1 | /* emacs edit mode for this file is -*- C++ -*- */ |
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2 | |
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3 | /** |
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4 | * |
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5 | * @file cf_factor.cc |
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6 | * |
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7 | * Interface to factorization and square free factorization algorithms. |
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8 | * |
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9 | * Used by: cf_irred.cc |
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10 | * |
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11 | * Header file: cf_algorithm.h |
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12 | * |
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13 | **/ |
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14 | |
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15 | |
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16 | #include "config.h" |
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17 | |
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18 | |
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19 | #include "cf_assert.h" |
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20 | |
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21 | #include "cf_defs.h" |
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22 | #include "canonicalform.h" |
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23 | #include "cf_iter.h" |
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24 | #include "fac_sqrfree.h" |
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25 | #include "cf_algorithm.h" |
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26 | #include "facFqFactorize.h" |
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27 | #include "facFqSquarefree.h" |
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28 | #include "cf_map.h" |
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29 | #include "facAlgExt.h" |
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30 | #include "facFactorize.h" |
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31 | #include "singext.h" |
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32 | #include "cf_util.h" |
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33 | #include "fac_berlekamp.h" |
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34 | #include "fac_cantzass.h" |
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35 | #include "fac_univar.h" |
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36 | #include "fac_multivar.h" |
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37 | |
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38 | #include "int_int.h" |
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39 | #ifdef HAVE_NTL |
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40 | #include "NTLconvert.h" |
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41 | #endif |
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42 | |
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43 | #include "factory/cf_gmp.h" |
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44 | #ifdef HAVE_FLINT |
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45 | #include "FLINTconvert.h" |
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46 | #if (__FLINT_RELEASE >= 20700) |
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47 | #include <flint/nmod_mpoly_factor.h> |
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48 | #include <flint/fmpq_mpoly_factor.h> |
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49 | #endif |
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50 | #endif |
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51 | |
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52 | //static bool isUnivariateBaseDomain( const CanonicalForm & f ) |
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53 | //{ |
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54 | // CFIterator i = f; |
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55 | // bool ok = i.coeff().inBaseDomain(); |
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56 | // i++; |
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57 | // while ( i.hasTerms() && ( ok = ok && i.coeff().inBaseDomain() ) ) i++; |
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58 | // return ok; |
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59 | //} |
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60 | |
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61 | void find_exp(const CanonicalForm & f, int * exp_f) |
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62 | { |
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63 | if ( ! f.inCoeffDomain() ) |
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64 | { |
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65 | int e=f.level(); |
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66 | CFIterator i = f; |
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67 | if (e>=0) |
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68 | { |
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69 | if (i.exp() > exp_f[e]) exp_f[e]=i.exp(); |
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70 | } |
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71 | for (; i.hasTerms(); i++ ) |
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72 | { |
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73 | find_exp(i.coeff(), exp_f); |
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74 | } |
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75 | } |
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76 | } |
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77 | |
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78 | int find_mvar(const CanonicalForm & f) |
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79 | { |
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80 | int mv=f.level(); |
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81 | int *exp_f=NEW_ARRAY(int,mv+1); |
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82 | int i; |
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83 | for(i=mv;i>0;i--) exp_f[i]=0; |
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84 | find_exp(f,exp_f); |
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85 | for(i=mv;i>0;i--) |
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86 | { |
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87 | if ((exp_f[i]>0) && (exp_f[i]<exp_f[mv])) |
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88 | { |
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89 | mv=i; |
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90 | } |
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91 | } |
