | } |
---|
1344 | CanonicalForm test2= mod (F-test, xToJ); |
---|
1345 | |
---|
1346 | test2= mod (test2, MOD); |
---|
1347 | DEBOUTLN (cerr, "test= " << test2); |
---|
1348 | #endif |
---|
1349 | } |
---|
1350 | else |
---|
1351 | { |
---|
1352 | #ifdef DEBUGOUTPUT |
---|
1353 | CanonicalForm test= 1; |
---|
1354 | for (int i= 0; i < factors.length(); i++) |
---|
1355 | { |
---|
1356 | if (i == 0) |
---|
1357 | test *= mod (bufFactors [i], power (x, j)); |
---|
1358 | else |
---|
1359 | test *= bufFactors[i]; |
---|
1360 | } |
---|
1361 | test= mod (test, power (x, j)); |
---|
1362 | test= mod (test, MOD); |
---|
1363 | CanonicalForm test2= mod (F, power (x, j - 1)) - mod (test, power (x, j-1)); |
---|
1364 | DEBOUTLN (cerr, "test= " << test2); |
---|
1365 | #endif |
---|
1366 | |
---|
1367 | if (degree (Pi [factors.length() - 2], x) > 0) |
---|
1368 | E= F[j] - Pi [factors.length() - 2] [j]; |
---|
1369 | else |
---|
1370 | E= F[j]; |
---|
1371 | } |
---|
1372 | |
---|
1373 | CFArray buf= CFArray (diophant.length()); |
---|
1374 | bufFactors[0]= mod (factors.getFirst(), power (F.mvar(), j + 1)); |
---|
1375 | int k= 0; |
---|
1376 | // actual lifting |
---|
1377 | CanonicalForm dummy, rest1; |
---|
1378 | for (CFListIterator i= diophant; i.hasItem(); i++, k++) |
---|
1379 | { |
---|
1380 | if (degree (bufFactors[k], x) > 0) |
---|
1381 | { |
---|
1382 | if (k > 0) |
---|
1383 | divrem (E, bufFactors[k] [0], dummy, rest1, MOD); |
---|
1384 | else |
---|
1385 | rest1= E; |
---|
1386 | } |
---|
1387 | else |
---|
1388 | divrem (E, bufFactors[k], dummy, rest1, MOD); |
---|
1389 | |
---|
1390 | buf[k]= mulMod (i.getItem(), rest1, MOD); |
---|
1391 | |
---|
1392 | if (degree (bufFactors[k], x) > 0) |
---|
1393 | divrem (buf[k], bufFactors[k] [0], dummy, buf[k], MOD); |
---|
1394 | else |
---|
1395 | divrem (buf[k], bufFactors[k], dummy, buf[k], MOD); |
---|
1396 | } |
---|
1397 | for (k= 1; k < factors.length(); k++) |
---|
1398 | bufFactors[k] += xToJ*buf[k]; |
---|
1399 | |
---|
1400 | // update Pi [0] |
---|
1401 | int degBuf0= degree (bufFactors[0], x); |
---|
1402 | int degBuf1= degree (bufFactors[1], x); |
---|
1403 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
1404 | M (j + 1, 1)= mulMod (bufFactors[0] [j], bufFactors[1] [j], MOD); |
---|
1405 | CanonicalForm uIZeroJ; |
---|
1406 | if (j == 1) |
---|
1407 | { |
---|
1408 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
1409 | uIZeroJ= mulMod ((bufFactors[0] [0] + bufFactors[0] [j]), |
---|
1410 | (bufFactors[1] [0] + buf[1]), MOD) - M(1, 1) - M(j + 1, 1); |
---|
1411 | else if (degBuf0 > 0) |
---|
1412 | uIZeroJ= mulMod (bufFactors[0] [j], bufFactors[1], MOD); |
---|
1413 | else if (degBuf1 > 0) |
---|
1414 | uIZeroJ= mulMod (bufFactors[0], buf[1], MOD); |
---|
1415 | else |
---|
1416 | uIZeroJ= 0; |
---|
1417 | Pi [0] += xToJ*uIZeroJ; |
---|
1418 | } |
---|
1419 | else |
---|
1420 | { |
---|
1421 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
1422 | uIZeroJ= mulMod ((bufFactors[0] [0] + bufFactors[0] [j]), |
---|
1423 | (bufFactors[1] [0] + buf[1]), MOD) - M(1, 1) - M(j + 1, 1); |
---|
1424 | else if (degBuf0 > 0) |
---|
1425 | uIZeroJ= mulMod (bufFactors[0] [j], bufFactors[1], MOD); |
---|
1426 | else if (degBuf1 > 0) |
---|
1427 | uIZeroJ= mulMod (bufFactors[0], buf[1], MOD); |
---|
1428 | else |
---|
1429 | uIZeroJ= 0; |
---|
1430 | Pi [0] += xToJ*uIZeroJ; |
---|
1431 | } |
---|
1432 | |
---|
1433 | CFArray tmp= CFArray (factors.length() - 1); |
---|
1434 | for (k= 0; k < factors.length() - 1; k++) |
---|
1435 | tmp[k]= 0; |
---|
1436 | CFIterator one, two; |
---|
1437 | one= bufFactors [0]; |
---|
1438 | two= bufFactors [1]; |
---|
1439 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
1440 | { |
---|
1441 | for (k= 1; k <= (int) ceil (j/2.0); k++) |
---|
1442 | { |
---|
1443 | if (k != j - k + 1) |
---|
1444 | { |
---|
1445 | if (one.exp() == j - k + 1 && two.exp() == j - k + 1) |
---|
1446 | { |
---|
1447 | tmp[0] += mulMod ((bufFactors[0] [k] + one.coeff()), |
---|
1448 | (bufFactors[1] [k] + two.coeff()), MOD) - M (k + 1, 1) - |
---|
1449 | M (j - k + 2, 1); |
---|
1450 | one++; |
---|
1451 | two++; |
---|
1452 | } |
---|
1453 | else if (one.exp() == j - k + 1) |
---|
1454 | { |
---|
1455 | tmp[0] += mulMod ((bufFactors[0] [k] + one.coeff()), |
---|
1456 | bufFactors[1] [k], MOD) - M (k + 1, 1); |
---|
1457 | one++; |
---|
1458 | } |
---|
1459 | else if (two.exp() == j - k + 1) |
---|
1460 | { |
---|
1461 | tmp[0] += mulMod (bufFactors[0] [k], (bufFactors[1] [k] + |
---|
1462 | two.coeff()), MOD) - M (k + 1, 1); |
---|
1463 | two++; |
---|
1464 | } |
---|
1465 | } |
---|
1466 | else |
---|
1467 | { |
---|
1468 | tmp[0] += M (k + 1, 1); |
---|
1469 | } |
---|
1470 | } |
---|
1471 | } |
---|
1472 | Pi [0] += tmp[0]*xToJ*F.mvar(); |
---|
1473 | |
---|
1474 | // update Pi [l] |
---|
1475 | int degPi, degBuf; |
---|
1476 | for (int l= 1; l < factors.length() - 1; l++) |
---|
1477 | { |
---|
1478 | degPi= degree (Pi [l - 1], x); |
---|
1479 | degBuf= degree (bufFactors[l + 1], x); |
---|
1480 | if (degPi > 0 && degBuf > 0) |
---|
1481 | M (j + 1, l + 1)= mulMod (Pi [l - 1] [j], bufFactors[l + 1] [j], MOD); |
---|
1482 | if (j == 1) |
---|
1483 | { |
---|
1484 | if (degPi > 0 && degBuf > 0) |
---|
1485 | Pi [l] += xToJ*(mulMod ((Pi [l - 1] [0] + Pi [l - 1] [j]), |
---|
1486 | (bufFactors[l + 1] [0] + buf[l + 1]), MOD) - M (j + 1, l +1)- |
---|
1487 | M (1, l + 1)); |
---|
1488 | else if (degPi > 0) |
---|
1489 | Pi [l] += xToJ*(mulMod (Pi [l - 1] [j], bufFactors[l + 1], MOD)); |
---|
1490 | else if (degBuf > 0) |
---|
