1 | // binomial.cc |
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2 | |
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3 | // implementation of class binomial |
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4 | |
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5 | #ifndef BINOMIAL_CC |
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6 | #define BINOMIAL_CC |
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7 | |
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8 | #include <climits> |
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9 | #include "binomial__term_ordering.h" |
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10 | |
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11 | ///////////////////////// constructors and destructor ////////////////////// |
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12 | |
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13 | // For a better overview, the constructor code is separated for |
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14 | // NO_SUPPORT_DRIVEN_METHODS and SUPPORT_DRIVEN_METHODS. |
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15 | |
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16 | #ifdef NO_SUPPORT_DRIVEN_METHODS |
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17 | |
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18 | binomial::binomial(const short& number_of_variables) |
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19 | :_number_of_variables(number_of_variables) |
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20 | { |
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21 | exponent_vector=new Integer[_number_of_variables]; |
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22 | } |
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23 | |
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24 | |
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25 | |
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26 | |
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27 | binomial::binomial(const short& number_of_variables,const Integer* exponents) |
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28 | :_number_of_variables(number_of_variables) |
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29 | { |
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30 | |
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31 | // range check for rarely used constructors |
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32 | if(_number_of_variables<=0) |
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33 | { |
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34 | cerr<<"\nWARNING: binomial::binomial(const short&, const Integer*):\n" |
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35 | "argument out of range"<<endl; |
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36 | exponent_vector=NULL; |
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37 | // to avoid problems when deleting |
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38 | return; |
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39 | } |
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40 | |
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41 | // initialization |
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42 | exponent_vector=new Integer[_number_of_variables]; |
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43 | for(short i=0;i<_number_of_variables;i++) |
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44 | exponent_vector[i]=exponents[i]; |
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45 | } |
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46 | |
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47 | |
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48 | |
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49 | |
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50 | binomial::binomial(const short& number_of_variables,const Integer* exponents, |
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51 | const term_ordering& w) |
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52 | :_number_of_variables(number_of_variables) |
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53 | { |
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54 | |
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55 | // range check for rarely used constructors |
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56 | if(_number_of_variables<=0) |
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57 | { |
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58 | cerr<<"\nWARNING: binomial::binomial(const short&, const Integer*):\n" |
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59 | "argument out of range"<<endl; |
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60 | exponent_vector=NULL; |
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61 | // to avoid problems when deleting |
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62 | return; |
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63 | } |
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64 | |
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65 | exponent_vector=new Integer[_number_of_variables]; |
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66 | |
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67 | // determine head and tail |
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68 | if(w.compare_to_zero(exponents)>=0) |
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69 | for(short i=0;i<_number_of_variables;i++) |
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70 | exponent_vector[i]=exponents[i]; |
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71 | else |
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72 | for(short i=0;i<_number_of_variables;i++) |
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73 | exponent_vector[i]=-exponents[i]; |
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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 | |
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79 | |
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80 | binomial::binomial(const binomial& b) |
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81 | :_number_of_variables(b._number_of_variables) |
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82 | { |
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83 | exponent_vector=new Integer[_number_of_variables]; |
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84 | for(short i=0;i<_number_of_variables;i++) |
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85 | exponent_vector[i]=b.exponent_vector[i]; |
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86 | } |
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87 | |
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88 | |
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89 | |
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90 | |
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91 | #endif // NO_SUPPORT_DRIVEN_METHODS |
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92 | |
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93 | |
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94 | |
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95 | |
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96 | #ifdef SUPPORT_DRIVEN_METHODS |
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97 | |
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98 | |
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99 | |
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100 | |
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101 | binomial::binomial(const short& number_of_variables) |
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102 | :_number_of_variables(number_of_variables),head_support(0),tail_support(0) |
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103 | { |
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104 | exponent_vector=new Integer[_number_of_variables]; |
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105 | } |
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106 | |
