1 | /**************************************** |
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2 | * Computer Algebra System SINGULAR * |
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3 | ****************************************/ |
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4 | /* $Id$ */ |
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5 | /* |
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6 | * ABSTRACT: numbers modulo n |
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7 | */ |
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8 | |
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9 | #include "config.h" |
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10 | #include <misc/auxiliary.h> |
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11 | |
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12 | #ifdef HAVE_RINGS |
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13 | |
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14 | #include <misc/mylimits.h> |
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15 | #include <coeffs/coeffs.h> |
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16 | #include <reporter/reporter.h> |
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17 | #include <omalloc/omalloc.h> |
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18 | #include <coeffs/numbers.h> |
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19 | #include <coeffs/longrat.h> |
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20 | #include <coeffs/mpr_complex.h> |
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21 | #include <coeffs/rmodulon.h> |
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22 | #include "si_gmp.h" |
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23 | |
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24 | #include <string.h> |
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25 | |
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26 | extern omBin gmp_nrz_bin; |
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27 | |
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28 | void nrnCoeffWrite (const coeffs r) |
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29 | { |
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30 | long l = (long)mpz_sizeinbase(r->modBase, 10) + 2; |
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31 | char* s = (char*) omAlloc(l); |
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32 | if (nCoeff_is_Ring_ModN(r)) Print("// Z/%s\n", s); |
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33 | else if (nCoeff_is_Ring_PtoM(r)) Print("// Z/%s^%lu\n", s, r->modExponent); |
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34 | omFreeSize((ADDRESS)s, l); |
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35 | } |
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36 | |
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37 | static BOOLEAN nrnCoeffsEqual(const coeffs r, n_coeffType n, void * parameter) |
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38 | { |
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39 | /* test, if r is an instance of nInitCoeffs(n,parameter) */ |
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40 | return (n==n_Zn) && (mpz_cmp(r->modNumber,(mpz_ptr)parameter)==0); |
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41 | } |
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42 | |
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43 | |
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44 | /* for initializing function pointers */ |
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45 | BOOLEAN nrnInitChar (coeffs r, void* p) |
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46 | { |
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47 | |
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48 | nrnInitExp((int)(long)(p), r); |
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49 | r->ringtype = 2; |
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50 | r->type = n_Zn; |
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51 | |
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52 | r->cfInit = nrnInit; |
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53 | r->cfDelete = nrnDelete; |
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54 | r->cfCopy = nrnCopy; |
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55 | r->cfSize = nrnSize; |
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56 | r->cfInt = nrnInt; |
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57 | r->cfAdd = nrnAdd; |
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58 | r->cfSub = nrnSub; |
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59 | r->cfMult = nrnMult; |
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60 | r->cfDiv = nrnDiv; |
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61 | r->cfIntDiv = nrnIntDiv; |
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62 | r->cfIntMod = nrnMod; |
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63 | r->cfExactDiv = nrnDiv; |
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64 | r->cfNeg = nrnNeg; |
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65 | r->cfInvers = nrnInvers; |
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66 | r->cfDivBy = nrnDivBy; |
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67 | r->cfDivComp = nrnDivComp; |
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68 | r->cfGreater = nrnGreater; |
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69 | r->cfEqual = nrnEqual; |
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70 | r->cfIsZero = nrnIsZero; |
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71 | r->cfIsOne = nrnIsOne; |
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72 | r->cfIsMOne = nrnIsMOne; |
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73 | r->cfGreaterZero = nrnGreaterZero; |
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74 | r->cfWrite = nrnWrite; |
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75 | r->cfRead = nrnRead; |
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76 | r->cfPower = nrnPower; |
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77 | r->cfSetMap = nrnSetMap; |
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78 | r->cfNormalize = ndNormalize; |
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79 | r->cfLcm = nrnLcm; |