1491 | Pi [l] += xToJ*(mulMod (Pi [l - 1], buf[l + 1], MOD)); |
---|
1492 | } |
---|
1493 | else |
---|
1494 | { |
---|
1495 | if (degPi > 0 && degBuf > 0) |
---|
1496 | { |
---|
1497 | uIZeroJ= mulMod (uIZeroJ, bufFactors [l + 1] [0], MOD); |
---|
1498 | uIZeroJ += mulMod (Pi [l - 1] [0], buf [l + 1], MOD); |
---|
1499 | } |
---|
1500 | else if (degPi > 0) |
---|
1501 | uIZeroJ= mulMod (uIZeroJ, bufFactors [l + 1], MOD); |
---|
1502 | else if (degBuf > 0) |
---|
1503 | { |
---|
1504 | uIZeroJ= mulMod (uIZeroJ, bufFactors [l + 1] [0], MOD); |
---|
1505 | uIZeroJ += mulMod (Pi [l - 1], buf[l + 1], MOD); |
---|
1506 | } |
---|
1507 | Pi[l] += xToJ*uIZeroJ; |
---|
1508 | } |
---|
1509 | one= bufFactors [l + 1]; |
---|
1510 | two= Pi [l - 1]; |
---|
1511 | if (two.exp() == j + 1) |
---|
1512 | { |
---|
1513 | if (degBuf > 0 && degPi > 0) |
---|
1514 | { |
---|
1515 | tmp[l] += mulMod (two.coeff(), bufFactors[l + 1][0], MOD); |
---|
1516 | two++; |
---|
1517 | } |
---|
1518 | else if (degPi > 0) |
---|
1519 | { |
---|
1520 | tmp[l] += mulMod (two.coeff(), bufFactors[l + 1], MOD); |
---|
1521 | two++; |
---|
1522 | } |
---|
1523 | } |
---|
1524 | if (degBuf > 0 && degPi > 0) |
---|
1525 | { |
---|
1526 | for (k= 1; k <= (int) ceil (j/2.0); k++) |
---|
1527 | { |
---|
1528 | if (k != j - k + 1) |
---|
1529 | { |
---|
1530 | if (one.exp() == j - k + 1 && two.exp() == j - k + 1) |
---|
1531 | { |
---|
1532 | tmp[l] += mulMod ((bufFactors[l + 1] [k] + one.coeff()), |
---|
1533 | (Pi[l - 1] [k] + two.coeff()), MOD) - M (k + 1, l + 1) - |
---|
1534 | M (j - k + 2, l + 1); |
---|
1535 | one++; |
---|
1536 | two++; |
---|
1537 | } |
---|
1538 | else if (one.exp() == j - k + 1) |
---|
1539 | { |
---|
1540 | tmp[l] += mulMod ((bufFactors[l + 1] [k] + one.coeff()), |
---|
1541 | Pi[l - 1] [k], MOD) - M (k + 1, l + 1); |
---|
1542 | one++; |
---|
1543 | } |
---|
1544 | else if (two.exp() == j - k + 1) |
---|
1545 | { |
---|
1546 | tmp[l] += mulMod (bufFactors[l + 1] [k], |
---|
1547 | (Pi[l - 1] [k] + two.coeff()), MOD) - M (k + 1, l + 1); |
---|
1548 | two++; |
---|
1549 | } |
---|
1550 | } |
---|
1551 | else |
---|
1552 | tmp[l] += M (k + 1, l + 1); |
---|
1553 | } |
---|
1554 | } |
---|
1555 | Pi[l] += tmp[l]*xToJ*F.mvar(); |
---|
1556 | } |
---|
1557 | |
---|
1558 | return; |
---|
1559 | } |
---|
1560 | |
---|
1561 | CFList |
---|
1562 | henselLift23 (const CFList& eval, const CFList& factors, const int* l, CFList& |
---|
1563 | diophant, CFArray& Pi, CFMatrix& M) |
---|
1564 | { |
---|
1565 | CFList buf= factors; |
---|
1566 | int k= 0; |
---|
1567 | int liftBound; |
---|
1568 | int liftBoundBivar= l[k]; |
---|
1569 | diophant= biDiophantine (eval.getFirst(), buf, liftBoundBivar); |
---|
1570 | CFList MOD; |
---|
1571 | MOD.append (power (Variable (2), liftBoundBivar)); |
---|
1572 | CFArray bufFactors= CFArray (factors.length()); |
---|
1573 | k= 0; |
---|
1574 | CFListIterator j= eval; |
---|
1575 | j++; |
---|
1576 | buf.removeFirst(); |
---|
1577 | buf.insert (LC (j.getItem(), 1)); |
---|
1578 | for (CFListIterator i= buf; i.hasItem(); i++, k++) |
---|
1579 | bufFactors[k]= i.getItem(); |
---|
1580 | Pi= CFArray (factors.length() - 1); |
---|
1581 | CFListIterator i= buf; |
---|
1582 | i++; |
---|
1583 | Variable y= j.getItem().mvar(); |
---|
1584 | Pi [0]= mulMod (i.getItem(), mod (buf.getFirst(), y), MOD); |
---|
1585 | M (1, 1)= Pi [0]; |
---|
1586 | k= 1; |
---|
1587 | if (i.hasItem()) |
---|
1588 | i++; |
---|
1589 | for (i; i.hasItem(); i++, k++) |
---|
1590 | { |
---|
1591 | Pi [k]= mulMod (Pi [k - 1], i.getItem(), MOD); |
---|
1592 | M (1, k + 1)= Pi [k]; |
---|
1593 | } |
---|
1594 | |
---|
1595 | for (int d= 1; d < l[1]; d++) |
---|
1596 | henselStep (j.getItem(), buf, bufFactors, diophant, M, Pi, d, MOD); |
---|
1597 | CFList result; |
---|
1598 | for (k= 1; k < factors.length(); k++) |
---|
1599 | result.append (bufFactors[k]); |
---|
1600 | return result; |
---|
1601 | } |
---|
1602 | |
---|
1603 | void |
---|
1604 | henselLiftResume (const CanonicalForm& F, CFList& factors, int start, int end, |
---|
1605 | CFArray& Pi, const CFList& diophant, CFMatrix& M, |
---|
1606 | const CFList& MOD) |
---|
1607 | { |
---|
1608 | CFArray bufFactors= CFArray (factors.length()); |
---|
1609 | int i= 0; |
---|
1610 | CanonicalForm xToStart= power (F.mvar(), start); |
---|
1611 | for (CFListIterator k= factors; k.hasItem(); k++, i++) |
---|
1612 | { |
---|
1613 | if (i == 0) |
---|
1614 | bufFactors[i]= mod (k.getItem(), xToStart); |
---|
1615 | else |
---|
1616 | bufFactors[i]= k.getItem(); |
---|
1617 | } |
---|
1618 | for (i= start; i < end; i++) |
---|
1619 | henselStep (F, factors, bufFactors, diophant, M, Pi, i, MOD); |
---|
1620 | |
---|
1621 | CFListIterator k= factors; |
---|
1622 | for (i= 0; i < factors.length(); k++, i++) |
---|
1623 | k.getItem()= bufFactors [i]; |
---|
1624 | factors.removeFirst(); |
---|
1625 | return; |
---|
1626 | } |
---|
1627 | |
---|
1628 | CFList |
---|
1629 | henselLift (const CFList& F, const CFList& factors, const CFList& MOD, CFList& |
---|
1630 | diophant, CFArray& Pi, CFMatrix& M, const int lOld, const int |
---|
1631 | lNew) |
---|
1632 | { |
---|
1633 | diophant= multiRecDiophantine (F.getFirst(), factors, diophant, MOD, lOld); |
---|
1634 | int k= 0; |
---|
1635 | CFArray bufFactors= CFArray (factors.length()); |
---|
1636 | for (CFListIterator i= factors; i.hasItem(); i++, k++) |
---|
1637 | { |
---|
1638 | if (k == 0) |
---|
1639 | bufFactors[k]= LC (F.getLast(), 1); |
---|
1640 | else |
---|
1641 | bufFactors[k]= i.getItem(); |
---|
1642 | } |
---|
1643 | CFList buf= factors; |