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107 | |
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108 | |
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109 | |
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110 | binomial::binomial(const short& number_of_variables, const Integer* exponents) |
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111 | :_number_of_variables(number_of_variables),head_support(0),tail_support(0) |
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112 | { |
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113 | |
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114 | // range check for rarely used constructors |
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115 | if(_number_of_variables<=0) |
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116 | { |
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117 | exponent_vector=NULL; |
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118 | // to avoid problems when deleting |
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119 | cerr<<"\nWARNING: binomial::binomial(const short&, const Integer*):\n" |
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120 | "argument out of range"<<endl; |
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121 | return; |
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122 | } |
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123 | |
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124 | exponent_vector=new Integer[_number_of_variables]; |
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125 | |
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126 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
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127 | // number of bits of a long int |
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128 | |
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129 | |
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130 | for(short i=0;i<_number_of_variables;i++) |
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131 | { |
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132 | |
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133 | #ifdef SUPPORT_VARIABLES_FIRST |
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134 | |
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135 | Integer actual_entry=exponents[i]; |
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136 | exponent_vector[i]=actual_entry; |
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137 | |
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138 | #endif // SUPPORT_VARIABLES_FIRST |
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139 | |
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140 | #ifdef SUPPORT_VARIABLES_LAST |
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141 | |
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142 | short j=_number_of_variables-1-i; |
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143 | Integer actual_entry=exponents[j]; |
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144 | exponent_vector[j]=actual_entry; |
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145 | |
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146 | #endif // SUPPORT_VARIABLES_LAST |
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147 | |
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148 | if(i<size_of_support_vectors) |
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149 | // variable i is considered in the support vectors |
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150 | if(actual_entry>0) |
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151 | head_support|=(1<<i); |
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152 | // bit i of head_support is set to 1 (counting from 0) |
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153 | else |
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154 | if(actual_entry<0) |
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155 | tail_support|=(1<<i); |
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156 | // bit i of tail_support is set to 1 |
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157 | } |
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158 | |
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159 | } |
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160 | |
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161 | |
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162 | |
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163 | |
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164 | binomial::binomial(const short& number_of_variables, const Integer* exponents, |
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165 | const term_ordering& w) |
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166 | :_number_of_variables(number_of_variables),head_support(0),tail_support(0) |
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167 | { |
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168 | // range check for rarely used constructors |
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169 | if(_number_of_variables<=0) |
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170 | { |
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171 | cerr<<"\nWARNING: binomial::binomial(const short&, const Integer*):\n" |
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172 | "argument out of range"<<endl; |
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173 | exponent_vector=NULL; |
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174 | // to avoid problems when deleting |
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175 | return; |
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176 | } |
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177 | |
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178 | |
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179 | exponent_vector=new Integer[_number_of_variables]; |
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180 | |
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181 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
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182 | // number of bits of a long int |
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183 | |
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184 | // determine head and tail |
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185 | short sign; |
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186 | if(w.compare_to_zero(exponents)>=0) |
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187 | sign=1; |
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188 | else |
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189 | sign=-1; |
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190 | |
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191 | |
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192 | for(short i=0;i<_number_of_variables;i++) |
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193 | { |
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194 | |
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195 | #ifdef SUPPORT_VARIABLES_FIRST |
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196 | |
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197 | Integer actual_entry=sign*exponents[i]; |
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198 | exponent_vector[i]=actual_entry; |
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199 | |
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200 | #endif // SUPPORT_VARIABLES_FIRST |
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201 | |
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202 | #ifdef SUPPORT_VARIABLES_LAST |
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203 | |
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204 | short j=_number_of_variables-1-i; |
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205 | Integer actual_entry=sign*exponents[j]; |
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206 | exponent_vector[j]=actual_entry; |
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207 | |