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92 | DELETE_ARRAY(exp_f); |
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93 | return mv; |
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94 | } |
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95 | |
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96 | #if 1 |
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97 | //#ifndef NOSTREAMIO |
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98 | void out_cf(const char *s1,const CanonicalForm &f,const char *s2) |
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99 | { |
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100 | printf("%s",s1); |
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101 | if (f.isZero()) printf("+0"); |
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102 | //else if (! f.inCoeffDomain() ) |
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103 | else if (! f.inBaseDomain() ) |
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104 | { |
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105 | int l = f.level(); |
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106 | for ( CFIterator i = f; i.hasTerms(); i++ ) |
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107 | { |
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108 | int e=i.exp(); |
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109 | if (i.coeff().isOne()) |
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110 | { |
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111 | printf("+"); |
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112 | if (e==0) printf("1"); |
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113 | else |
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114 | { |
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115 | printf("%c",'a'+l-1); |
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116 | if (e!=1) printf("^%d",e); |
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117 | } |
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118 | } |
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119 | else |
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120 | { |
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121 | out_cf("+(",i.coeff(),")"); |
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122 | if (e!=0) |
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123 | { |
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124 | printf("*%c",'a'+l-1); |
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125 | if (e!=1) printf("^%d",e); |
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126 | } |
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127 | } |
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128 | } |
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129 | } |
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130 | else |
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131 | { |
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132 | if ( f.isImm() ) |
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133 | { |
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134 | if (CFFactory::gettype()==GaloisFieldDomain) |
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135 | { |
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136 | long a= imm2int (f.getval()); |
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137 | if ( a == gf_q ) |
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138 | printf ("+%ld", a); |
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139 | else if ( a == 0L ) |
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140 | printf ("+1"); |
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141 | else if ( a == 1L ) |
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142 | printf ("+%c",gf_name); |
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143 | else |
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144 | { |
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145 | printf ("+%c",gf_name); |
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146 | printf ("^%ld",a); |
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147 | } |
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148 | } |
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149 | else |
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150 | { |
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151 | long l=f.intval(); |
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152 | if (l<0) printf("%ld",l); |
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153 | else printf("+%ld",l); |
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154 | } |
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155 | } |
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156 | else |
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157 | { |
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158 | #ifdef NOSTREAMIO |
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159 | if (f.inZ()) |
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160 | { |
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161 | mpz_t m; |
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162 | gmp_numerator(f,m); |
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163 | char * str = new char[mpz_sizeinbase( m, 10 ) + 2]; |
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164 | str = mpz_get_str( str, 10, m ); |
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165 | puts(str); |
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166 | delete[] str; |
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167 | mpz_clear(m); |
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168 | } |
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169 | else if (f.inQ()) |
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170 | { |
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171 | mpz_t m; |
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172 | gmp_numerator(f,m); |
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173 | char * str = new char[mpz_sizeinbase( m, 10 ) + 2]; |
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174 | str = mpz_get_str( str, 10, m ); |
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175 | while(str[strlen(str)]<' ') { str[strlen(str)]='\0'; } |
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176 | puts(str);putchar('/'); |
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177 | delete[] str; |
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178 | mpz_clear(m); |
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179 | gmp_denominator(f,m); |
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180 | str = new char[mpz_sizeinbase( m, 10 ) + 2]; |
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181 | str = mpz_get_str( str, 10, m ); |
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182 | while(str[strlen(str)]<' ') { str[strlen(str)]='\0'; } |