---|
1644 | buf.removeFirst(); |
---|
1645 | buf.insert (LC (F.getLast(), 1)); |
---|
1646 | CFListIterator i= buf; |
---|
1647 | i++; |
---|
1648 | Variable y= F.getLast().mvar(); |
---|
1649 | Variable x= F.getFirst().mvar(); |
---|
1650 | CanonicalForm xToLOld= power (x, lOld); |
---|
1651 | Pi [0]= mod (Pi[0], xToLOld); |
---|
1652 | M (1, 1)= Pi [0]; |
---|
1653 | k= 1; |
---|
1654 | if (i.hasItem()) |
---|
1655 | i++; |
---|
1656 | for (i; i.hasItem(); i++, k++) |
---|
1657 | { |
---|
1658 | Pi [k]= mod (Pi [k], xToLOld); |
---|
1659 | M (1, k + 1)= Pi [k]; |
---|
1660 | } |
---|
1661 | |
---|
1662 | for (int d= 1; d < lNew; d++) |
---|
1663 | henselStep (F.getLast(), buf, bufFactors, diophant, M, Pi, d, MOD); |
---|
1664 | CFList result; |
---|
1665 | for (k= 1; k < factors.length(); k++) |
---|
1666 | result.append (bufFactors[k]); |
---|
1667 | return result; |
---|
1668 | } |
---|
1669 | |
---|
1670 | CFList |
---|
1671 | henselLift (const CFList& eval, const CFList& factors, const int* l, const int |
---|
1672 | lLength) |
---|
1673 | { |
---|
1674 | CFList diophant; |
---|
1675 | CFList buf= factors; |
---|
1676 | buf.insert (LC (eval.getFirst(), 1)); |
---|
1677 | sortList (buf, Variable (1)); |
---|
1678 | CFArray Pi; |
---|
1679 | CFMatrix M= CFMatrix (l[1], factors.length()); |
---|
1680 | CFList result= henselLift23 (eval, buf, l, diophant, Pi, M); |
---|
1681 | if (eval.length() == 2) |
---|
1682 | return result; |
---|
1683 | CFList MOD; |
---|
1684 | for (int i= 0; i < 2; i++) |
---|
1685 | MOD.append (power (Variable (i + 2), l[i])); |
---|
1686 | CFListIterator j= eval; |
---|
1687 | j++; |
---|
1688 | CFList bufEval; |
---|
1689 | bufEval.append (j.getItem()); |
---|
1690 | j++; |
---|
1691 | |
---|
1692 | for (int i= 2; i < lLength && j.hasItem(); i++, j++) |
---|
1693 | { |
---|
1694 | result.insert (LC (bufEval.getFirst(), 1)); |
---|
1695 | bufEval.append (j.getItem()); |
---|
1696 | M= CFMatrix (l[i], factors.length()); |
---|
1697 | result= henselLift (bufEval, result, MOD, diophant, Pi, M, l[i - 1], l[i]); |
---|
1698 | MOD.append (power (Variable (i + 2), l[i])); |
---|
1699 | bufEval.removeFirst(); |
---|
1700 | } |
---|
1701 | return result; |
---|
1702 | } |
---|
1703 | |
---|
1704 | void |
---|
1705 | henselStep122 (const CanonicalForm& F, const CFList& factors, |
---|
1706 | CFArray& bufFactors, const CFList& diophant, CFMatrix& M, |
---|
1707 | CFArray& Pi, int j, const CFArray& LCs) |
---|
1708 | { |
---|
1709 | Variable x= F.mvar(); |
---|
1710 | CanonicalForm xToJ= power (x, j); |
---|
1711 | |
---|
1712 | CanonicalForm E; |
---|
1713 | // compute the error |
---|
1714 | if (degree (Pi [factors.length() - 2], x) > 0) |
---|
1715 | E= F[j] - Pi [factors.length() - 2] [j]; |
---|
1716 | else |
---|
1717 | E= F[j]; |
---|
1718 | |
---|
1719 | CFArray buf= CFArray (diophant.length()); |
---|
1720 | |
---|
1721 | int k= 0; |
---|
1722 | CanonicalForm remainder; |
---|
1723 | // actual lifting |
---|
1724 | for (CFListIterator i= diophant; i.hasItem(); i++, k++) |
---|
1725 | { |
---|
1726 | if (degree (bufFactors[k], x) > 0) |
---|
1727 | remainder= modNTL (E, bufFactors[k] [0]); |
---|
1728 | else |
---|
1729 | remainder= modNTL (E, bufFactors[k]); |
---|
1730 | buf[k]= mulNTL (i.getItem(), remainder); |
---|
1731 | if (degree (bufFactors[k], x) > 0) |
---|
1732 | buf[k]= modNTL (buf[k], bufFactors[k] [0]); |
---|
1733 | else |
---|
1734 | buf[k]= modNTL (buf[k], bufFactors[k]); |
---|
1735 | } |
---|
1736 | |
---|
1737 | for (k= 0; k < factors.length(); k++) |
---|
1738 | bufFactors[k] += xToJ*buf[k]; |
---|
1739 | |
---|
1740 | // update Pi [0] |
---|
1741 | int degBuf0= degree (bufFactors[0], x); |
---|
1742 | int degBuf1= degree (bufFactors[1], x); |
---|
1743 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
1744 | { |
---|
1745 | M (j + 1, 1)= mulNTL (bufFactors[0] [j], bufFactors[1] [j]); |
---|
1746 | if (j + 2 <= M.rows()) |
---|
1747 | M (j + 2, 1)= mulNTL (bufFactors[0] [j + 1], bufFactors[1] [j + 1]); |
---|
1748 | } |
---|
1749 | CanonicalForm uIZeroJ; |
---|
1750 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
1751 | uIZeroJ= mulNTL(bufFactors[0][0],buf[1])+mulNTL (bufFactors[1][0], buf[0]); |
---|
1752 | else if (degBuf0 > 0) |
---|
1753 | uIZeroJ= mulNTL (buf[0], bufFactors[1]); |
---|
1754 | else if (degBuf1 > 0) |
---|
1755 | uIZeroJ= mulNTL (bufFactors[0], buf [1]); |
---|
1756 | else |
---|
1757 | uIZeroJ= 0; |
---|
1758 | Pi [0] += xToJ*uIZeroJ; |
---|
1759 | |
---|
1760 | CFArray tmp= CFArray (factors.length() - 1); |
---|
1761 | for (k= 0; k < factors.length() - 1; k++) |
---|
1762 | tmp[k]= 0; |
---|
1763 | CFIterator one, two; |
---|
1764 | one= bufFactors [0]; |
---|
1765 | two= bufFactors [1]; |
---|
1766 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
1767 | { |
---|
1768 | while (one.hasTerms() && one.exp() > j) one++; |
---|
1769 | while (two.hasTerms() && two.exp() > j) two++; |
---|
1770 | for (k= 1; k <= (int) ceil (j/2.0); k++) |
---|
1771 | { |
---|
1772 | if (k != j - k + 1) |
---|
1773 | { |
---|
1774 | if (one.exp() == j - k + 1 && two.exp() == j - k + 1) |
---|
1775 | { |
---|
1776 | tmp[0] += mulNTL ((bufFactors[0][k]+one.coeff()),(bufFactors[1][k] + |
---|
1777 | two.coeff())) - M (k + 1, 1) - M (j - k + 2, 1); |
---|
1778 | one++; |
---|
1779 | two++; |
---|
1780 | } |
---|
1781 | else if (one.exp() == j - k + 1) |
---|
1782 | { |
---|
1783 | tmp[0] += mulNTL ((bufFactors[0][k]+one.coeff()), bufFactors[1] [k]) - |
---|
1784 | M (k + 1, 1); |
---|
1785 | one++; |
---|
1786 | } |
---|
1787 | else if (two.exp() == j - k + 1) |