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208 | #endif // SUPPORT_VARIABLES_LAST |
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209 | |
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210 | if(i<size_of_support_vectors) |
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211 | // variable i is considered in the support vectors |
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212 | if(actual_entry>0) |
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213 | head_support|=(1<<i); |
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214 | // bit i of head_support is set to 1 (counting from 0) |
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215 | else |
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216 | if(actual_entry<0) |
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217 | tail_support|=(1<<i); |
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218 | // bit i of tail_support is set to 1 |
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219 | } |
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220 | |
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221 | } |
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222 | |
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223 | |
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224 | |
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225 | |
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226 | binomial::binomial(const binomial& b) |
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227 | :_number_of_variables(b._number_of_variables), |
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228 | head_support(b.head_support),tail_support(b.tail_support) |
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229 | { |
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230 | exponent_vector=new Integer[_number_of_variables]; |
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231 | for(short i=0;i<_number_of_variables;i++) |
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232 | exponent_vector[i]=b.exponent_vector[i]; |
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233 | } |
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234 | |
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235 | |
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236 | |
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237 | |
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238 | #endif // SUPPORT_DRIVEN_METHODS |
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239 | |
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240 | |
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241 | |
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242 | |
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243 | binomial::~binomial() |
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244 | { |
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245 | delete[] exponent_vector; |
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246 | } |
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247 | |
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248 | |
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249 | |
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250 | |
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251 | /////////////////// object information ///////////////////////////////////// |
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252 | |
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253 | |
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254 | |
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255 | |
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256 | short binomial::number_of_variables() const |
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257 | { |
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258 | return _number_of_variables; |
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259 | } |
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260 | |
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261 | |
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262 | |
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263 | |
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264 | short binomial::error_status() const |
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265 | { |
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266 | if(_number_of_variables<0) |
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267 | return _number_of_variables; |
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268 | return 0; |
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269 | } |
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270 | |
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271 | |
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272 | |
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273 | |
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274 | //////////////////// assignment and access operators //////////////////////// |
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275 | |
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276 | |
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277 | |
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278 | |
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279 | binomial& binomial::operator=(const binomial& b) |
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280 | { |
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281 | |
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282 | if(&b==this) |
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283 | return *this; |
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284 | |
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285 | |
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286 | #ifdef SUPPORT_DRIVEN_METHODS |
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287 | |
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288 | head_support=b.head_support; |
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289 | tail_support=b.tail_support; |
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290 | |
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291 | #endif // SUPPORT_DRIVEN_METHODS |
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292 | |
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293 | if(_number_of_variables!=b._number_of_variables) |
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294 | { |
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295 | delete[] exponent_vector; |
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296 | _number_of_variables=b._number_of_variables; |
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297 | |
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298 | if(_number_of_variables<=0) |
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299 | { |
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300 | cerr<<"\nWARNING: binomial& binomial::operator=(const binomial&):\n" |
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301 | "assigment from corrupt binomial"<<endl; |
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302 | exponent_vector=NULL; |
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303 | return (*this); |
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304 | } |
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305 | |
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306 | exponent_vector=new Integer[_number_of_variables]; |
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307 | } |
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308 | |
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309 | for(short i=0;i<_number_of_variables;i++) |
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310 | exponent_vector[i]=b.exponent_vector[i]; |
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311 | |
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312 | return(*this); |
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313 | } |
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314 | |
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315 | |