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183 | puts(str); |
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184 | delete[] str; |
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185 | mpz_clear(m); |
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186 | } |
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187 | #else |
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188 | std::cout << f; |
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189 | #endif |
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190 | } |
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191 | //if (f.inZ()) printf("(Z)"); |
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192 | //else if (f.inQ()) printf("(Q)"); |
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193 | //else if (f.inFF()) printf("(FF)"); |
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194 | //else if (f.inPP()) printf("(PP)"); |
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195 | //else if (f.inGF()) printf("(PP)"); |
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196 | //else |
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197 | if (f.inExtension()) printf("E(%d)",f.level()); |
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198 | } |
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199 | printf("%s",s2); |
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200 | } |
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201 | void out_cff(CFFList &L) |
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202 | { |
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203 | //int n = L.length(); |
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204 | CFFListIterator J=L; |
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205 | int j=0; |
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206 | for ( ; J.hasItem(); J++, j++ ) |
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207 | { |
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208 | printf("F%d",j);out_cf(":",J.getItem().factor()," ^ "); |
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209 | printf("%d\n", J.getItem().exp()); |
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210 | } |
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211 | } |
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212 | void test_cff(CFFList &L,const CanonicalForm & f) |
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213 | { |
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214 | //int n = L.length(); |
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215 | CFFListIterator J=L; |
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216 | CanonicalForm t=1; |
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217 | int j=0; |
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218 | if (!(L.getFirst().factor().inCoeffDomain())) |
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219 | printf("first entry is not const\n"); |
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220 | for ( ; J.hasItem(); J++, j++ ) |
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221 | { |
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222 | CanonicalForm tt=J.getItem().factor(); |
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223 | if (tt.inCoeffDomain() && (j!=0)) |
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224 | printf("other entry is const\n"); |
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225 | j=J.getItem().exp(); |
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226 | while(j>0) { t*=tt; j--; } |
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227 | } |
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228 | if (!(f-t).isZero()) { printf("problem:\n");out_cf("factor:",f," has problems\n");} |
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229 | } |
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230 | //#endif |
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231 | #endif |
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232 | |
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233 | bool isPurePoly_m(const CanonicalForm & f) |
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234 | { |
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235 | if (f.inBaseDomain()) return true; |
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236 | if (f.level()<0) return false; |
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237 | for (CFIterator i=f;i.hasTerms();i++) |
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238 | { |
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239 | if (!isPurePoly_m(i.coeff())) return false; |
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240 | } |
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241 | return true; |
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242 | } |
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243 | bool isPurePoly(const CanonicalForm & f) |
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244 | { |
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245 | if (f.level()<=0) return false; |
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246 | for (CFIterator i=f;i.hasTerms();i++) |
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247 | { |
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248 | if (!(i.coeff().inBaseDomain())) return false; |
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249 | } |
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250 | return true; |
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251 | } |
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252 | |
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253 | |
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254 | /** |
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255 | * get_max_degree_Variable returns Variable with |
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256 | * highest degree. We assume f is *not* a constant! |
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257 | **/ |
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258 | Variable |
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259 | get_max_degree_Variable(const CanonicalForm & f) |
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260 | { |
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261 | ASSERT( ( ! f.inCoeffDomain() ), "no constants" ); |
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262 | int max=0, maxlevel=0, n=level(f); |
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263 | for ( int i=1; i<=n; i++ ) |
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264 | { |
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265 | if (degree(f,Variable(i)) >= max) |
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266 | { |
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267 | max= degree(f,Variable(i)); maxlevel= i; |
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268 | } |