---|
1788 | { |
---|
1789 | tmp[0] += mulNTL (bufFactors[0][k],(bufFactors[1][k] + two.coeff())) - |
---|
1790 | M (k + 1, 1); |
---|
1791 | two++; |
---|
1792 | } |
---|
1793 | } |
---|
1794 | else |
---|
1795 | tmp[0] += M (k + 1, 1); |
---|
1796 | } |
---|
1797 | } |
---|
1798 | |
---|
1799 | if (degBuf0 >= j + 1 && degBuf1 >= j + 1) |
---|
1800 | { |
---|
1801 | if (j + 2 <= M.rows()) |
---|
1802 | tmp [0] += mulNTL ((bufFactors [0] [j + 1]+ bufFactors [0] [0]), |
---|
1803 | (bufFactors [1] [j + 1] + bufFactors [1] [0])) |
---|
1804 | - M(1,1) - M (j + 2,1); |
---|
1805 | } |
---|
1806 | else if (degBuf0 >= j + 1) |
---|
1807 | { |
---|
1808 | if (degBuf1 > 0) |
---|
1809 | tmp[0] += mulNTL (bufFactors [0] [j+1], bufFactors [1] [0]); |
---|
1810 | else |
---|
1811 | tmp[0] += mulNTL (bufFactors [0] [j+1], bufFactors [1]); |
---|
1812 | } |
---|
1813 | else if (degBuf1 >= j + 1) |
---|
1814 | { |
---|
1815 | if (degBuf0 > 0) |
---|
1816 | tmp[0] += mulNTL (bufFactors [0] [0], bufFactors [1] [j + 1]); |
---|
1817 | else |
---|
1818 | tmp[0] += mulNTL (bufFactors [0], bufFactors [1] [j + 1]); |
---|
1819 | } |
---|
1820 | |
---|
1821 | Pi [0] += tmp[0]*xToJ*F.mvar(); |
---|
1822 | |
---|
1823 | /*// update Pi [l] |
---|
1824 | int degPi, degBuf; |
---|
1825 | for (int l= 1; l < factors.length() - 1; l++) |
---|
1826 | { |
---|
1827 | degPi= degree (Pi [l - 1], x); |
---|
1828 | degBuf= degree (bufFactors[l + 1], x); |
---|
1829 | if (degPi > 0 && degBuf > 0) |
---|
1830 | M (j + 1, l + 1)= mulNTL (Pi [l - 1] [j], bufFactors[l + 1] [j]); |
---|
1831 | if (j == 1) |
---|
1832 | { |
---|
1833 | if (degPi > 0 && degBuf > 0) |
---|
1834 | Pi [l] += xToJ*(mulNTL (Pi [l - 1] [0] + Pi [l - 1] [j], |
---|
1835 | bufFactors[l + 1] [0] + buf[l + 1]) - M (j + 1, l +1) - |
---|
1836 | M (1, l + 1)); |
---|
1837 | else if (degPi > 0) |
---|
1838 | Pi [l] += xToJ*(mulNTL (Pi [l - 1] [j], bufFactors[l + 1])); |
---|
1839 | else if (degBuf > 0) |
---|
1840 | Pi [l] += xToJ*(mulNTL (Pi [l - 1], buf[l + 1])); |
---|
1841 | } |
---|
1842 | else |
---|
1843 | { |
---|
1844 | if (degPi > 0 && degBuf > 0) |
---|
1845 | { |
---|
1846 | uIZeroJ= mulNTL (uIZeroJ, bufFactors [l + 1] [0]); |
---|
1847 | uIZeroJ += mulNTL (Pi [l - 1] [0], buf [l + 1]); |
---|
1848 | } |
---|
1849 | else if (degPi > 0) |
---|
1850 | uIZeroJ= mulNTL (uIZeroJ, bufFactors [l + 1]); |
---|
1851 | else if (degBuf > 0) |
---|
1852 | { |
---|
1853 | uIZeroJ= mulNTL (uIZeroJ, bufFactors [l + 1] [0]); |
---|
1854 | uIZeroJ += mulNTL (Pi [l - 1], buf[l + 1]); |
---|
1855 | } |
---|
1856 | Pi[l] += xToJ*uIZeroJ; |
---|
1857 | } |
---|
1858 | one= bufFactors [l + 1]; |
---|
1859 | two= Pi [l - 1]; |
---|
1860 | if (two.exp() == j + 1) |
---|
1861 | { |
---|
1862 | if (degBuf > 0 && degPi > 0) |
---|
1863 | { |
---|
1864 | tmp[l] += mulNTL (two.coeff(), bufFactors[l + 1][0]); |
---|
1865 | two++; |
---|
1866 | } |
---|
1867 | else if (degPi > 0) |
---|
1868 | { |
---|
1869 | tmp[l] += mulNTL (two.coeff(), bufFactors[l + 1]); |
---|
1870 | two++; |
---|
1871 | } |
---|
1872 | } |
---|
1873 | if (degBuf > 0 && degPi > 0) |
---|
1874 | { |
---|
1875 | for (k= 1; k <= (int) ceil (j/2.0); k++) |
---|
1876 | { |
---|
1877 | if (k != j - k + 1) |
---|
1878 | { |
---|
1879 | if (one.exp() == j - k + 1 && two.exp() == j - k + 1) |
---|
1880 | { |
---|
1881 | tmp[l] += mulNTL ((bufFactors[l + 1][k]+one.coeff()),(Pi[l-1] [k] + |
---|
1882 | two.coeff())) - M (k + 1, l + 1) - M (j - k + 2, l + 1); |
---|
1883 | one++; |
---|
1884 | two++; |
---|
1885 | } |
---|
1886 | else if (one.exp() == j - k + 1) |
---|
1887 | { |
---|
1888 | tmp[l] += mulNTL ((bufFactors[l+1][k]+one.coeff()),Pi[l - 1] [k]) - |
---|
1889 | M (k + 1, l + 1); |
---|
1890 | one++; |
---|
1891 | } |
---|
1892 | else if (two.exp() == j - k + 1) |
---|
1893 | { |
---|
1894 | tmp[l] += mulNTL (bufFactors[l+1][k],(Pi[l-1] [k] + two.coeff())) - |
---|
1895 | M (k + 1, l + 1); |
---|
1896 | two++; |
---|
1897 | } |
---|
1898 | } |
---|
1899 | else |
---|
1900 | tmp[l] += M (k + 1, l + 1); |
---|
1901 | } |
---|
1902 | } |
---|
1903 | Pi[l] += tmp[l]*xToJ*F.mvar(); |
---|
1904 | }*/ |
---|
1905 | return; |
---|
1906 | } |
---|
1907 | |
---|
1908 | void |
---|
1909 | henselLift122 (const CanonicalForm& F, CFList& factors, int l, CFArray& Pi, |
---|
1910 | CFList& diophant, CFMatrix& M, const CFArray& LCs, bool sort) |
---|
1911 | { |
---|
1912 | if (sort) |
---|
1913 | sortList (factors, Variable (1)); |
---|
1914 | Pi= CFArray (factors.length() - 2); |
---|
1915 | CFList bufFactors2= factors; |
---|
1916 | bufFactors2.removeFirst(); |
---|
1917 | diophant.removeFirst(); |
---|
1918 | CFListIterator iter= diophant; |
---|
1919 | CanonicalForm s,t; |
---|
1920 | extgcd (bufFactors2.getFirst(), bufFactors2.getLast(), s, t); |
---|
1921 | diophant= CFList(); |
---|
1922 | diophant.append (t); |
---|
1923 | diophant.append (s); |
---|
1924 | DEBOUTLN (cerr, "diophant= " << diophant); |
---|
1925 | |
---|
1926 | CFArray bufFactors= CFArray (bufFactors2.length()); |
---|
1927 | int i= 0; |
---|
1928 | for (CFListIterator k= bufFactors2; k.hasItem(); i++, k++) |
---|
1929 | bufFactors[i]= replaceLc (k.getItem(), LCs [i]); |
---|
1930 | |
---|
1931 | Variable x= F.mvar(); |
---|
1932 | if (degree (bufFactors[0], x) > 0 && degree (bufFactors [1], x) > 0) |
---|
1933 | { |
---|
1934 | M (1, 1)= mulNTL (bufFactors [0] [0], bufFactors[1] [0]); |
---|
1935 | Pi [0]= M (1, 1) + (mulNTL (bufFactors [0] [1], bufFactors[1] [0]) + |
---|
1936 | mulNTL (bufFactors [0] [0], bufFactors [1] [1]))*x; |
---|
1937 | } |
---|