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80 | r->cfGcd = nrnGcd; |
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81 | r->cfIsUnit = nrnIsUnit; |
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82 | r->cfGetUnit = nrnGetUnit; |
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83 | r->cfExtGcd = nrnExtGcd; |
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84 | r->cfName = ndName; |
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85 | r->cfCoeffWrite = nrnCoeffWrite; |
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86 | r->nCoeffIsEqual = nrnCoeffsEqual; |
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87 | #ifdef LDEBUG |
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88 | r->cfDBTest = nrnDBTest; |
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89 | #endif |
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90 | return FALSE; |
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91 | } |
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92 | |
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93 | /* |
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94 | * create a number from int |
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95 | */ |
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96 | number nrnInit(int i, const coeffs r) |
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97 | { |
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98 | int_number erg = (int_number) omAllocBin(gmp_nrz_bin); |
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99 | mpz_init_set_si(erg, i); |
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100 | mpz_mod(erg, erg, r->modNumber); |
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101 | return (number) erg; |
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102 | } |
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103 | |
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104 | void nrnDelete(number *a, const coeffs r) |
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105 | { |
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106 | if (*a == NULL) return; |
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107 | mpz_clear((int_number) *a); |
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108 | omFreeBin((void *) *a, gmp_nrz_bin); |
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109 | *a = NULL; |
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110 | } |
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111 | |
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112 | number nrnCopy(number a, const coeffs r) |
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113 | { |
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114 | int_number erg = (int_number) omAllocBin(gmp_nrz_bin); |
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115 | mpz_init_set(erg, (int_number) a); |
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116 | return (number) erg; |
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117 | } |
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118 | |
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119 | int nrnSize(number a, const coeffs r) |
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120 | { |
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121 | if (a == NULL) return 0; |
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122 | return sizeof(mpz_t); |
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123 | } |
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124 | |
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125 | /* |
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126 | * convert a number to int |
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127 | */ |
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128 | int nrnInt(number &n, const coeffs r) |
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129 | { |
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130 | return (int)mpz_get_si((int_number) n); |
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131 | } |
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132 | |
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133 | /* |
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134 | * Multiply two numbers |
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135 | */ |
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136 | number nrnMult(number a, number b, const coeffs r) |
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137 | { |
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138 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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139 | mpz_init(erg); |
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140 | mpz_mul(erg, (int_number)a, (int_number) b); |
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141 | mpz_mod(erg, erg, r->modNumber); |
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142 | return (number) erg; |
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143 | } |
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144 | |
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145 | void nrnPower(number a, int i, number * result, const coeffs r) |
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146 | { |
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147 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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148 | mpz_init(erg); |
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149 | mpz_powm_ui(erg, (int_number)a, i, r->modNumber); |
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150 | *result = (number) erg; |
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151 | } |
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152 | |
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153 | number nrnAdd(number a, number b, const coeffs r) |
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154 | { |
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155 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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156 | mpz_init(erg); |
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157 | mpz_add(erg, (int_number)a, (int_number) b); |
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158 | mpz_mod(erg, erg, r->modNumber); |
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159 | return (number) erg; |