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316 | |
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317 | |
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318 | Integer binomial::operator[](const short& i) const |
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319 | { |
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320 | return exponent_vector[i]; |
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321 | } |
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322 | |
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323 | |
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324 | |
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325 | |
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326 | //////////////////// comparison operators /////////////////////////////////// |
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327 | |
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328 | |
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329 | |
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330 | |
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331 | BOOLEAN binomial::operator==(const binomial& b) const |
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332 | { |
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333 | if(this == &b) |
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334 | return(TRUE); |
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335 | |
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336 | #ifdef SUPPORT_DRIVEN_METHODS |
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337 | |
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338 | if(head_support!=b.head_support) |
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339 | return(FALSE); |
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340 | if(tail_support!=b.tail_support) |
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341 | return(FALSE); |
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342 | |
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343 | #endif // SUPPORT_DRIVEN_METHODS |
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344 | |
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345 | for(short i=0;i<_number_of_variables;i++) |
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346 | if(exponent_vector[i]!=b.exponent_vector[i]) |
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347 | return(FALSE); |
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348 | return(TRUE); |
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349 | } |
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350 | |
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351 | |
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352 | |
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353 | |
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354 | BOOLEAN binomial::operator!=(const binomial& b) const |
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355 | { |
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356 | if(this == &b) |
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357 | return(FALSE); |
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358 | |
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359 | #ifdef SUPPORT_DRIVEN_METHODS |
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360 | |
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361 | if(head_support!=b.head_support) |
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362 | return(TRUE); |
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363 | if(tail_support!=b.tail_support) |
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364 | return(TRUE); |
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365 | |
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366 | #endif // SUPPORT_DRIVEN_METHODS |
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367 | |
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368 | for(short i=0;i<_number_of_variables;i++) |
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369 | if(exponent_vector[i]!=b.exponent_vector[i]) |
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370 | return(TRUE); |
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371 | return(FALSE); |
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372 | } |
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373 | |
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374 | |
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375 | |
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376 | |
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377 | // operators for efficient comparisons with the zero binomial (comp_value=0) |
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378 | |
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379 | BOOLEAN binomial::operator==(const Integer comp_value) const |
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380 | { |
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381 | |
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382 | #ifdef SUPPORT_DRIVEN_METHODS |
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383 | |
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384 | if(comp_value==0) |
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385 | { |
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386 | if(head_support!=0) |
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387 | return(FALSE); |
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388 | if(tail_support!=0) |
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389 | return(FALSE); |
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390 | } |
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391 | |
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392 | #endif // SUPPORT_DRIVEN_METHODS |
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393 | |
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394 | for(short i=0;i<_number_of_variables;i++) |
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395 | if(exponent_vector[i]!=comp_value) |
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396 | return(FALSE); |
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397 | return(TRUE); |
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398 | } |
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399 | |
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400 | |
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401 | |
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402 | |
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403 | BOOLEAN binomial::operator!=(const Integer comp_value) const |
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404 | { |
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405 | |
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406 | #ifdef SUPPORT_DRIVEN_METHODS |
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407 | |
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408 | if(comp_value==0) |
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409 | { |
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410 | if(head_support!=0) |
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411 | return(TRUE); |
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412 | if(tail_support!=0) |
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413 | return(TRUE); |
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414 | } |
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415 | |
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416 | #endif // SUPPORT_DRIVEN_METHODS |
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417 | |
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418 | for(short i=0;i<_number_of_variables;i++) |
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419 | if(exponent_vector[i]!=comp_value) |
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420 | return(TRUE); |
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421 | return(FALSE); |
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422 | } |
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423 | |
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424 | |