1938 | else if (degree (bufFactors[0], x) > 0) |
---|
1939 | { |
---|
1940 | M (1, 1)= mulNTL (bufFactors [0] [0], bufFactors[1]); |
---|
1941 | Pi [0]= M (1, 1) + |
---|
1942 | mulNTL (bufFactors [0] [1], bufFactors[1])*x; |
---|
1943 | } |
---|
1944 | else if (degree (bufFactors[1], x) > 0) |
---|
1945 | { |
---|
1946 | M (1, 1)= mulNTL (bufFactors [0], bufFactors[1] [0]); |
---|
1947 | Pi [0]= M (1, 1) + |
---|
1948 | mulNTL (bufFactors [0], bufFactors[1] [1])*x; |
---|
1949 | } |
---|
1950 | else |
---|
1951 | { |
---|
1952 | M (1, 1)= mulNTL (bufFactors [0], bufFactors[1]); |
---|
1953 | Pi [0]= M (1, 1); |
---|
1954 | } |
---|
1955 | |
---|
1956 | for (i= 1; i < l; i++) |
---|
1957 | henselStep122 (F, bufFactors2, bufFactors, diophant, M, Pi, i, LCs); |
---|
1958 | |
---|
1959 | factors= CFList(); |
---|
1960 | for (i= 0; i < bufFactors.size(); i++) |
---|
1961 | factors.append (bufFactors[i]); |
---|
1962 | return; |
---|
1963 | } |
---|
1964 | |
---|
1965 | /// solve \f$ E=sum_{i= 1}^{r}{\sigma_{i}prod_{j=1, j\neq i}^{r}{f_{i}}}\f$ |
---|
1966 | /// mod M, products contains \f$ prod_{j=1, j\neq i}^{r}{f_{i}}} \f$ |
---|
1967 | static inline |
---|
1968 | CFList |
---|
1969 | diophantine (const CFList& recResult, const CFList& factors, |
---|
1970 | const CFList& products, const CFList& M, const CanonicalForm& E) |
---|
1971 | { |
---|
1972 | if (M.isEmpty()) |
---|
1973 | { |
---|
1974 | CFList result; |
---|
1975 | CFListIterator j= factors; |
---|
1976 | CanonicalForm buf; |
---|
1977 | for (CFListIterator i= recResult; i.hasItem(); i++, j++) |
---|
1978 | { |
---|
1979 | ASSERT (E.isUnivariate() || E.inCoeffDomain(), |
---|
1980 | "constant or univariate poly expected"); |
---|
1981 | ASSERT (i.getItem().isUnivariate() || i.getItem().inCoeffDomain(), |
---|
1982 | "constant or univariate poly expected"); |
---|
1983 | ASSERT (j.getItem().isUnivariate() || j.getItem().inCoeffDomain(), |
---|
1984 | "constant or univariate poly expected"); |
---|
1985 | buf= mulNTL (E, i.getItem()); |
---|
1986 | result.append (modNTL (buf, j.getItem())); |
---|
1987 | } |
---|
1988 | return result; |
---|
1989 | } |
---|
1990 | Variable y= M.getLast().mvar(); |
---|
1991 | CFList bufFactors= factors; |
---|
1992 | for (CFListIterator i= bufFactors; i.hasItem(); i++) |
---|
1993 | i.getItem()= mod (i.getItem(), y); |
---|
1994 | CFList bufProducts= products; |
---|
1995 | for (CFListIterator i= bufProducts; i.hasItem(); i++) |
---|
1996 | i.getItem()= mod (i.getItem(), y); |
---|
1997 | CFList buf= M; |
---|
1998 | buf.removeLast(); |
---|
1999 | CanonicalForm bufE= mod (E, y); |
---|
2000 | CFList recDiophantine= diophantine (recResult, bufFactors, bufProducts, buf, |
---|
2001 | bufE); |
---|
2002 | |
---|
2003 | CanonicalForm e= E; |
---|
2004 | CFListIterator j= products; |
---|
2005 | for (CFListIterator i= recDiophantine; i.hasItem(); i++, j++) |
---|
2006 | e -= mulMod (i.getItem(), j.getItem(), M); |
---|
2007 | |
---|
2008 | CFList result= recDiophantine; |
---|
2009 | int d= degree (M.getLast()); |
---|
2010 | CanonicalForm coeffE; |
---|
2011 | for (int i= 1; i < d; i++) |
---|
2012 | { |
---|
2013 | if (degree (e, y) > 0) |
---|
2014 | coeffE= e[i]; |
---|
2015 | else |
---|
2016 | coeffE= 0; |
---|
2017 | if (!coeffE.isZero()) |
---|
2018 | { |
---|
2019 | CFListIterator k= result; |
---|
2020 | recDiophantine= diophantine (recResult, bufFactors, bufProducts, buf, |
---|
2021 | coeffE); |
---|
2022 | CFListIterator l= products; |
---|
2023 | for (j= recDiophantine; j.hasItem(); j++, k++, l++) |
---|
2024 | { |
---|
2025 | k.getItem() += j.getItem()*power (y, i); |
---|
2026 | e -= mulMod (j.getItem()*power (y, i), l.getItem(), M); |
---|
2027 | } |
---|
2028 | } |
---|
2029 | if (e.isZero()) |
---|
2030 | break; |
---|
2031 | } |
---|
2032 | return result; |
---|
2033 | } |
---|
2034 | |
---|
2035 | // non monic case |
---|
2036 | static inline |
---|
2037 | CFList |
---|
2038 | multiRecDiophantine2 (const CanonicalForm& F, const CFList& factors, |
---|
2039 | const CFList& recResult, const CFList& M, const int d) |
---|
2040 | { |
---|
2041 | Variable y= F.mvar(); |
---|
2042 | CFList result; |
---|
2043 | CFListIterator i; |
---|
2044 | CanonicalForm e= 1; |
---|
2045 | CFListIterator j= factors; |
---|
2046 | CFList p; |
---|
2047 | CFArray bufFactors= CFArray (factors.length()); |
---|
2048 | CanonicalForm yToD= power (y, d); |
---|
2049 | int k= 0; |
---|
2050 | for (CFListIterator i= factors; i.hasItem(); i++, k++) |
---|
2051 | bufFactors [k]= i.getItem(); |
---|
2052 | CanonicalForm b; |
---|
2053 | CFList buf= M; |
---|
2054 | buf.removeLast(); |
---|
2055 | buf.append (yToD); |
---|
2056 | for (k= 0; k < factors.length(); k++) //TODO compute b's faster |
---|
2057 | { |
---|
2058 | b= 1; |
---|
2059 | if (fdivides (bufFactors[k], F)) |
---|
2060 | b= F/bufFactors[k]; |
---|
2061 | else |
---|
2062 | { |
---|
2063 | for (int l= 0; l < factors.length(); l++) |
---|
2064 | { |
---|
2065 | if (l == k) |
---|
2066 | continue; |
---|
2067 | else |
---|
2068 | { |
---|
2069 | b= mulMod (b, bufFactors[l], buf); |
---|
2070 | } |
---|
2071 | } |
---|
2072 | } |
---|
2073 | p.append (b); |
---|
2074 | } |
---|
2075 | j= p; |
---|
2076 | for (CFListIterator i= recResult; i.hasItem(); i++, j++) |
---|
2077 | e -= mulMod (i.getItem(), j.getItem(), M); |
---|
2078 | if (e.isZero()) |
---|
2079 | return recResult; |
---|
2080 | CanonicalForm coeffE; |
---|
2081 | result= recResult; |
---|
2082 | CanonicalForm g; |
---|
2083 | buf.removeLast(); |
---|
2084 | for (int i= 1; i < d; i++) |
---|
2085 | { |