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160 | } |
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161 | |
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162 | number nrnSub(number a, number b, const coeffs r) |
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163 | { |
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164 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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165 | mpz_init(erg); |
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166 | mpz_sub(erg, (int_number)a, (int_number) b); |
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167 | mpz_mod(erg, erg, r->modNumber); |
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168 | return (number) erg; |
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169 | } |
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170 | |
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171 | number nrnNeg(number c, const coeffs r) |
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172 | { |
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173 | if( !nrnIsZero(c, r) ) |
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174 | // Attention: This method operates in-place. |
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175 | mpz_sub((int_number)c, r->modNumber, (int_number)c); |
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176 | return c; |
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177 | } |
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178 | |
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179 | number nrnInvers(number c, const coeffs r) |
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180 | { |
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181 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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182 | mpz_init(erg); |
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183 | mpz_invert(erg, (int_number)c, r->modNumber); |
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184 | return (number) erg; |
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185 | } |
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186 | |
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187 | /* |
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188 | * Give the smallest k, such that a * x = k = b * y has a solution |
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189 | * TODO: lcm(gcd,gcd) better than gcd(lcm) ? |
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190 | */ |
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191 | number nrnLcm(number a, number b, const coeffs r) |
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192 | { |
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193 | number erg = nrnGcd(NULL, a, r); |
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194 | number tmp = nrnGcd(NULL, b, r); |
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195 | mpz_lcm((int_number)erg, (int_number)erg, (int_number)tmp); |
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196 | nrnDelete(&tmp, NULL); |
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197 | return (number)erg; |
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198 | } |
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199 | |
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200 | /* |
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201 | * Give the largest k, such that a = x * k, b = y * k has |
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202 | * a solution. |
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203 | */ |
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204 | number nrnGcd(number a, number b, const coeffs r) |
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205 | { |
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206 | if ((a == NULL) && (b == NULL)) return nrnInit(0,r); |
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207 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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208 | mpz_init_set(erg, r->modNumber); |
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209 | if (a != NULL) mpz_gcd(erg, erg, (int_number)a); |
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210 | if (b != NULL) mpz_gcd(erg, erg, (int_number)b); |
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211 | return (number)erg; |
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212 | } |
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213 | |
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214 | /* Not needed any more, but may have room for improvement |
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215 | number nrnGcd3(number a,number b, number c,ring r) |
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216 | { |
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217 | int_number erg = (int_number) omAllocBin(gmp_nrz_bin); |
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218 | mpz_init(erg); |
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219 | if (a == NULL) a = (number)r->modNumber; |
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220 | if (b == NULL) b = (number)r->modNumber; |
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221 | if (c == NULL) c = (number)r->modNumber; |
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222 | mpz_gcd(erg, (int_number)a, (int_number)b); |
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223 | mpz_gcd(erg, erg, (int_number)c); |
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224 | mpz_gcd(erg, erg, r->modNumber); |
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225 | return (number)erg; |
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226 | } |
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227 | */ |
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228 | |
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229 | /* |
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230 | * Give the largest k, such that a = x * k, b = y * k has |
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231 | * a solution and r, s, s.t. k = s*a + t*b |
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232 | */ |
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233 | number nrnExtGcd(number a, number b, number *s, number *t, const coeffs r) |
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234 | { |