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269 | } |
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270 | return Variable(maxlevel); |
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271 | } |
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272 | |
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273 | /** |
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274 | * get_Terms: Split the polynomial in the containing terms. |
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275 | * getTerms: the real work is done here. |
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276 | **/ |
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277 | void |
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278 | getTerms( const CanonicalForm & f, const CanonicalForm & t, CFList & result ) |
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279 | { |
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280 | if ( getNumVars(f) == 0 ) result.append(f*t); |
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281 | else{ |
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282 | Variable x(level(f)); |
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283 | for ( CFIterator i=f; i.hasTerms(); i++ ) |
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284 | getTerms( i.coeff(), t*power(x,i.exp()), result); |
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285 | } |
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286 | } |
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287 | CFList |
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288 | get_Terms( const CanonicalForm & f ){ |
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289 | CFList result,dummy,dummy2; |
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290 | CFIterator i; |
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291 | CFListIterator j; |
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292 | |
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293 | if ( getNumVars(f) == 0 ) result.append(f); |
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294 | else{ |
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295 | Variable _x(level(f)); |
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296 | for ( i=f; i.hasTerms(); i++ ){ |
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297 | getTerms(i.coeff(), 1, dummy); |
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298 | for ( j=dummy; j.hasItem(); j++ ) |
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299 | result.append(j.getItem() * power(_x, i.exp())); |
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300 | |
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301 | dummy= dummy2; // have to initalize new |
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302 | } |
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303 | } |
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304 | return result; |
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305 | } |
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306 | |
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307 | |
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308 | /** |
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309 | * homogenize homogenizes f with Variable x |
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310 | **/ |
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311 | CanonicalForm |
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312 | homogenize( const CanonicalForm & f, const Variable & x) |
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313 | { |
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314 | #if 0 |
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315 | int maxdeg=totaldegree(f), deg; |
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316 | CFIterator i; |
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317 | CanonicalForm elem, result(0); |
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318 | |
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319 | for (i=f; i.hasTerms(); i++) |
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320 | { |
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321 | elem= i.coeff()*power(f.mvar(),i.exp()); |
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322 | deg = totaldegree(elem); |
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323 | if ( deg < maxdeg ) |
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324 | result += elem * power(x,maxdeg-deg); |
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325 | else |
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326 | result+=elem; |
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327 | } |
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328 | return result; |
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329 | #else |
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330 | CFList Newlist, Termlist= get_Terms(f); |
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331 | int maxdeg=totaldegree(f), deg; |
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332 | CFListIterator i; |
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333 | CanonicalForm elem, result(0); |
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334 | |
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335 | for (i=Termlist; i.hasItem(); i++) |
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336 | { |
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337 | elem= i.getItem(); |
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338 | deg = totaldegree(elem); |
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339 | if ( deg < maxdeg ) |
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340 | Newlist.append(elem * power(x,maxdeg-deg)); |
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341 | else |
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342 | Newlist.append(elem); |
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343 | } |
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344 | for (i=Newlist; i.hasItem(); i++) // rebuild |
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345 | result += i.getItem(); |
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346 | |
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347 | return result; |
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348 | #endif |
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349 | } |
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350 | |
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351 | CanonicalForm |
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352 | homogenize( const CanonicalForm & f, const Variable & x, const Variable & v1, const Variable & v2) |
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353 | { |
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354 | #if 0 |
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355 | int maxdeg=totaldegree(f), deg; |