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425 | |
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426 | |
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427 | BOOLEAN binomial::operator<=(const Integer comp_value) const |
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428 | { |
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429 | |
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430 | #ifdef SUPPORT_DRIVEN_METHODS |
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431 | |
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432 | if(comp_value==0) |
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433 | if(head_support!=0) |
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434 | return(FALSE); |
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435 | |
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436 | #endif // SUPPORT_DRIVEN_METHODS |
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437 | |
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438 | for(short i=0;i<_number_of_variables;i++) |
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439 | if(exponent_vector[i]>comp_value) |
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440 | return(FALSE); |
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441 | return(TRUE); |
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442 | } |
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443 | |
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444 | |
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445 | |
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446 | |
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447 | BOOLEAN binomial::operator>=(const Integer comp_value) const |
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448 | { |
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449 | |
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450 | #ifdef SUPPORT_DRIVEN_METHODS |
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451 | |
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452 | if(comp_value==0) |
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453 | if(tail_support!=0) |
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454 | return(FALSE); |
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455 | |
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456 | #endif |
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457 | |
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458 | for(short i=0;i<_number_of_variables;i++) |
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459 | if(exponent_vector[i]<comp_value) |
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460 | return(FALSE); |
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461 | return(TRUE); |
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462 | } |
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463 | |
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464 | |
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465 | |
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466 | |
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467 | ////////////// basic routines for Buchbergers's algorithm ////////////////// |
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468 | |
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469 | |
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470 | |
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471 | |
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472 | Integer binomial::head_reductions_by(const binomial& b) const |
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473 | // Returns the number of possible reductions of the actual binomialŽs head |
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474 | // by the binomial b. This is the minimum of the quotients |
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475 | // exponent_vector[i]/b.exponent_vector[i] |
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476 | // where exponent_vector[i]>0 and b.exponent_vector[i]>0 |
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477 | // (0 if there are no such quotients). |
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478 | // A negative return value means b=0 or head(b)=1. |
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479 | { |
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480 | |
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481 | |
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482 | #ifdef NO_SUPPORT_DRIVEN_METHODS |
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483 | |
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484 | Integer result=-1; |
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485 | Integer new_result=-1; |
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486 | // -1 stands for infinitely many reductions |
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487 | |
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488 | for(short i=0;i<_number_of_variables;i++) |
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489 | // explicit sign tests for all components |
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490 | { |
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491 | Integer actual_b_component=b.exponent_vector[i]; |
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492 | |
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493 | if(actual_b_component>0) |
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494 | // else variable i is not involved in the head of b |
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495 | { |
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496 | Integer actual_component=exponent_vector[i]; |
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497 | |
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498 | if(actual_component<actual_b_component) |
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499 | return 0; |
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500 | |
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501 | new_result=(Integer) (actual_component/actual_b_component); |
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502 | |
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503 | // new_result>=1 |
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504 | if((new_result<result) || (result==-1)) |
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505 | // new (or first) minimum |
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506 | result=new_result; |
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507 | } |
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508 | } |
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509 | |
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510 | #endif // NO_SUPPORT_DRIVEN_METHODS |
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511 | |
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512 | |
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513 | #ifdef SUPPORT_DRIVEN_METHODS |
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514 | |
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515 | if((head_support&b.head_support)!=b.head_support) |
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516 | // head support of b not contained in head support, no reduction possible |
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517 | return 0; |
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518 | |
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519 | |
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520 | Integer result=-1; |
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521 | Integer new_result=-1; |
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522 | // -1 stands for infinitely many reductions |
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523 | |
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524 | |
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525 | short size_of_support_vectors=CHAR_BIT*sizeof(long); |
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526 | // number of bits of a long int |
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527 | if(size_of_support_vectors>_number_of_variables) |