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235 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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236 | int_number bs = (int_number)omAllocBin(gmp_nrz_bin); |
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237 | int_number bt = (int_number)omAllocBin(gmp_nrz_bin); |
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238 | mpz_init(erg); |
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239 | mpz_init(bs); |
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240 | mpz_init(bt); |
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241 | mpz_gcdext(erg, bs, bt, (int_number)a, (int_number)b); |
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242 | mpz_mod(bs, bs, r->modNumber); |
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243 | mpz_mod(bt, bt, r->modNumber); |
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244 | *s = (number)bs; |
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245 | *t = (number)bt; |
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246 | return (number)erg; |
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247 | } |
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248 | |
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249 | BOOLEAN nrnIsZero(number a, const coeffs r) |
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250 | { |
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251 | #ifdef LDEBUG |
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252 | if (a == NULL) return FALSE; |
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253 | #endif |
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254 | return 0 == mpz_cmpabs_ui((int_number)a, 0); |
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255 | } |
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256 | |
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257 | BOOLEAN nrnIsOne(number a, const coeffs r) |
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258 | { |
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259 | #ifdef LDEBUG |
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260 | if (a == NULL) return FALSE; |
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261 | #endif |
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262 | return 0 == mpz_cmp_si((int_number)a, 1); |
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263 | } |
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264 | |
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265 | BOOLEAN nrnIsMOne(number a, const coeffs r) |
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266 | { |
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267 | #ifdef LDEBUG |
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268 | if (a == NULL) return FALSE; |
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269 | #endif |
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270 | mpz_t t; mpz_init_set(t, (int_number)a); |
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271 | mpz_add_ui(t, t, 1); |
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272 | bool erg = (0 == mpz_cmp(t, r->modNumber)); |
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273 | mpz_clear(t); |
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274 | return erg; |
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275 | } |
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276 | |
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277 | BOOLEAN nrnEqual(number a, number b, const coeffs r) |
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278 | { |
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279 | return 0 == mpz_cmp((int_number)a, (int_number)b); |
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280 | } |
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281 | |
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282 | BOOLEAN nrnGreater(number a, number b, const coeffs r) |
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283 | { |
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284 | return 0 < mpz_cmp((int_number)a, (int_number)b); |
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285 | } |
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286 | |
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287 | BOOLEAN nrnGreaterZero(number k, const coeffs r) |
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288 | { |
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289 | return 0 < mpz_cmp_si((int_number)k, 0); |
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290 | } |
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291 | |
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292 | BOOLEAN nrnIsUnit(number a, const coeffs r) |
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293 | { |
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294 | number tmp = nrnGcd(a, (number)r->modNumber, r); |
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295 | bool res = nrnIsOne(tmp, r); |
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296 | nrnDelete(&tmp, NULL); |
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297 | return res; |
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298 | } |
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299 | |
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300 | number nrnGetUnit(number k, const coeffs r) |
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301 | { |
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302 | if (mpz_divisible_p(r->modNumber, (int_number)k)) return nrnInit(1,r); |
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303 | |
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304 | int_number unit = (int_number)nrnGcd(k, 0, r); |
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305 | mpz_tdiv_q(unit, (int_number)k, unit); |
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306 | int_number gcd = (int_number)nrnGcd((number)unit, 0, r); |
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307 | if (!nrnIsOne((number)gcd,r)) |
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308 | { |
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309 | int_number ctmp; |
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310 | // tmp := unit^2 |
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311 | int_number tmp = (int_number) nrnMult((number) unit,(number) unit,r); |
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312 | // gcd_new := gcd(tmp, 0) |