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356 | CFIterator i; |
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357 | CanonicalForm elem, result(0); |
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358 | |
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359 | for (i=f; i.hasTerms(); i++) |
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360 | { |
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361 | elem= i.coeff()*power(f.mvar(),i.exp()); |
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362 | deg = totaldegree(elem); |
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363 | if ( deg < maxdeg ) |
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364 | result += elem * power(x,maxdeg-deg); |
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365 | else |
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366 | result+=elem; |
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367 | } |
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368 | return result; |
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369 | #else |
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370 | CFList Newlist, Termlist= get_Terms(f); |
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371 | int maxdeg=totaldegree(f), deg; |
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372 | CFListIterator i; |
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373 | CanonicalForm elem, result(0); |
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374 | |
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375 | for (i=Termlist; i.hasItem(); i++) |
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376 | { |
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377 | elem= i.getItem(); |
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378 | deg = totaldegree(elem,v1,v2); |
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379 | if ( deg < maxdeg ) |
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380 | Newlist.append(elem * power(x,maxdeg-deg)); |
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381 | else |
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382 | Newlist.append(elem); |
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383 | } |
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384 | for (i=Newlist; i.hasItem(); i++) // rebuild |
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385 | result += i.getItem(); |
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386 | |
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387 | return result; |
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388 | #endif |
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389 | } |
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390 | |
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391 | VAR int singular_homog_flag=1; |
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392 | |
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393 | int cmpCF( const CFFactor & f, const CFFactor & g ) |
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394 | { |
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395 | if (f.exp() > g.exp()) return 1; |
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396 | if (f.exp() < g.exp()) return 0; |
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397 | if (f.factor() > g.factor()) return 1; |
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398 | return 0; |
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399 | } |
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400 | |
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401 | /** |
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402 | * factorization over \f$ F_p \f$ or \f$ Q \f$ |
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403 | **/ |
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404 | CFFList factorize ( const CanonicalForm & f, bool issqrfree ) |
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405 | { |
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406 | if ( f.inCoeffDomain() ) |
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407 | return CFFList( f ); |
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408 | #ifndef NOASSERT |
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409 | Variable a; |
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410 | ASSERT (!hasFirstAlgVar (f, a), "f has an algebraic variable use factorize \ |
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411 | ( const CanonicalForm & f, const Variable & alpha ) instead"); |
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412 | #endif |
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413 | //out_cf("factorize:",f,"==================================\n"); |
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414 | if (! f.isUnivariate() ) // preprocess homog. polys |
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415 | { |
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416 | if ( singular_homog_flag && f.isHomogeneous()) |
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417 | { |
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418 | Variable xn = get_max_degree_Variable(f); |
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419 | int d_xn = degree(f,xn); |
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420 | CFMap n; |
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421 | CanonicalForm F = compress(f(1,xn),n); |
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422 | CFFList Intermediatelist; |
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423 | Intermediatelist = factorize(F); |
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424 | CFFList Homoglist; |
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425 | CFFListIterator j; |
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426 | for ( j=Intermediatelist; j.hasItem(); j++ ) |
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427 | { |
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428 | Homoglist.append( |
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429 | CFFactor( n(j.getItem().factor()), j.getItem().exp()) ); |
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430 | } |
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431 | CFFList Unhomoglist; |
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432 | CanonicalForm unhomogelem; |
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433 | for ( j=Homoglist; j.hasItem(); j++ ) |
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434 | { |
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435 | unhomogelem= homogenize(j.getItem().factor(),xn); |
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436 | Unhomoglist.append(CFFactor(unhomogelem,j.getItem().exp())); |
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437 | d_xn -= (degree(unhomogelem,xn)*j.getItem().exp()); |
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438 | } |