---|
2086 | if (degree (e, y) > 0) |
---|
2087 | coeffE= e[i]; |
---|
2088 | else |
---|
2089 | coeffE= 0; |
---|
2090 | if (!coeffE.isZero()) |
---|
2091 | { |
---|
2092 | CFListIterator k= result; |
---|
2093 | CFListIterator l= p; |
---|
2094 | j= recResult; |
---|
2095 | int ii= 0; |
---|
2096 | CanonicalForm dummy; |
---|
2097 | CFList recDiophantine; |
---|
2098 | CFList buf2, buf3; |
---|
2099 | buf2= factors; |
---|
2100 | buf3= p; |
---|
2101 | for (CFListIterator iii= buf2; iii.hasItem(); iii++) |
---|
2102 | iii.getItem()= mod (iii.getItem(), y); |
---|
2103 | for (CFListIterator iii= buf3; iii.hasItem(); iii++) |
---|
2104 | iii.getItem()= mod (iii.getItem(), y); |
---|
2105 | recDiophantine= diophantine (recResult, buf2, buf3, buf, coeffE); |
---|
2106 | CFListIterator iter= recDiophantine; |
---|
2107 | for (; j.hasItem(); j++, k++, l++, ii++, iter++) |
---|
2108 | { |
---|
2109 | k.getItem() += iter.getItem()*power (y, i); |
---|
2110 | e -= mulMod (iter.getItem()*power (y, i), l.getItem(), M); |
---|
2111 | } |
---|
2112 | } |
---|
2113 | if (e.isZero()) |
---|
2114 | break; |
---|
2115 | } |
---|
2116 | |
---|
2117 | #ifdef DEBUGOUTPUT |
---|
2118 | CanonicalForm test= 0; |
---|
2119 | j= p; |
---|
2120 | for (CFListIterator i= result; i.hasItem(); i++, j++) |
---|
2121 | test += mod (i.getItem()*j.getItem(), power (y, d)); |
---|
2122 | DEBOUTLN (cerr, "test= " << test); |
---|
2123 | #endif |
---|
2124 | return result; |
---|
2125 | } |
---|
2126 | |
---|
2127 | // so far only tested for two! factor Hensel lifting |
---|
2128 | static inline |
---|
2129 | void |
---|
2130 | henselStep2 (const CanonicalForm& F, const CFList& factors, CFArray& bufFactors, |
---|
2131 | const CFList& diophant, CFMatrix& M, CFArray& Pi, |
---|
2132 | const CFList& products, int j, const CFList& MOD) |
---|
2133 | { |
---|
2134 | CanonicalForm E; |
---|
2135 | CanonicalForm xToJ= power (F.mvar(), j); |
---|
2136 | Variable x= F.mvar(); |
---|
2137 | |
---|
2138 | // compute the error |
---|
2139 | #ifdef DEBUGOUTPUT |
---|
2140 | CanonicalForm test= 1; |
---|
2141 | for (int i= 0; i < factors.length(); i++) |
---|
2142 | { |
---|
2143 | if (i == 0) |
---|
2144 | test *= mod (bufFactors [i], power (x, j)); |
---|
2145 | else |
---|
2146 | test *= bufFactors[i]; |
---|
2147 | } |
---|
2148 | test= mod (test, power (x, j)); |
---|
2149 | test= mod (test, MOD); |
---|
2150 | CanonicalForm test2= mod (F, power (x, j - 1)) - mod (test, power (x, j-1)); |
---|
2151 | DEBOUTLN (cerr, "test= " << test2); |
---|
2152 | #endif |
---|
2153 | |
---|
2154 | if (degree (Pi [factors.length() - 2], x) > 0) |
---|
2155 | E= F[j] - Pi [factors.length() - 2] [j]; |
---|
2156 | else |
---|
2157 | E= F[j]; |
---|
2158 | |
---|
2159 | CFArray buf= CFArray (diophant.length()); |
---|
2160 | |
---|
2161 | // actual lifting |
---|
2162 | CFList diophantine2= diophantine (diophant, factors, products, MOD, E); |
---|
2163 | |
---|
2164 | int k= 0; |
---|
2165 | for (CFListIterator i= diophantine2; k < factors.length(); k++, i++) |
---|
2166 | { |
---|
2167 | buf[k]= i.getItem(); |
---|
2168 | bufFactors[k] += xToJ*i.getItem(); |
---|
2169 | } |
---|
2170 | |
---|
2171 | // update Pi [0] |
---|
2172 | int degBuf0= degree (bufFactors[0], x); |
---|
2173 | int degBuf1= degree (bufFactors[1], x); |
---|
2174 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
2175 | { |
---|
2176 | M (j + 1, 1)= mulMod (bufFactors[0] [j], bufFactors[1] [j], MOD); |
---|
2177 | if (j + 2 <= M.rows()) |
---|
2178 | M (j + 2, 1)= mulMod (bufFactors[0] [j + 1], bufFactors[1] [j + 1], MOD); |
---|
2179 | } |
---|
2180 | CanonicalForm uIZeroJ; |
---|
2181 | |
---|
2182 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
2183 | uIZeroJ= mulMod (bufFactors[0] [0], buf[1], MOD) + |
---|
2184 | mulMod (bufFactors[1] [0], buf[0], MOD); |
---|
2185 | else if (degBuf0 > 0) |
---|
2186 | uIZeroJ= mulMod (buf[0], bufFactors[1], MOD); |
---|
2187 | else if (degBuf1 > 0) |
---|
2188 | uIZeroJ= mulMod (bufFactors[0], buf[1], MOD); |
---|
2189 | else |
---|
2190 | uIZeroJ= 0; |
---|
2191 | Pi [0] += xToJ*uIZeroJ; |
---|
2192 | |
---|
2193 | CFArray tmp= CFArray (factors.length() - 1); |
---|
2194 | for (k= 0; k < factors.length() - 1; k++) |
---|
2195 | tmp[k]= 0; |
---|
2196 | CFIterator one, two; |
---|
2197 | one= bufFactors [0]; |
---|
2198 | two= bufFactors [1]; |
---|
2199 | if (degBuf0 > 0 && degBuf1 > 0) |
---|
2200 | { |
---|
2201 | while (one.hasTerms() && one.exp() > j) one++; |
---|
2202 | while (two.hasTerms() && two.exp() > j) two++; |
---|
2203 | for (k= 1; k <= (int) ceil (j/2.0); k++) |
---|
2204 | { |
---|
2205 | if (k != j - k + 1) |
---|
2206 | { |
---|
2207 | if (one.exp() == j - k + 1 && two.exp() == j - k + 1) |
---|
2208 | { |
---|
2209 | tmp[0] += mulMod ((bufFactors[0] [k] + one.coeff()), |
---|
2210 | (bufFactors[1] [k] + two.coeff()), MOD) - M (k + 1, 1) - |
---|
2211 | M (j - k + 2, 1); |
---|
2212 | one++; |
---|
2213 | two++; |
---|
2214 | } |
---|
2215 | else if (one.exp() == j - k + 1) |
---|
2216 | { |
---|
2217 | tmp[0] += mulMod ((bufFactors[0] [k] + one.coeff()), |
---|
2218 | bufFactors[1] [k], MOD) - M (k + 1, 1); |
---|
2219 | one++; |
---|
2220 | } |
---|
2221 | else if (two.exp() == j - k + 1) |
---|
2222 | { |
---|
2223 | tmp[0] += mulMod (bufFactors[0] [k], (bufFactors[1] [k] + |
---|
2224 | two.coeff()), MOD) - M (k + 1, 1); |
---|
2225 | two++; |
---|
2226 | } |
---|
2227 | } |
---|
2228 | else |
---|
2229 | { |
---|
2230 | tmp[0] += M (k + 1, 1); |
---|
2231 | } |
---|
2232 | } |
---|
2233 | } |
---|
2234 | |
---|