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528 | size_of_support_vectors=_number_of_variables; |
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529 | // number of components of the support vectors |
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530 | |
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531 | |
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532 | #ifdef SUPPORT_VARIABLES_FIRST |
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533 | |
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534 | for(short i=0;i<size_of_support_vectors;i++) |
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535 | // test support variables |
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536 | |
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537 | if(b.head_support&(1<<i)) |
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538 | // bit i of b.head_support is 1 |
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539 | { |
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540 | new_result=(Integer) (exponent_vector[i]/b.exponent_vector[i]); |
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541 | // remember that exponent_vector[i]>0 ! |
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542 | // (head support contains that of b) |
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543 | |
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544 | if(new_result==0) |
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545 | // exponent_vector[i]<b.exponent_vector[i] |
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546 | return 0; |
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547 | |
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548 | // new_result>=1 |
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549 | if((new_result<result) || (result==-1)) |
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550 | // new (or first) minimum |
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551 | result=new_result; |
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552 | } |
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553 | |
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554 | |
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555 | for(short i=size_of_support_vectors;i<_number_of_variables;i++) |
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556 | // test non-support variables |
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557 | // from now on we need explicit sign tests |
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558 | { |
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559 | Integer actual_b_component=b.exponent_vector[i]; |
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560 | |
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561 | if(actual_b_component>0) |
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562 | // else variable i is not involved in the head of b |
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563 | { |
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564 | Integer actual_component=exponent_vector[i]; |
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565 | |
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566 | if(actual_component<actual_b_component) |
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567 | return 0; |
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568 | |
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569 | new_result=(Integer) (actual_component/actual_b_component); |
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570 | |
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571 | // new_result>=1 |
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572 | if((new_result<result) || (result==-1)) |
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573 | // new (or first) minimum |
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574 | result=new_result; |
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575 | } |
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576 | } |
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577 | |
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578 | #endif // SUPPORT_VARIABLES_FIRST |
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579 | |
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580 | |
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581 | #ifdef SUPPORT_VARIABLES_LAST |
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582 | |
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583 | for(short i=0;i<size_of_support_vectors;i++) |
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584 | // test support variables |
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585 | |
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586 | if(b.head_support&(1<<i)) |
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587 | // bit i of b.head_support is 1 |
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588 | { |
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589 | short j=_number_of_variables-1-i; |
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590 | new_result=(Integer) (exponent_vector[j]/ b.exponent_vector[j]); |
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591 | // remember that exponent_vector[_number_of_variables-1-i]>0 ! |
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592 | // (head support contains that of b) |
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593 | |
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594 | if(new_result==0) |
---|
595 | // exponent_vector[_number_of_variables-1-i] |
---|
596 | // <b.exponent_vector[_number_of_variables-1-i] |
---|
597 | return 0; |
---|
598 | |
---|
599 | // new_result>=1 |
---|
600 | if((new_result<result) || (result==-1)) |
---|
601 | // new (or first) minimum |
---|
602 | result=new_result; |
---|
603 | } |
---|
604 | |
---|
605 | |
---|
606 | for(short i=size_of_support_vectors;i<_number_of_variables;i++) |
---|
607 | // test non-support variables |
---|
608 | // from now on we need explicit sign tests |
---|
609 | { |
---|
610 | short j=_number_of_variables-1-i; |
---|
611 | Integer actual_b_component=b.exponent_vector[j]; |
---|
612 | |
---|
613 | if(actual_b_component>0) |
---|
614 | // else variable number_of_variables-1-i is not involved in the head of b |
---|
615 | { |
---|
616 | Integer actual_component=exponent_vector[j]; |
---|
617 | |
---|
618 | if(actual_component<actual_b_component) |
---|
619 | return 0; |
---|
620 | |
---|
621 | new_result=(Integer) (actual_component/actual_b_component); |
---|
622 | |
---|
623 | // new_result>=1 |
---|
624 | if((new_result<result) || (result==-1)) |
---|
625 | // new (or first) minimum |
---|
626 | result=new_result; |
---|
627 | } |
---|
628 | } |
---|
629 | |
---|
630 | #endif // SUPPORT_VARIABLES_LAST |
---|
631 | |
---|
632 | |
---|
633 | #endif // SUPPORT_DRIVEN_METHODS |
---|
634 | |
---|
635 | |
---|
636 | return(result); |
---|
637 | } |
---|
638 | |
---|
639 | |
---|
640 | |
---|
641 | |
---|
642 | Integer binomial::tail_reductions_by(const binomial& b) const |
---|
643 | // Returns the number of possible reductions of the actual binomialŽs tail |
---|
644 | // by the binomial b. This is the minimum of the quotients |
---|
645 | // - exponent_vector[i]/b.exponent_vector[i] |
---|
646 | // where exponent_vector[i]<0 and b.exponent_vector[i]>0 |
---|
647 | // (0 if there are no such quotients). |
---|
648 | // A negative return value means b=0 or head(b)=1. |
---|
649 | { |
---|
650 | |
---|
651 | |
---|
652 | #ifdef NO_SUPPORT_DRIVEN_METHODS |
---|
653 | |
---|
654 | Integer result=-1; |
---|
655 | Integer new_result=-1; |
---|
656 | // -1 stands for infinitely many reductions |
---|
657 | |
---|
658 | for(short i=0;i<_number_of_variables;i++) |
---|
659 | // explicit sign tests for all components |
---|
660 | { |
---|
661 | Integer actual_b_component=b.exponent_vector[i]; |
---|
662 | |
---|
663 | if(actual_b_component>0) |
---|
664 | // else variable i is not involved in the head of b |
---|
665 | { |
---|
666 | Integer actual_component=-exponent_vector[i]; |
---|
667 | |
---|
668 | if(actual_component<actual_b_component) |
---|
669 | return 0; |