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439 | if ( d_xn != 0 ) // have to append xn^(d_xn) |
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440 | Unhomoglist.append(CFFactor(CanonicalForm(xn),d_xn)); |
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441 | if(isOn(SW_USE_NTL_SORT)) Unhomoglist.sort(cmpCF); |
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442 | return Unhomoglist; |
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443 | } |
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444 | } |
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445 | CFFList F; |
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446 | if ( getCharacteristic() > 0 ) |
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447 | { |
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448 | if (f.isUnivariate()) |
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449 | { |
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450 | #ifdef HAVE_FLINT |
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451 | #ifdef HAVE_NTL |
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452 | if (degree (f) < 300) |
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453 | #endif |
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454 | { |
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455 | // use FLINT: char p, univariate |
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456 | nmod_poly_t f1; |
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457 | convertFacCF2nmod_poly_t (f1, f); |
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458 | nmod_poly_factor_t result; |
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459 | nmod_poly_factor_init (result); |
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460 | mp_limb_t leadingCoeff= nmod_poly_factor (result, f1); |
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461 | F= convertFLINTnmod_poly_factor2FacCFFList (result, leadingCoeff, f.mvar()); |
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462 | nmod_poly_factor_clear (result); |
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463 | nmod_poly_clear (f1); |
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464 | if(isOn(SW_USE_NTL_SORT)) F.sort(cmpCF); |
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465 | return F; |
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466 | } |
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467 | #endif |
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468 | #ifdef HAVE_NTL |
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469 | { // NTL char 2, univariate |
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470 | if (getCharacteristic()==2) |
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471 | { |
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472 | // Specialcase characteristic==2 |
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473 | if (fac_NTL_char != 2) |
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474 | { |
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475 | fac_NTL_char = 2; |
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476 | zz_p::init(2); |
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477 | } |
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478 | // convert to NTL using the faster conversion routine for characteristic 2 |
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479 | GF2X f1=convertFacCF2NTLGF2X(f); |
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480 | // no make monic necessary in GF2 |
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481 | //factorize |
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482 | vec_pair_GF2X_long factors; |
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483 | CanZass(factors,f1); |
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484 | |
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485 | // convert back to factory again using the faster conversion routine for vectors over GF2X |
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486 | F=convertNTLvec_pair_GF2X_long2FacCFFList(factors,LeadCoeff(f1),f.mvar()); |
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487 | if(isOn(SW_USE_NTL_SORT)) F.sort(cmpCF); |
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488 | return F; |
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489 | } |
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490 | } |
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491 | #endif |
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492 | #ifdef HAVE_NTL |
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493 | { |
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494 | // use NTL char p, univariate |
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495 | if (fac_NTL_char != getCharacteristic()) |
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496 | { |
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497 | fac_NTL_char = getCharacteristic(); |
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498 | zz_p::init(getCharacteristic()); |
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499 | } |
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500 | |
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501 | // convert to NTL |
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502 | zz_pX f1=convertFacCF2NTLzzpX(f); |
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503 | zz_p leadcoeff = LeadCoeff(f1); |
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504 | |
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505 | //make monic |
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506 | f1=f1 / LeadCoeff(f1); |
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507 | // factorize |
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508 | vec_pair_zz_pX_long factors; |
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509 | CanZass(factors,f1); |
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510 | |
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511 | F=convertNTLvec_pair_zzpX_long2FacCFFList(factors,leadcoeff,f.mvar()); |
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512 | //test_cff(F,f); |
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513 | if(isOn(SW_USE_NTL_SORT)) F.sort(cmpCF); |
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514 | return F; |
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515 | } |
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516 | #endif |
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517 | #if !defined(HAVE_NTL) && !defined(HAVE_FLINT) |
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518 | // Use Factory without NTL and without FLINT: char p, univariate |
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519 | { |
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520 | if ( isOn( SW_BERLEKAMP ) ) |
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521 | F=FpFactorizeUnivariateB( f, issqrfree ); |