2235 | if (degBuf0 >= j + 1 && degBuf1 >= j + 1) |
---|
2236 | { |
---|
2237 | if (j + 2 <= M.rows()) |
---|
2238 | tmp [0] += mulMod ((bufFactors [0] [j + 1]+ bufFactors [0] [0]), |
---|
2239 | (bufFactors [1] [j + 1] + bufFactors [1] [0]), MOD) |
---|
2240 | - M(1,1) - M (j + 2,1); |
---|
2241 | } |
---|
2242 | else if (degBuf0 >= j + 1) |
---|
2243 | { |
---|
2244 | if (degBuf1 > 0) |
---|
2245 | tmp[0] += mulMod (bufFactors [0] [j+1], bufFactors [1] [0], MOD); |
---|
2246 | else |
---|
2247 | tmp[0] += mulMod (bufFactors [0] [j+1], bufFactors [1], MOD); |
---|
2248 | } |
---|
2249 | else if (degBuf1 >= j + 1) |
---|
2250 | { |
---|
2251 | if (degBuf0 > 0) |
---|
2252 | tmp[0] += mulMod (bufFactors [0] [0], bufFactors [1] [j + 1], MOD); |
---|
2253 | else |
---|
2254 | tmp[0] += mulMod (bufFactors [0], bufFactors [1] [j + 1], MOD); |
---|
2255 | } |
---|
2256 | Pi [0] += tmp[0]*xToJ*F.mvar(); |
---|
2257 | |
---|
2258 | // update Pi [l] |
---|
2259 | int degPi, degBuf; |
---|
2260 | for (int l= 1; l < factors.length() - 1; l++) |
---|
2261 | { |
---|
2262 | degPi= degree (Pi [l - 1], x); |
---|
2263 | degBuf= degree (bufFactors[l + 1], x); |
---|
2264 | if (degPi > 0 && degBuf > 0) |
---|
2265 | M (j + 1, l + 1)= mulMod (Pi [l - 1] [j], bufFactors[l + 1] [j], MOD); |
---|
2266 | if (j == 1) |
---|
2267 | { |
---|
2268 | if (degPi > 0 && degBuf > 0) |
---|
2269 | Pi [l] += xToJ*(mulMod ((Pi [l - 1] [0] + Pi [l - 1] [j]), |
---|
2270 | (bufFactors[l + 1] [0] + buf[l + 1]), MOD) - M (j + 1, l +1)- |
---|
2271 | M (1, l + 1)); |
---|
2272 | else if (degPi > 0) |
---|
2273 | Pi [l] += xToJ*(mulMod (Pi [l - 1] [j], bufFactors[l + 1], MOD)); |
---|
2274 | else if (degBuf > 0) |
---|
2275 | Pi [l] += xToJ*(mulMod (Pi [l - 1], buf[l + 1], MOD)); |
---|
2276 | } |
---|
2277 | else |
---|
2278 | { |
---|
2279 | if (degPi > 0 && degBuf > 0) |
---|
2280 | { |
---|
2281 | uIZeroJ= mulMod (uIZeroJ, bufFactors [l + 1] [0], MOD); |
---|
2282 | uIZeroJ += mulMod (Pi [l - 1] [0], buf [l + 1], MOD); |
---|
2283 | } |
---|
2284 | else if (degPi > 0) |
---|
2285 | uIZeroJ= mulMod (uIZeroJ, bufFactors [l + 1], MOD); |
---|
2286 | else if (degBuf > 0) |
---|
2287 | { |
---|
2288 | uIZeroJ= mulMod (uIZeroJ, bufFactors [l + 1] [0], MOD); |
---|
2289 | uIZeroJ += mulMod (Pi [l - 1], buf[l + 1], MOD); |
---|
2290 | } |
---|
2291 | Pi[l] += xToJ*uIZeroJ; |
---|
2292 | } |
---|
2293 | one= bufFactors [l + 1]; |
---|
2294 | two= Pi [l - 1]; |
---|
2295 | if (two.exp() == j + 1) |
---|
2296 | { |
---|
2297 | if (degBuf > 0 && degPi > 0) |
---|
2298 | { |
---|
2299 | tmp[l] += mulMod (two.coeff(), bufFactors[l + 1][0], MOD); |
---|
2300 | two++; |
---|
2301 | } |
---|
2302 | else if (degPi > 0) |
---|
2303 | { |
---|
2304 | tmp[l] += mulMod (two.coeff(), bufFactors[l + 1], MOD); |
---|
2305 | two++; |
---|
2306 | } |
---|
2307 | } |
---|
2308 | if (degBuf > 0 && degPi > 0) |
---|
2309 | { |
---|
2310 | for (k= 1; k <= (int) ceil (j/2.0); k++) |
---|
2311 | { |
---|
2312 | if (k != j - k + 1) |
---|
2313 | { |
---|
2314 | if (one.exp() == j - k + 1 && two.exp() == j - k + 1) |
---|
2315 | { |
---|
2316 | tmp[l] += mulMod ((bufFactors[l + 1] [k] + one.coeff()), |
---|
2317 | (Pi[l - 1] [k] + two.coeff()), MOD) - M (k + 1, l + 1) - |
---|
2318 | M (j - k + 2, l + 1); |
---|
2319 | one++; |
---|
2320 | two++; |
---|
2321 | } |
---|
2322 | else if (one.exp() == j - k + 1) |
---|
2323 | { |
---|
2324 | tmp[l] += mulMod ((bufFactors[l + 1] [k] + one.coeff()), |
---|
2325 | Pi[l - 1] [k], MOD) - M (k + 1, l + 1); |
---|
2326 | one++; |
---|
2327 | } |
---|
2328 | else if (two.exp() == j - k + 1) |
---|
2329 | { |
---|
2330 | tmp[l] += mulMod (bufFactors[l + 1] [k], |
---|
2331 | (Pi[l - 1] [k] + two.coeff()), MOD) - M (k + 1, l + 1); |
---|
2332 | two++; |
---|
2333 | } |
---|
2334 | } |
---|
2335 | else |
---|
2336 | tmp[l] += M (k + 1, l + 1); |
---|
2337 | } |
---|
2338 | } |
---|
2339 | Pi[l] += tmp[l]*xToJ*F.mvar(); |
---|
2340 | } |
---|
2341 | |
---|
2342 | return; |
---|
2343 | } |
---|
2344 | |
---|
2345 | // wrt. Variable (1) |
---|
2346 | CanonicalForm replaceLC (const CanonicalForm& F, const CanonicalForm& c) |
---|
2347 | { |
---|
2348 | if (degree (F, 1) <= 0) |
---|
2349 | return c; |
---|
2350 | else |
---|
2351 | { |
---|
2352 | CanonicalForm result= swapvar (F, Variable (F.level() + 1), Variable (1)); |
---|
2353 | result += (swapvar (c, Variable (F.level() + 1), Variable (1)) |
---|
2354 | - LC (result))*power (result.mvar(), degree (result)); |
---|
2355 | return swapvar (result, Variable (F.level() + 1), Variable (1)); |
---|
2356 | } |
---|
2357 | } |
---|
2358 | |
---|
2359 | // so far only for two factor Hensel lifting |
---|
2360 | CFList |
---|
2361 | henselLift232 (const CFList& eval, const CFList& factors, int* l, CFList& |
---|
2362 | diophant, CFArray& Pi, CFMatrix& M, const CFList& LCs1, |
---|
2363 | const CFList& LCs2) |
---|
2364 | { |
---|
2365 | CFList buf= factors; |
---|
2366 | int k= 0; |
---|
2367 | int liftBoundBivar= l[k]; |
---|
2368 | CFList bufbuf= factors; |
---|
2369 | Variable v= Variable (2); |
---|
2370 | |
---|
2371 | CFList MOD; |
---|
2372 | MOD.append (power (Variable (2), liftBoundBivar)); |
---|
2373 | CFArray bufFactors= CFArray (factors.length()); |
---|
2374 | k= 0; |
---|
2375 | CFListIterator j= eval; |
---|
2376 | j++; |
---|
2377 | CFListIterator iter1= LCs1; |
---|
2378 | CFListIterator iter2= LCs2; |
---|
2379 | iter1++; |
---|
2380 | iter2++; |
---|
2381 | bufFactors[0]= replaceLC (buf.getFirst(), iter1.getItem()); |
---|
2382 | bufFactors[1]= replaceLC (buf.getLast(), iter2.getItem()); |