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313 | int_number gcd_new = (int_number) nrnGcd((number) tmp, 0, r); |
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314 | while (!nrnEqual((number) gcd_new,(number) gcd,r)) |
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315 | { |
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316 | // gcd := gcd_new |
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317 | ctmp = gcd; |
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318 | gcd = gcd_new; |
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319 | gcd_new = ctmp; |
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320 | // tmp := tmp * unit |
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321 | mpz_mul(tmp, tmp, unit); |
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322 | mpz_mod(tmp, tmp, r->modNumber); |
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323 | // gcd_new := gcd(tmp, 0) |
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324 | mpz_gcd(gcd_new, tmp, r->modNumber); |
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325 | } |
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326 | // unit := unit + modNumber / gcd_new |
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327 | mpz_tdiv_q(tmp, r->modNumber, gcd_new); |
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328 | mpz_add(unit, unit, tmp); |
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329 | mpz_mod(unit, unit, r->modNumber); |
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330 | nrnDelete((number*) &gcd_new, NULL); |
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331 | nrnDelete((number*) &tmp, NULL); |
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332 | } |
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333 | nrnDelete((number*) &gcd, NULL); |
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334 | return (number)unit; |
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335 | } |
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336 | |
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337 | BOOLEAN nrnDivBy(number a, number b, const coeffs r) |
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338 | { |
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339 | if (a == NULL) |
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340 | return mpz_divisible_p(r->modNumber, (int_number)b); |
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341 | else |
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342 | { /* b divides a iff b/gcd(a, b) is a unit in the given ring: */ |
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343 | number n = nrnGcd(a, b, r); |
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344 | mpz_tdiv_q((int_number)n, (int_number)b, (int_number)n); |
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345 | bool result = nrnIsUnit(n, r); |
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346 | nrnDelete(&n, NULL); |
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347 | return result; |
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348 | } |
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349 | } |
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350 | |
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351 | int nrnDivComp(number a, number b, const coeffs r) |
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352 | { |
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353 | if (nrnEqual(a, b,r)) return 2; |
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354 | if (mpz_divisible_p((int_number) a, (int_number) b)) return -1; |
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355 | if (mpz_divisible_p((int_number) b, (int_number) a)) return 1; |
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356 | return 0; |
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357 | } |
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358 | |
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359 | number nrnDiv(number a, number b, const coeffs r) |
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360 | { |
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361 | if (a == NULL) a = (number)r->modNumber; |
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362 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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363 | mpz_init(erg); |
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364 | if (mpz_divisible_p((int_number)a, (int_number)b)) |
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365 | { |
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366 | mpz_divexact(erg, (int_number)a, (int_number)b); |
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367 | return (number)erg; |
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368 | } |
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369 | else |
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370 | { |
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371 | int_number gcd = (int_number)nrnGcd(a, b, r); |
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372 | mpz_divexact(erg, (int_number)b, gcd); |
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373 | if (!nrnIsUnit((number)erg, r)) |
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374 | { |
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375 | WerrorS("Division not possible, even by cancelling zero divisors."); |
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376 | WerrorS("Result is integer division without remainder."); |
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377 | mpz_tdiv_q(erg, (int_number) a, (int_number) b); |
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378 | nrnDelete((number*) &gcd, NULL); |
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379 | return (number)erg; |
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380 | } |
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381 | // a / gcd(a,b) * [b / gcd (a,b)]^(-1) |
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382 | int_number tmp = (int_number)nrnInvers((number) erg,r); |
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383 | mpz_divexact(erg, (int_number)a, gcd); |
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384 | mpz_mul(erg, erg, tmp); |
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385 | nrnDelete((number*) &gcd, NULL); |