---|
670 | |
---|
671 | new_result=(Integer) (actual_component/actual_b_component); |
---|
672 | |
---|
673 | // new_result>=1 |
---|
674 | if((new_result<result) || (result==-1)) |
---|
675 | // new (or first) minimum |
---|
676 | result=new_result; |
---|
677 | } |
---|
678 | } |
---|
679 | |
---|
680 | #endif // NO_SUPPORT_DRIVEN_METHODS |
---|
681 | |
---|
682 | |
---|
683 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
684 | |
---|
685 | if((tail_support&b.head_support)!=b.head_support) |
---|
686 | // head support of b not contained in tail support, no reduction possible |
---|
687 | return 0; |
---|
688 | |
---|
689 | |
---|
690 | Integer result=-1; |
---|
691 | Integer new_result=-1; |
---|
692 | // -1 stands for infinitely many reductions |
---|
693 | |
---|
694 | |
---|
695 | short size_of_support_vectors=CHAR_BIT*sizeof(long); |
---|
696 | // number of bits of a long int |
---|
697 | if(size_of_support_vectors>_number_of_variables) |
---|
698 | size_of_support_vectors=_number_of_variables; |
---|
699 | // number of components of the support vectors |
---|
700 | |
---|
701 | |
---|
702 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
703 | |
---|
704 | for(short i=0;i<size_of_support_vectors;i++) |
---|
705 | // test support variables |
---|
706 | |
---|
707 | if(b.head_support&(1<<i)) |
---|
708 | // bit i of b.head_support is 1 |
---|
709 | { |
---|
710 | new_result=(Integer) (-exponent_vector[i]/b.exponent_vector[i]); |
---|
711 | // remember that exponent_vector[i]<0 ! |
---|
712 | // (tail support contains the head support of b) |
---|
713 | |
---|
714 | if(new_result==0) |
---|
715 | // -exponent_vector[i]<b.exponent_vector[i] |
---|
716 | return 0; |
---|
717 | |
---|
718 | // new_result>=1 |
---|
719 | if((new_result<result) || (result==-1)) |
---|
720 | // new (or first) minimum |
---|
721 | result=new_result; |
---|
722 | } |
---|
723 | |
---|
724 | |
---|
725 | for(short i=size_of_support_vectors;i<_number_of_variables;i++) |
---|
726 | // test non-support variables |
---|
727 | // from now on we need explicit sign tests |
---|
728 | { |
---|
729 | Integer actual_b_component=b.exponent_vector[i]; |
---|
730 | |
---|
731 | if(actual_b_component>0) |
---|
732 | // else variable i is not involved in the head of b |
---|
733 | { |
---|
734 | Integer actual_component=-exponent_vector[i]; |
---|
735 | |
---|
736 | if(actual_component<actual_b_component) |
---|
737 | return 0; |
---|
738 | |
---|
739 | new_result=(Integer) (actual_component/actual_b_component); |
---|
740 | |
---|
741 | // new_result>=1 |
---|
742 | if((new_result<result) || (result==-1)) |
---|
743 | // new (or first) minimum |
---|
744 | result=new_result; |
---|
745 | } |
---|
746 | } |
---|
747 | |
---|
748 | #endif // SUPPORT_VARIABLES_FIRST |
---|
749 | |
---|
750 | |
---|
751 | #ifdef SUPPORT_VARIABLES_LAST |
---|
752 | |
---|
753 | for(short i=0;i<size_of_support_vectors;i++) |
---|
754 | // test support variables |
---|
755 | |
---|
756 | if(b.head_support&(1<<i)) |
---|
757 | // bit i of b.head_support is 1 |
---|
758 | { |
---|
759 | short j=_number_of_variables-1-i; |
---|
760 | new_result=(Integer) (-exponent_vector[j] / b.exponent_vector[j]); |
---|
761 | // remember that exponent_vector[_number_of_variables-1-i]<0 ! |
---|
762 | // (tail support contains the head support of b) |
---|
763 | |
---|
764 | if(new_result==0) |
---|
765 | // -exponent_vector[_number_of_variables-1-i] |
---|
766 | // <b.exponent_vector[_number_of_variables-1-i] |
---|
767 | return 0; |
---|
768 | |
---|
769 | // new_result>=1 |
---|
770 | if((new_result<result) || (result==-1)) |
---|
771 | // new (or first) minimum |
---|
772 | result=new_result; |
---|
773 | } |
---|
774 | |
---|
775 | |
---|
776 | for(short i=size_of_support_vectors;i<_number_of_variables;i++) |
---|
777 | // test non-support variables |
---|
778 | // from now on we need explicit sign tests |
---|
779 | { |
---|
780 | short j=_number_of_variables-1-i; |
---|
781 | Integer actual_b_component=b.exponent_vector[j]; |
---|
782 | |
---|
783 | if(actual_b_component>0) |
---|
784 | // else variable number_of_variables-1-i is not involved in the head of b |
---|
785 | { |
---|
786 | Integer actual_component=-exponent_vector[j]; |
---|
787 | |
---|
788 | if(actual_component<actual_b_component) |
---|
789 | return 0; |
---|
790 | |
---|
791 | new_result=(Integer) (actual_component/actual_b_component); |
---|
792 | |
---|
793 | // new_result>=1 |
---|
794 | if((new_result<result) || (result==-1)) |
---|
795 | // new (or first) minimum |
---|
796 | result=new_result; |
---|
797 | } |
---|
798 | } |
---|
799 | |
---|
800 | #endif // SUPPORT_VARIABLES_LAST |
---|
801 | |
---|
802 | |
---|
803 | #endif // SUPPORT_DRIVEN_METHODS |
---|
804 | |
---|
805 | |
---|
806 | return(result); |
---|
807 | } |
---|
808 | |
---|
809 | |
---|
810 | |
---|
811 | |
---|
812 | int binomial::reduce_head_by(const binomial& b, const term_ordering& w) |
---|
813 | { |
---|
814 | Integer reduction_number=head_reductions_by(b); |
---|
815 | if(reduction_number<=0) |
---|
816 | return 0; |
---|
817 | |
---|
818 | for(short i=0;i<_number_of_variables;i++) |
---|
819 | exponent_vector[i]-=(reduction_number * b.exponent_vector[i]); |
---|
820 | // multiple reduction |
---|
821 | // reduction corresponds to subtraction of vectors |
---|
822 | |
---|
823 | short sign=w.compare_to_zero(exponent_vector); |
---|
824 | |
---|
825 | |
---|
826 | #ifdef NO_SUPPORT_DRIVEN_METHODS |
---|
827 | |
---|
828 | if(sign==0) |
---|
829 | // binomial reduced to zero |
---|
830 | return 2; |
---|
831 | |
---|
832 | for(short i=0;i<_number_of_variables;i++) |
---|
833 | exponent_vector[i]*=sign; |
---|
834 | |
---|
835 | #endif // NO_SUPPORT_DRIVEN_METHODS |
---|
836 | |
---|
837 | |
---|
838 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
839 | |
---|
840 | head_support=0; |
---|
841 | tail_support=0; |
---|
842 | |
---|
843 | if(sign==0) |
---|
844 | // binomial reduced to zero |
---|
845 | return 2; |
---|
846 | |
---|
847 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
---|
848 | |
---|
849 | |
---|
850 | // recompute the support vectors |
---|
851 | |
---|
852 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
853 | |
---|
854 | for(short i=0;i<_number_of_variables;i++) |
---|
855 | { |
---|
856 | |
---|
857 | Integer& actual_entry=exponent_vector[i]; |
---|
858 | // to avoid unnecessary pointer arithmetic |
---|
859 | |
---|
860 | actual_entry*=sign; |
---|
861 | |
---|
862 | if(i<size_of_support_vectors) |
---|
863 | if(actual_entry>0) |
---|
864 | head_support|=(1<<i); |
---|
865 | else |
---|
866 | if(actual_entry<0) |
---|
867 | tail_support|=(1<<i); |
---|
868 | } |
---|
869 | |
---|
870 | #endif // SUPPORT_VARIABLES_FIRST |
---|
871 | |
---|
872 | |
---|
873 | #ifdef SUPPORT_VARIABLES_LAST |
---|
874 | |
---|
875 | for(short i=0;i<_number_of_variables;i++) |
---|
876 | { |
---|
877 | Integer& actual_entry=exponent_vector[_number_of_variables-1-i]; |
---|
878 | // to avoid unneccessary pointer arithmetic |
---|
879 | |
---|
880 | actual_entry*=sign; |
---|
881 | |
---|
882 | if(i<size_of_support_vectors) |
---|
883 | if(actual_entry>0) |
---|
884 | head_support|=(1<<i); |
---|
885 | else |
---|
886 | if(actual_entry<0) |
---|
887 | tail_support|=(1<<i); |
---|
888 | } |
---|
889 | |
---|
890 | #endif // SUPPORT_VARIABLES_LAST |
---|
891 | |
---|
892 | |
---|
893 | #endif // SUPPORT_DRIVEN_METHODS |
---|
894 | |
---|
895 | return 1; |
---|
896 | } |
---|
897 | |
---|
898 | |
---|
899 | |
---|
900 | |
---|
901 | int binomial::reduce_tail_by(const binomial& b, const term_ordering& w) |
---|
902 | { |
---|
903 | Integer reduction_number=tail_reductions_by(b); |
---|
904 | if(reduction_number<=0) |
---|
905 | return 0; |
---|
906 | |
---|
907 | for(short i=0;i<_number_of_variables;i++) |
---|
908 | exponent_vector[i]+=(reduction_number * b.exponent_vector[i]); |
---|
909 | // multiple reduction |
---|
910 | // reduction corresponds to addition of vectors |
---|
911 | |
---|
912 | // a tail reduction does not require a sign check |
---|
913 | |
---|
914 | |
---|
915 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
916 | |
---|
917 | head_support=0; |
---|
918 | tail_support=0; |
---|
919 | |
---|