---|
2383 | |
---|
2384 | CFListIterator i= buf; |
---|
2385 | i++; |
---|
2386 | Variable y= j.getItem().mvar(); |
---|
2387 | if (y.level() != 3) |
---|
2388 | y= Variable (3); |
---|
2389 | |
---|
2390 | Pi[0]= mod (Pi[0], power (v, liftBoundBivar)); |
---|
2391 | M (1, 1)= Pi[0]; |
---|
2392 | if (degree (bufFactors[0], y) > 0 && degree (bufFactors [1], y) > 0) |
---|
2393 | Pi [0] += (mulMod (bufFactors [0] [1], bufFactors[1] [0], MOD) + |
---|
2394 | mulMod (bufFactors [0] [0], bufFactors [1] [1], MOD))*y; |
---|
2395 | else if (degree (bufFactors[0], y) > 0) |
---|
2396 | Pi [0] += mulMod (bufFactors [0] [1], bufFactors[1], MOD)*y; |
---|
2397 | else if (degree (bufFactors[1], y) > 0) |
---|
2398 | Pi [0] += mulMod (bufFactors [0], bufFactors[1] [1], MOD)*y; |
---|
2399 | |
---|
2400 | CFList products; |
---|
2401 | for (int i= 0; i < bufFactors.size(); i++) |
---|
2402 | { |
---|
2403 | if (degree (bufFactors[i], y) > 0) |
---|
2404 | products.append (M (1, 1)/bufFactors[i] [0]); |
---|
2405 | else |
---|
2406 | products.append (M (1, 1)/bufFactors[i]); |
---|
2407 | } |
---|
2408 | |
---|
2409 | for (int d= 1; d < l[1]; d++) |
---|
2410 | henselStep2 (j.getItem(), buf, bufFactors, diophant, M, Pi, products, d, MOD); |
---|
2411 | CFList result; |
---|
2412 | for (k= 0; k < factors.length(); k++) |
---|
2413 | result.append (bufFactors[k]); |
---|
2414 | return result; |
---|
2415 | } |
---|
2416 | |
---|
2417 | |
---|
2418 | CFList |
---|
2419 | henselLift2 (const CFList& F, const CFList& factors, const CFList& MOD, CFList& |
---|
2420 | diophant, CFArray& Pi, CFMatrix& M, const int lOld, int& |
---|
2421 | lNew, const CFList& LCs1, const CFList& LCs2) |
---|
2422 | { |
---|
2423 | int k= 0; |
---|
2424 | CFArray bufFactors= CFArray (factors.length()); |
---|
2425 | bufFactors[0]= replaceLC (factors.getFirst(), LCs1.getLast()); |
---|
2426 | bufFactors[1]= replaceLC (factors.getLast(), LCs2.getLast()); |
---|
2427 | CFList buf= factors; |
---|
2428 | Variable y= F.getLast().mvar(); |
---|
2429 | Variable x= F.getFirst().mvar(); |
---|
2430 | CanonicalForm xToLOld= power (x, lOld); |
---|
2431 | Pi [0]= mod (Pi[0], xToLOld); |
---|
2432 | M (1, 1)= Pi [0]; |
---|
2433 | |
---|
2434 | if (degree (bufFactors[0], y) > 0 && degree (bufFactors [1], y) > 0) |
---|
2435 | Pi [0] += (mulMod (bufFactors [0] [1], bufFactors[1] [0], MOD) + |
---|
2436 | mulMod (bufFactors [0] [0], bufFactors [1] [1], MOD))*y; |
---|
2437 | else if (degree (bufFactors[0], y) > 0) |
---|
2438 | Pi [0] += mulMod (bufFactors [0] [1], bufFactors[1], MOD)*y; |
---|
2439 | else if (degree (bufFactors[1], y) > 0) |
---|
2440 | Pi [0] += mulMod (bufFactors [0], bufFactors[1] [1], MOD)*y; |
---|
2441 | |
---|
2442 | CFList products; |
---|
2443 | for (int i= 0; i < bufFactors.size(); i++) |
---|
2444 | { |
---|
2445 | if (degree (bufFactors[i], y) > 0) |
---|
2446 | { |
---|
2447 | ASSERT (fdivides (bufFactors[i][0], M (1, 1)), "expected exact division"); |
---|
2448 | products.append (M (1, 1)/bufFactors[i] [0]); |
---|
2449 | } |
---|
2450 | else |
---|
2451 | { |
---|
2452 | ASSERT (fdivides (bufFactors[i], M (1, 1)), "expected exact division"); |
---|
2453 | products.append (M (1, 1)/bufFactors[i]); |
---|
2454 | } |
---|
2455 | } |
---|
2456 | |
---|
2457 | for (int d= 1; d < lNew; d++) |
---|
2458 | henselStep2 (F.getLast(),buf,bufFactors, diophant, M, Pi, products, d, MOD); |
---|
2459 | |
---|
2460 | CFList result; |
---|
2461 | for (k= 0; k < factors.length(); k++) |
---|
2462 | result.append (bufFactors[k]); |
---|
2463 | return result; |
---|
2464 | } |
---|
2465 | |
---|
2466 | // so far only for two! factor Hensel lifting |
---|
2467 | CFList |
---|
2468 | henselLift2 (const CFList& eval, const CFList& factors, int* l, const int |
---|
2469 | lLength, bool sort, const CFList& LCs1, const CFList& LCs2, |
---|
2470 | const CFArray& Pi, const CFList& diophant) |
---|
2471 | { |
---|
2472 | CFList bufDiophant= diophant; |
---|
2473 | CFList buf= factors; |
---|
2474 | if (sort) |
---|
2475 | sortList (buf, Variable (1)); |
---|
2476 | CFArray bufPi= Pi; |
---|
2477 | CFMatrix M= CFMatrix (l[1], factors.length()); |
---|
2478 | CFList result= henselLift232(eval, buf, l, bufDiophant, bufPi, M, LCs1, LCs2); |
---|
2479 | if (eval.length() == 2) |
---|
2480 | return result; |
---|
2481 | CFList MOD; |
---|
2482 | for (int i= 0; i < 2; i++) |
---|
2483 | MOD.append (power (Variable (i + 2), l[i])); |
---|
2484 | CFListIterator j= eval; |
---|
2485 | j++; |
---|
2486 | CFList bufEval; |
---|
2487 | bufEval.append (j.getItem()); |
---|
2488 | j++; |
---|
2489 | CFListIterator jj= LCs1; |
---|
2490 | CFListIterator jjj= LCs2; |
---|
2491 | CFList bufLCs1, bufLCs2; |
---|
2492 | jj++, jjj++; |
---|
2493 | bufLCs1.append (jj.getItem()); |
---|
2494 | bufLCs2.append (jjj.getItem()); |
---|
2495 | jj++, jjj++; |
---|
2496 | |
---|
2497 | for (int i= 2; i < lLength && j.hasItem(); i++, j++, jj++, jjj++) |
---|
2498 | { |
---|
2499 | bufEval.append (j.getItem()); |
---|
2500 | bufLCs1.append (jj.getItem()); |
---|
2501 | bufLCs2.append (jjj.getItem()); |
---|
2502 | M= CFMatrix (l[i], factors.length()); |
---|
2503 | result= henselLift2 (bufEval, result, MOD, bufDiophant, bufPi, M, l[i - 1], |
---|
2504 | l[i], bufLCs1, bufLCs2); |
---|
2505 | MOD.append (power (Variable (i + 2), l[i])); |
---|
2506 | bufEval.removeFirst(); |
---|
2507 | bufLCs1.removeFirst(); |
---|
2508 | bufLCs2.removeFirst(); |
---|
2509 | } |
---|
2510 | return result; |
---|
2511 | } |
---|
2512 | |
---|
2513 | #endif |
---|
2514 | /* HAVE_NTL */ |
---|
2515 | |
---|