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386 | nrnDelete((number*) &tmp, NULL); |
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387 | mpz_mod(erg, erg, r->modNumber); |
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388 | return (number)erg; |
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389 | } |
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390 | } |
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391 | |
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392 | number nrnMod(number a, number b, const coeffs r) |
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393 | { |
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394 | /* |
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395 | We need to return the number rr which is uniquely determined by the |
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396 | following two properties: |
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397 | (1) 0 <= rr < |b| (with respect to '<' and '<=' performed in Z x Z) |
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398 | (2) There exists some k in the integers Z such that a = k * b + rr. |
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399 | Consider g := gcd(n, |b|). Note that then |b|/g is a unit in Z/n. |
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400 | Now, there are three cases: |
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401 | (a) g = 1 |
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402 | Then |b| is a unit in Z/n, i.e. |b| (and also b) divides a. |
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403 | Thus rr = 0. |
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404 | (b) g <> 1 and g divides a |
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405 | Then a = (a/g) * (|b|/g)^(-1) * b (up to sign), i.e. again rr = 0. |
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406 | (c) g <> 1 and g does not divide a |
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407 | Then denote the division with remainder of a by g as this: |
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408 | a = s * g + t. Then t = a - s * g = a - s * (|b|/g)^(-1) * |b| |
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409 | fulfills (1) and (2), i.e. rr := t is the correct result. Hence |
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410 | in this third case, rr is the remainder of division of a by g in Z. |
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411 | Remark: according to mpz_mod: a,b are always non-negative |
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412 | */ |
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413 | int_number g = (int_number)omAllocBin(gmp_nrz_bin); |
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414 | int_number rr = (int_number)omAllocBin(gmp_nrz_bin); |
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415 | mpz_init(g); |
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416 | mpz_init_set_si(rr, 0); |
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417 | mpz_gcd(g, (int_number)r->modNumber, (int_number)b); // g is now as above |
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418 | if (mpz_cmp_si(g, (long)1) != 0) mpz_mod(rr, (int_number)a, g); // the case g <> 1 |
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419 | mpz_clear(g); |
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420 | omFreeBin(g, gmp_nrz_bin); |
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421 | return (number)rr; |
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422 | } |
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423 | |
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424 | number nrnIntDiv(number a, number b, const coeffs r) |
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425 | { |
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426 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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427 | mpz_init(erg); |
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428 | if (a == NULL) a = (number)r->modNumber; |
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429 | mpz_tdiv_q(erg, (int_number)a, (int_number)b); |
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430 | return (number)erg; |
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431 | } |
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432 | |
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433 | /* |
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434 | * Helper function for computing the module |
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435 | */ |
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436 | |
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437 | int_number nrnMapCoef = NULL; |
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438 | |
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439 | number nrnMapModN(number from, const coeffs src, const coeffs dst) |
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440 | { |
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441 | return nrnMult(from, (number) nrnMapCoef, dst); |
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442 | } |
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443 | |
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444 | number nrnMap2toM(number from, const coeffs src, const coeffs dst) |
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445 | { |
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446 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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447 | mpz_init(erg); |
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448 | mpz_mul_ui(erg, nrnMapCoef, (NATNUMBER)from); |
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449 | mpz_mod(erg, erg, dst->modNumber); |
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450 | return (number)erg; |
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451 | } |
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452 | |
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453 | number nrnMapZp(number from, const coeffs src, const coeffs dst) |
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454 | { |
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455 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
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456 | mpz_init(erg); |