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522 | else |
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523 | F=FpFactorizeUnivariateCZ( f, issqrfree, 0, Variable(), Variable() ); |
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524 | return F; |
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525 | } |
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526 | #endif |
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527 | } |
---|
528 | else // char p, multivariate |
---|
529 | { |
---|
530 | #if defined(HAVE_NTL) |
---|
531 | if (issqrfree) |
---|
532 | { |
---|
533 | CFList factors; |
---|
534 | Variable alpha; |
---|
535 | if (CFFactory::gettype() == GaloisFieldDomain) |
---|
536 | factors= GFSqrfFactorize (f); |
---|
537 | else |
---|
538 | factors= FpSqrfFactorize (f); |
---|
539 | for (CFListIterator i= factors; i.hasItem(); i++) |
---|
540 | F.append (CFFactor (i.getItem(), 1)); |
---|
541 | } |
---|
542 | else |
---|
543 | { |
---|
544 | Variable alpha; |
---|
545 | if (CFFactory::gettype() == GaloisFieldDomain) |
---|
546 | F= GFFactorize (f); |
---|
547 | else |
---|
548 | F= FpFactorize (f); |
---|
549 | } |
---|
550 | #elif defined(HAVE_FLINT) && (__FLINT_RELEASE >= 20700) |
---|
551 | #if 0 |
---|
552 | nmod_mpoly_ctx_t ctx; |
---|
553 | nmod_mpoly_ctx_init(ctx,f.level(),ORD_LEX,getCharacteristic()); |
---|
554 | nmod_mpoly_t Flint_f; |
---|
555 | nmod_mpoly_init(Flint_f,ctx); |
---|
556 | convFactoryPFlintMP(f,Flint_f,ctx,f.level()); |
---|
557 | nmod_mpoly_factor_t factors; |
---|
558 | nmod_mpoly_factor_init(factors,ctx); |
---|
559 | if (issqrfree) nmod_mpoly_factor_squarefree(factors,Flint_f,ctx); |
---|
560 | else nmod_mpoly_factor(factors,Flint_f,ctx); |
---|
561 | nmod_mpoly_t fac; |
---|
562 | nmod_mpoly_init(fac,ctx); |
---|
563 | CanonicalForm cf_fac; |
---|
564 | int cf_exp; |
---|
565 | cf_fac=nmod_mpoly_factor_get_constant_ui(factors,ctx); |
---|
566 | F.append(CFFactor(cf_fac,1)); |
---|
567 | for(int i=nmod_mpoly_factor_length(factors,ctx)-1; i>=0; i--) |
---|
568 | { |
---|
569 | nmod_mpoly_factor_get_base(fac,factors,i,ctx); |
---|
570 | cf_fac=convFlintMPFactoryP(fac,ctx,f.level()); |
---|
571 | cf_exp=nmod_mpoly_factor_get_exp_si(factors,i,ctx); |
---|
572 | F.append(CFFactor(cf_fac,cf_exp)); |
---|
573 | } |
---|
574 | nmod_mpoly_factor_clear(factors,ctx); |
---|
575 | nmod_mpoly_clear(Flint_f,ctx); |
---|
576 | nmod_mpoly_ctx_clear(ctx); |
---|
577 | #endif |
---|
578 | #else |
---|
579 | factoryError ("multivariate factorization depends on NTL(missing)"); |
---|
580 | return CFFList (CFFactor (f, 1)); |
---|
581 | #endif |
---|
582 | } |
---|
583 | } |
---|
584 | else // char 0 |
---|
585 | { |
---|
586 | bool on_rational = isOn(SW_RATIONAL); |
---|
587 | On(SW_RATIONAL); |
---|
588 | CanonicalForm cd = bCommonDen( f ); |
---|
589 | CanonicalForm fz = f * cd; |
---|
590 | Off(SW_RATIONAL); |
---|
591 | if ( f.isUnivariate() ) |
---|
592 | { |
---|
593 | CanonicalForm ic=icontent(fz); |
---|
594 | fz/=ic; |
---|
595 | if (fz.degree()==1) |
---|
596 | { |
---|
597 | F=CFFList(CFFactor(fz,1)); |
---|
598 | F.insert(CFFactor(ic,1)); |
---|
599 | } |
---|
600 | else |
---|
601 | #if defined(HAVE_FLINT) && (__FLINT_RELEASE>=20503) && (__FLINT_RELEASE!= 20600) |
---|
602 | { |
---|
603 | // FLINT 2.6.0 has a bug: |
---|
604 | // factorize x^12-13*x^10-13*x^8+13*x^4+13*x^2-1 runs forever |
---|
605 | // use FLINT: char 0, univariate |
---|
606 | fmpz_poly_t f1; |
---|
607 | convertFacCF2Fmpz_poly_t (f1, fz); |
---|
608 | fmpz_poly_factor_t result; |
---|
609 | fmpz_poly_factor_init (result); |
---|
610 | fmpz_poly_factor(result, f1); |
---|
611 | F= convertFLINTfmpz_poly_factor2FacCFFList (result, fz.mvar()); |
---|
612 | fmpz_poly_factor_clear (result); |
---|
613 | fmpz_poly_clear (f1); |
---|
614 | if ( ! ic.isOne() ) |
---|
615 | { |
---|
616 | // according to convertFLINTfmpz_polyfactor2FcaCFFlist, |
---|
617 | // first entry is in CoeffDomain |
---|
618 | CFFactor new_first( F.getFirst().factor() * ic ); |
---|
619 | F.removeFirst(); |
---|
620 | F.insert( new_first ); |
---|
621 | } |
---|
622 | } |
---|
623 | goto end_char0; |
---|
624 | #elif defined(HAVE_NTL) |
---|
625 | { |
---|
626 | //use NTL |
---|
627 | ZZ c; |
---|
628 | vec_pair_ZZX_long factors; |
---|
629 | //factorize the converted polynomial |
---|
630 | factor(c,factors,convertFacCF2NTLZZX(fz)); |
---|
631 | |
---|
632 | //convert the result back to Factory |
---|
633 | F=convertNTLvec_pair_ZZX_long2FacCFFList(factors,c,fz.mvar()); |
---|
634 | if ( ! ic.isOne() ) |
---|
635 | { |
---|
636 | // according to convertNTLvec_pair_ZZX_long2FacCFFList |
---|
637 | // first entry is in CoeffDomain |
---|
638 | CFFactor new_first( F.getFirst().factor() * ic ); |
---|
639 | F.removeFirst(); |
---|
640 | F.insert( new_first ); |
---|
641 | } |
---|
642 | } |
---|
643 | goto end_char0; |
---|
644 | #else |
---|
645 | { |
---|
646 | //Use Factory without NTL: char 0, univariate |
---|
647 | F = ZFactorizeUnivariate( fz, issqrfree ); |
---|
648 | goto end_char0; |
---|
649 | } |
---|
650 | #endif |
---|
651 | } |
---|
652 | else // multivariate, char 0 |
---|
653 | { |
---|
654 | #if 0 //defined(HAVE_FLINT) && (__FLINT_RELEASE >= 20700) |
---|
655 | On (SW_RATIONAL); |
---|
656 | fmpq_mpoly_ctx_t ctx; |
---|
657 | fmpq_mpoly_ctx_init(ctx,f.level(),ORD_LEX); |
---|
658 | fmpq_mpoly_t Flint_f; |
---|
659 | fmpq_mpoly_init(Flint_f,ctx); |
---|
660 | convFactoryPFlintMP(fz,Flint_f,ctx,fz.level()); |
---|
661 | fmpq_mpoly_factor_t factors; |
---|
662 | fmpq_mpoly_factor_init(factors,ctx); |
---|
663 | int rr; |
---|
664 | if (issqrfree) rr=fmpq_mpoly_factor_squarefree(factors,Flint_f,ctx); |
---|
665 | else rr=fmpq_mpoly_factor(factors,Flint_f,ctx); |
---|
666 | if (rr==0) printf("fail\n"); |
---|
667 | fmpq_mpoly_t fac; |
---|
668 | fmpq_mpoly_init(fac,ctx); |
---|
669 | CanonicalForm cf_fac; |
---|
670 | int cf_exp; |
---|
671 | fmpq_t c; |
---|
672 | fmpq_init(c); |
---|
673 | fmpq_mpoly_factor_get_constant_fmpq(c,factors,ctx); |
---|
674 | cf_fac=convertFmpq2CF(c); |
---|
675 | fmpq_clear(c); |
---|
676 | if (!cf_fac.isOne()) F.append(CFFactor(cf_fac,1)); |
---|
677 | for(int i=fmpq_mpoly_factor_length(factors,ctx)-1; i>=0; i--) |
---|
678 | { |
---|
679 | fmpq_mpoly_factor_get_base(fac,factors,i,ctx); |
---|
680 | cf_fac=convFlintMPFactoryP(fac,ctx,f.level()); |
---|
681 | cf_exp=fmpq_mpoly_factor_get_exp_si(factors,i,ctx); |
---|
682 | F.append(CFFactor(cf_fac,cf_exp)); |
---|
683 | } |
---|
684 | fmpq_mpoly_factor_clear(factors,ctx); |
---|
685 | fmpq_mpoly_clear(Flint_f,ctx); |
---|
686 | fmpq_mpoly_ctx_clear(ctx); |
---|
687 | #elif defined(HAVE_NTL) |
---|
688 | On (SW_RATIONAL); |
---|
689 | if (issqrfree) |
---|
690 | { |
---|
691 | CFList factors= ratSqrfFactorize (fz); |
---|
692 | for (CFListIterator i= factors; i.hasItem(); i++) |
---|
693 | F.append (CFFactor (i.getItem(), 1)); |
---|
694 | } |
---|
695 | else |
---|
696 | { |
---|
697 | F = ratFactorize (fz); |