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457 | // TODO: use npInt(...) |
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458 | mpz_mul_si(erg, nrnMapCoef, (NATNUMBER)from); |
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459 | mpz_mod(erg, erg, dst->modNumber); |
---|
460 | return (number)erg; |
---|
461 | } |
---|
462 | |
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463 | number nrnMapGMP(number from, const coeffs src, const coeffs dst) |
---|
464 | { |
---|
465 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
---|
466 | mpz_init(erg); |
---|
467 | mpz_mod(erg, (int_number)from, dst->modNumber); |
---|
468 | return (number)erg; |
---|
469 | } |
---|
470 | |
---|
471 | number nrnMapQ(number from, const coeffs src, const coeffs dst) |
---|
472 | { |
---|
473 | int_number erg = (int_number)omAllocBin(gmp_nrz_bin); |
---|
474 | mpz_init(erg); |
---|
475 | nlGMP(from, (number)erg, src); |
---|
476 | mpz_mod(erg, erg, src->modNumber); |
---|
477 | return (number)erg; |
---|
478 | } |
---|
479 | |
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480 | nMapFunc nrnSetMap(const coeffs src, const coeffs dst) |
---|
481 | { |
---|
482 | /* dst = currRing->cf */ |
---|
483 | if (nCoeff_is_Ring_Z(src)) |
---|
484 | { |
---|
485 | return nrnMapGMP; |
---|
486 | } |
---|
487 | if (nCoeff_is_Q(src)) |
---|
488 | { |
---|
489 | return nrnMapQ; |
---|
490 | } |
---|
491 | // Some type of Z/n ring / field |
---|
492 | if (nCoeff_is_Ring_ModN(src) || nCoeff_is_Ring_PtoM(src) || |
---|
493 | nCoeff_is_Ring_2toM(src) || nCoeff_is_Zp(src)) |
---|
494 | { |
---|
495 | if ( (src->ringtype > 0) |
---|
496 | && (mpz_cmp(src->modBase, dst->modBase) == 0) |
---|
497 | && (src->modExponent == dst->modExponent)) return nrnMapGMP; |
---|
498 | else |
---|
499 | { |
---|
500 | int_number nrnMapModul = (int_number) omAllocBin(gmp_nrz_bin); |
---|
501 | // Computing the n of Z/n |
---|
502 | if (nCoeff_is_Zp(src)) |
---|
503 | { |
---|
504 | mpz_init_set_si(nrnMapModul, src->ch); |
---|
505 | } |
---|
506 | else |
---|
507 | { |
---|
508 | mpz_init(nrnMapModul); |
---|
509 | mpz_set(nrnMapModul, src->modNumber); |
---|
510 | } |
---|
511 | // nrnMapCoef = 1 in dst if dst is a subring of src |
---|
512 | // nrnMapCoef = 0 in dst / src if src is a subring of dst |
---|
513 | if (nrnMapCoef == NULL) |
---|
514 | { |
---|
515 | nrnMapCoef = (int_number) omAllocBin(gmp_nrz_bin); |
---|
516 | mpz_init(nrnMapCoef); |
---|
517 | } |
---|
518 | if (mpz_divisible_p(nrnMapModul, dst->modNumber)) |
---|
519 | { |
---|
520 | mpz_set_si(nrnMapCoef, 1); |
---|
521 | } |
---|
522 | else |
---|
523 | if (nrnDivBy(NULL, (number) nrnMapModul,dst)) |
---|
524 | { |
---|
525 | mpz_divexact(nrnMapCoef, dst->modNumber, nrnMapModul); |
---|
526 | int_number tmp = dst->modNumber; |
---|
527 | dst->modNumber = nrnMapModul; |
---|
528 | if (!nrnIsUnit((number) nrnMapCoef,dst)) |
---|
529 | { |
---|
530 | dst->modNumber = tmp; |
---|
531 | nrnDelete((number*) &nrnMapModul, dst); |
---|
532 | return NULL; |
---|
533 | } |
---|
534 | int_number inv = (int_number) nrnInvers((number) nrnMapCoef,dst); |
---|
535 | dst->modNumber = tmp; |
---|
536 | mpz_mul(nrnMapCoef, nrnMapCoef, inv); |
---|
537 | mpz_mod(nrnMapCoef, nrnMapCoef, dst->modNumber); |
---|
538 | nrnDelete((number*) &inv, dst); |
---|
539 | } |
---|
540 | else |
---|
541 | { |
---|
542 | nrnDelete((number*) &nrnMapModul, dst); |
---|
543 | return NULL; |
---|
544 | } |
---|
545 | nrnDelete((number*) &nrnMapModul, dst); |
---|
546 | if (nCoeff_is_Ring_2toM(src)) |
---|
547 | return nrnMap2toM; |
---|
548 | else if (nCoeff_is_Zp(src)) |
---|
549 | return nrnMapZp; |
---|
550 | else |
---|
551 | return nrnMapModN; |
---|
552 | } |
---|
553 | } |
---|
554 | return NULL; // default |
---|
555 | } |
---|
556 | |
---|
557 | /* |
---|
558 | * set the exponent (allocate and init tables) (TODO) |
---|
559 | */ |
---|
560 | |
---|
561 | void nrnSetExp(int m, coeffs r) |
---|
562 | { |
---|
563 | /* clean up former stuff */ |
---|
564 | if (r->modBase != NULL) mpz_clear(r->modBase); |
---|
565 | if (r->modNumber != NULL) mpz_clear(r->modNumber); |
---|
566 | |
---|
567 | /* this is Z/m = Z/(m^1), hence set modBase = m, modExponent = 1: */ |
---|
568 | r->modBase = (int_number)omAllocBin(gmp_nrz_bin); |
---|
569 | mpz_init(r->modBase); |
---|
570 | mpz_set_ui(r->modBase, (unsigned long)m); |
---|
571 | r->modExponent = 1; |
---|
572 | r->modNumber = (int_number)omAllocBin(gmp_nrz_bin); |
---|
573 | mpz_init(r->modNumber); |
---|
574 | mpz_set(r->modNumber, r->modBase); |
---|
575 | /* mpz_pow_ui(r->modNumber, r->modNumber, r->modExponent); */ |
---|
576 | } |
---|
577 | |
---|
578 | /* We expect this ring to be Z/m for some m > 2 which is not a prime. */ |
---|
579 | void nrnInitExp(int m, coeffs r) |
---|
580 | { |
---|
581 | if (m <= 2) WarnS("nrnInitExp failed (m in Z/m too small)"); |
---|
582 | nrnSetExp(m, r); |
---|
583 | } |
---|
584 | |
---|
585 | #ifdef LDEBUG |
---|
586 | BOOLEAN nrnDBTest (number a, const char *f, const int l, const coeffs r) |
---|
587 | { |
---|
588 | if (a==NULL) return TRUE; |
---|
589 | if ( (mpz_cmp_si((int_number) a, 0) < 0) || (mpz_cmp((int_number) a, r->modNumber) > 0) ) |
---|
590 | { |
---|
591 | return FALSE; |
---|
592 | } |
---|
593 | return TRUE; |
---|
594 | } |
---|
595 | #endif |
---|
596 | |
---|
597 | /*2 |
---|
598 | * extracts a long integer from s, returns the rest (COPY FROM longrat0.cc) |
---|
599 | */ |
---|
600 | static const char * nlCPEatLongC(char *s, mpz_ptr i) |
---|
601 | { |
---|
602 | const char * start=s; |
---|
603 | if (!(*s >= '0' && *s <= '9')) |
---|
604 | { |
---|
605 | mpz_init_set_si(i, 1); |
---|
606 | return s; |
---|
607 | } |
---|
608 | mpz_init(i); |
---|
609 | while (*s >= '0' && *s <= '9') s++; |
---|
610 | if (*s=='\0') |
---|
611 | { |
---|
612 | mpz_set_str(i,start,10); |
---|
613 | } |
---|
614 | else |
---|
615 | { |
---|
616 | char c=*s; |
---|
617 | *s='\0'; |
---|
618 | mpz_set_str(i,start,10); |
---|
619 | *s=c; |
---|
620 | } |
---|
621 | return s; |
---|
622 | } |
---|
623 | |
---|
624 | const char * nrnRead (const char *s, number *a, const coeffs r) |
---|
625 | { |
---|
626 | int_number z = (int_number) omAllocBin(gmp_nrz_bin); |
---|
627 | { |
---|
628 | s = nlCPEatLongC((char *)s, z); |
---|
629 | } |
---|
630 | mpz_mod(z, z, r->modNumber); |
---|
631 | *a = (number) z; |
---|
632 | return s; |
---|
633 | } |
---|
634 | #endif |
---|
635 | /* #ifdef HAVE_RINGS */ |
---|