---|
698 | } |
---|
699 | #else |
---|
700 | F=ZFactorizeMultivariate(fz, issqrfree); |
---|
701 | #endif |
---|
702 | } |
---|
703 | |
---|
704 | end_char0: |
---|
705 | if ( on_rational ) |
---|
706 | On(SW_RATIONAL); |
---|
707 | else |
---|
708 | Off(SW_RATIONAL); |
---|
709 | if ( ! cd.isOne() ) |
---|
710 | { |
---|
711 | CFFactor new_first( F.getFirst().factor() / cd ); |
---|
712 | F.removeFirst(); |
---|
713 | F.insert( new_first ); |
---|
714 | } |
---|
715 | } |
---|
716 | |
---|
717 | if(isOn(SW_USE_NTL_SORT)) F.sort(cmpCF); |
---|
718 | return F; |
---|
719 | } |
---|
720 | |
---|
721 | /** |
---|
722 | * factorization over \f$ F_p(\alpha) \f$ or \f$ Q(\alpha) \f$ |
---|
723 | **/ |
---|
724 | CFFList factorize ( const CanonicalForm & f, const Variable & alpha ) |
---|
725 | { |
---|
726 | if ( f.inCoeffDomain() ) |
---|
727 | return CFFList( f ); |
---|
728 | //out_cf("factorize:",f,"==================================\n"); |
---|
729 | //out_cf("mipo:",getMipo(alpha),"\n"); |
---|
730 | |
---|
731 | CFFList F; |
---|
732 | ASSERT( alpha.level() < 0 && getReduce (alpha), "not an algebraic extension" ); |
---|
733 | #ifndef NOASSERT |
---|
734 | Variable beta; |
---|
735 | if (hasFirstAlgVar(f, beta)) |
---|
736 | ASSERT (beta == alpha, "f has an algebraic variable that \ |
---|
737 | does not coincide with alpha"); |
---|
738 | #endif |
---|
739 | int ch=getCharacteristic(); |
---|
740 | if (ch>0) |
---|
741 | { |
---|
742 | if (f.isUnivariate()) |
---|
743 | { |
---|
744 | #ifdef HAVE_NTL |
---|
745 | if (/*getCharacteristic()*/ch==2) |
---|
746 | { |
---|
747 | // special case : GF2 |
---|
748 | |
---|
749 | // remainder is two ==> nothing to do |
---|
750 | |
---|
751 | // set minimal polynomial in NTL using the optimized conversion routines for characteristic 2 |
---|
752 | GF2X minPo=convertFacCF2NTLGF2X(getMipo(alpha,f.mvar())); |
---|
753 | GF2E::init (minPo); |
---|
754 | |
---|
755 | // convert to NTL again using the faster conversion routines |
---|
756 | GF2EX f1; |
---|
757 | if (isPurePoly(f)) |
---|
758 | { |
---|
759 | GF2X f_tmp=convertFacCF2NTLGF2X(f); |
---|
760 | f1=to_GF2EX(f_tmp); |
---|
761 | } |
---|
762 | else |
---|
763 | f1=convertFacCF2NTLGF2EX(f,minPo); |
---|
764 | |
---|
765 | // make monic (in Z/2(a)) |
---|
766 | GF2E f1_coef=LeadCoeff(f1); |
---|
767 | MakeMonic(f1); |
---|
768 | |
---|
769 | // factorize using NTL |
---|
770 | vec_pair_GF2EX_long factors; |
---|
771 | CanZass(factors,f1); |
---|
772 | |
---|
773 | // return converted result |
---|
774 | F=convertNTLvec_pair_GF2EX_long2FacCFFList(factors,f1_coef,f.mvar(),alpha); |
---|
775 | if(isOn(SW_USE_NTL_SORT)) F.sort(cmpCF); |
---|
776 | return F; |
---|
777 | } |
---|
778 | #endif |
---|
779 | #if (HAVE_FLINT && __FLINT_RELEASE >= 20400) |
---|
780 | { |
---|
781 | // use FLINT |
---|
782 | nmod_poly_t FLINTmipo, leadingCoeff; |
---|
783 | fq_nmod_ctx_t fq_con; |
---|
784 | |
---|
785 | nmod_poly_init (FLINTmipo, ch); |
---|
786 | nmod_poly_init (leadingCoeff, ch); |
---|
787 | convertFacCF2nmod_poly_t (FLINTmipo, getMipo (alpha)); |
---|
788 | |
---|
789 | fq_nmod_ctx_init_modulus (fq_con, FLINTmipo, "Z"); |
---|
790 | fq_nmod_poly_t FLINTF; |
---|
791 | convertFacCF2Fq_nmod_poly_t (FLINTF, f, fq_con); |
---|
792 | fq_nmod_poly_factor_t res; |
---|
793 | fq_nmod_poly_factor_init (res, fq_con); |
---|
794 | fq_nmod_poly_factor (res, leadingCoeff, FLINTF, fq_con); |
---|
795 | F= convertFLINTFq_nmod_poly_factor2FacCFFList (res, f.mvar(), alpha, fq_con); |
---|
796 | F.insert (CFFactor (Lc (f), 1)); |
---|
797 | |
---|
798 | fq_nmod_poly_factor_clear (res, fq_con); |
---|
799 | fq_nmod_poly_clear (FLINTF, fq_con); |
---|
800 | nmod_poly_clear (FLINTmipo); |
---|
801 | nmod_poly_clear (leadingCoeff); |
---|
802 | fq_nmod_ctx_clear (fq_con); |
---|
803 | if(isOn(SW_USE_NTL_SORT)) F.sort(cmpCF); |
---|
804 | return F; |
---|
805 | } |
---|
806 | #endif |
---|
807 | #ifdef HAVE_NTL |
---|
808 | { |
---|
809 | // use NTL |
---|
810 | if (fac_NTL_char != ch) |
---|
811 | { |
---|
812 | fac_NTL_char = ch; |
---|
813 | zz_p::init(ch); |
---|
814 | } |
---|
815 | |
---|
816 | // set minimal polynomial in NTL |
---|
817 | zz_pX minPo=convertFacCF2NTLzzpX(getMipo(alpha)); |
---|
818 | zz_pE::init (minPo); |
---|
819 | |
---|
820 | // convert to NTL |
---|
821 | zz_pEX f1=convertFacCF2NTLzz_pEX(f,minPo); |
---|
822 | zz_pE leadcoeff= LeadCoeff(f1); |
---|
823 | |
---|
824 | //make monic |
---|
825 | f1=f1 / leadcoeff; //leadcoeff==LeadCoeff(f1); |
---|
826 | |
---|
827 | // factorize |
---|
828 | vec_pair_zz_pEX_long factors; |
---|
829 | CanZass(factors,f1); |
---|
830 | |
---|
831 | // return converted result |
---|
832 | F=convertNTLvec_pair_zzpEX_long2FacCFFList(factors,leadcoeff,f.mvar(),alpha); |
---|
833 | //test_cff(F,f); |
---|
834 | if(isOn(SW_USE_NTL_SORT)) F.sort(cmpCF); |
---|
835 | return F; |
---|
836 | } |
---|
837 | #endif |
---|
838 | #if !defined(HAVE_NTL) && !defined(HAVE_FLINT) |
---|
839 | // char p, extension, univariate |
---|
840 | CanonicalForm c=Lc(f); |
---|
841 | CanonicalForm fc=f/c; |
---|
842 | F=FpFactorizeUnivariateCZ( fc, false, 1, alpha, Variable() ); |
---|
843 | F.insert (CFFactor (c, 1)); |
---|
844 | #endif |
---|
845 | } |
---|
846 | else // char p, multivariate |
---|
847 | { |
---|
848 | #ifdef HAVE_NTL |
---|
849 | F= FqFactorize (f, alpha); |
---|
850 | #else |
---|
851 | factoryError ("univariate factorization depends on NTL(missing)"); |
---|
852 | return CFFList (CFFactor (f, 1)); |
---|
853 | #endif |
---|
854 | } |
---|
855 | } |
---|
856 | else // Q(a)[x] |
---|
857 | { |
---|
858 | if (f.isUnivariate()) |
---|
859 | { |
---|
860 | F= AlgExtFactorize (f, alpha); |
---|
861 | } |
---|
862 | else //Q(a)[x1,...,xn] |
---|
863 | { |
---|
864 | #ifdef HAVE_NTL |
---|
865 | F= ratFactorize (f, alpha); |
---|
866 | #else |
---|
867 | factoryError ("multivariate factorization depends on NTL(missing)"); |
---|
868 | return CFFList (CFFactor (f, 1)); |
---|
869 | #endif |
---|
870 | } |
---|
871 | } |
---|
872 | if(isOn(SW_USE_NTL_SORT)) F.sort(cmpCF); |
---|
873 | return F; |
---|
874 | } |
---|
875 | |
---|
876 | /** |
---|
877 | * squarefree factorization |
---|
878 | **/ |
---|
879 | CFFList sqrFree ( const CanonicalForm & f, bool sort ) |
---|
880 | { |
---|
881 | // ASSERT( f.isUnivariate(), "multivariate factorization not implemented" ); |
---|
882 | CFFList result; |
---|
883 | |
---|
884 | if ( getCharacteristic() == 0 ) |
---|
885 | result = sqrFreeZ( f ); |
---|
886 | else |
---|
887 | { |
---|
888 | Variable alpha; |
---|
889 | if (hasFirstAlgVar (f, alpha)) |
---|
890 | result = FqSqrf( f, alpha ); |
---|
891 | else |
---|
892 | result= FpSqrf (f); |
---|
893 | } |
---|
894 | if (sort) |
---|
895 | { |
---|
896 | CFFactor buf= result.getFirst(); |
---|
897 | result.removeFirst(); |
---|
898 | result= sortCFFList (result); |
---|
899 | result.insert (buf); |
---|
900 | } |
---|
901 | return result; |
---|
902 | } |
---|
903 | |
---|