920 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
---|
921 | |
---|
922 | |
---|
923 | // recompute the support vectors |
---|
924 | |
---|
925 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
926 | |
---|
927 | for(short i=0;i<_number_of_variables;i++) |
---|
928 | { |
---|
929 | |
---|
930 | Integer& actual_entry=exponent_vector[i]; |
---|
931 | // to avoid unnecessary pointer arithmetic |
---|
932 | |
---|
933 | if(i<size_of_support_vectors) |
---|
934 | if(actual_entry>0) |
---|
935 | head_support|=(1<<i); |
---|
936 | else |
---|
937 | if(actual_entry<0) |
---|
938 | tail_support|=(1<<i); |
---|
939 | } |
---|
940 | |
---|
941 | #endif // SUPPORT_VARIABLES_FIRST |
---|
942 | |
---|
943 | |
---|
944 | #ifdef SUPPORT_VARIABLES_LAST |
---|
945 | |
---|
946 | for(short i=0;i<_number_of_variables;i++) |
---|
947 | { |
---|
948 | Integer& actual_entry=exponent_vector[_number_of_variables-1-i]; |
---|
949 | // to avoid unneccessary pointer arithmetic |
---|
950 | |
---|
951 | if(i<size_of_support_vectors) |
---|
952 | if(actual_entry>0) |
---|
953 | head_support|=(1<<i); |
---|
954 | else |
---|
955 | if(actual_entry<0) |
---|
956 | tail_support|=(1<<i); |
---|
957 | } |
---|
958 | |
---|
959 | #endif // SUPPORT_VARIABLES_LAST |
---|
960 | |
---|
961 | |
---|
962 | #endif // SUPPORT_DRIVEN_METHODS |
---|
963 | |
---|
964 | return 1; |
---|
965 | } |
---|
966 | |
---|
967 | |
---|
968 | |
---|
969 | |
---|
970 | binomial& S_binomial(const binomial& a, const binomial& b, |
---|
971 | const term_ordering& w) |
---|
972 | { |
---|
973 | binomial* S_bin=new binomial(a._number_of_variables); |
---|
974 | binomial& result=*S_bin; |
---|
975 | // Note that we allocate memory for the result binomial. We often use |
---|
976 | // pointers or references as argument and return types because the |
---|
977 | // generating binomials of an ideal are kept in lists. For the performance |
---|
978 | // of Buchberger's algorithm it it very important to avoid local copies |
---|
979 | // of binomials, so a lot of attention is paid on the choice of argument |
---|
980 | // and return types. As this choice is done in order to improve performance, |
---|
981 | // it might be a bad choice with respect to code reuse (there are some |
---|
982 | // dangerous constructions). |
---|
983 | |
---|
984 | for(short i=0;i<result._number_of_variables;i++) |
---|
985 | result.exponent_vector[i]=a.exponent_vector[i]-b.exponent_vector[i]; |
---|
986 | // The S-binomial corresponds to the vector difference. |
---|
987 | |
---|
988 | // compute head and tail |
---|
989 | short sign=w.compare_to_zero(result.exponent_vector); |
---|
990 | |
---|
991 | |
---|
992 | #ifdef NO_SUPPORT_DRIVEN_METHODS |
---|
993 | |
---|
994 | if(sign==0) |
---|
995 | // binomial reduced to zero |
---|
996 | return result; |
---|
997 | |
---|
998 | for(short i=0;i<result._number_of_variables;i++) |
---|
999 | result.exponent_vector[i]*=sign; |
---|
1000 | |
---|
1001 | #endif // NO_SUPPORT_DRIVEN_METHODS |
---|
1002 | |
---|
1003 | |
---|
1004 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1005 | |
---|
1006 | result.head_support=0; |
---|
1007 | result.tail_support=0; |
---|
1008 | |
---|
1009 | if(sign==0) |
---|
1010 | // binomial reduced to zero |
---|
1011 | return result; |
---|
1012 | |
---|
1013 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
---|
1014 | |
---|
1015 | |
---|
1016 | // recompute the support vectors |
---|
1017 | |
---|
1018 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
1019 | |
---|
1020 | for(short i=0;i<result._number_of_variables;i++) |
---|
1021 | { |
---|
1022 | |
---|
1023 | Integer& actual_entry=result.exponent_vector[i]; |
---|
1024 | // to avoid unnecessary pointer arithmetic |
---|
1025 | |
---|
1026 | actual_entry*=sign; |
---|
1027 | |
---|
1028 | if(i<size_of_support_vectors) |
---|
1029 | if(actual_entry>0) |
---|
1030 | result.head_support|=(1<<i); |
---|
1031 | else |
---|
1032 | if(actual_entry<0) |
---|
1033 | result.tail_support|=(1<<i); |
---|
1034 | } |
---|
1035 | |
---|
1036 | #endif // SUPPORT_VARIABLES_FIRST |
---|
1037 | |
---|
1038 | |
---|
1039 | #ifdef SUPPORT_VARIABLES_LAST |
---|
1040 | |
---|
1041 | for(short i=0;i<result._number_of_variables;i++) |
---|
1042 | { |
---|
1043 | Integer& actual_entry=result.exponent_vector |
---|
1044 | [result._number_of_variables-1-i]; |
---|
1045 | // to avoid unneccessary pointer arithmetic |
---|
1046 | |
---|
1047 | actual_entry*=sign; |
---|
1048 | |
---|
1049 | if(i<size_of_support_vectors) |
---|
1050 | if(actual_entry>0) |
---|
1051 | result.head_support|=(1<<i); |
---|
1052 | else |
---|
1053 | if(actual_entry<0) |
---|
1054 | result.tail_support|=(1<<i); |
---|
1055 | } |
---|
1056 | |
---|
1057 | #endif // SUPPORT_VARIABLES_LAST |
---|
1058 | |
---|
1059 | |
---|
1060 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1061 | |
---|
1062 | |
---|
1063 | return result; |
---|
1064 | } |
---|
1065 | |
---|
1066 | |
---|
1067 | |
---|
1068 | |
---|
1069 | ///////////// criteria for unnecessary S-pairs /////////////////////////////// |
---|
1070 | |
---|
1071 | // The criteria are programmed in a way that tries to minimize pointer |
---|
1072 | // arithmetic. Therefore the code may appear a little bit inflated. |
---|
1073 | |
---|
1074 | |
---|
1075 | |
---|
1076 | |
---|
1077 | BOOLEAN relatively_prime(const binomial& a, const binomial& b) |
---|
1078 | { |
---|
1079 | |
---|
1080 | #ifdef NO_SUPPORT_DRIVEN_METHODS |
---|
1081 | |
---|
1082 | // look at all variables |
---|
1083 | for(short i=0;i<a._number_of_variables;i++) |
---|
1084 | if((a.exponent_vector[i]>0) && (b.exponent_vector[i]>0)) |
---|
1085 | return FALSE; |
---|
1086 | |
---|
1087 | return TRUE; |
---|
1088 | |
---|
1089 | #endif // NO_SUPPORT_DRIVEN_METHODS |
---|
1090 | |
---|
1091 | |
---|
1092 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1093 | |
---|
1094 | if((a.head_support & b.head_support)!=0) |
---|
1095 | // common support variable in the heads |
---|
1096 | return FALSE; |
---|
1097 | |
---|
1098 | // no common support variable in the heads, look at remaining variables |
---|
1099 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
---|
1100 | |
---|
1101 | |
---|
1102 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
1103 | |
---|
1104 | for(short i=size_of_support_vectors;i<a._number_of_variables;i++) |
---|
1105 | if((a.exponent_vector[i]>0) && (b.exponent_vector[i]>0)) |
---|
1106 | return FALSE; |
---|
1107 | |
---|
1108 | return TRUE; |
---|
1109 | |
---|
1110 | #endif // SUPPORT_VARIABLES_FIRST |
---|
1111 | |
---|
1112 | |
---|
1113 | #ifdef SUPPORT_VARIABLES_LAST |
---|
1114 | |
---|
1115 | for(short i=a._number_of_variables-1-size_of_support_vectors;i>=0;i--) |
---|
1116 | if((a.exponent_vector[i]>0) && (b.exponent_vector[i]>0)) |
---|
1117 | return FALSE; |
---|
1118 | |
---|
1119 | return TRUE; |
---|
1120 | |
---|
1121 | #endif // SUPPORT_VARIABLES_LAST |
---|
1122 | |
---|
1123 | |
---|
1124 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1125 | |
---|
1126 | } |
---|
1127 | |
---|
1128 | |
---|
1129 | |
---|
1130 | |
---|
1131 | BOOLEAN M(const binomial& a, const binomial& b, const binomial& c) |
---|
1132 | // Returns TRUE iff lcm(head(a),head(c)) divides properly lcm(head(b),head(c)). |
---|
1133 | // This is checked by comparing the positive components of the exponent |
---|
1134 | // vectors. |
---|
1135 | { |
---|
1136 | |
---|
1137 | |
---|
1138 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1139 | |
---|
1140 | long b_or_c=b.head_support|c.head_support; |
---|
1141 | |
---|
1142 | if((a.head_support|b_or_c) != b_or_c) |
---|
1143 | return FALSE; |
---|
1144 | // The support of lcm(head(a),head(c)) equals the union of the head supports |
---|
1145 | // of a and c. The above condition verifies if the support of |
---|
1146 | // lcm(head(a),head(c)) is contained in the support of lcm(head(b),head(c)) |
---|
1147 | // by checking if head a involves a variable that is not involved in |
---|
1148 | // head(b) or head(c). |
---|
1149 | |
---|
1150 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1151 | |
---|
1152 | |
---|
1153 | BOOLEAN properly=FALSE; |
---|
1154 | |
---|
1155 | for(short i=0;i<a._number_of_variables;i++) |
---|
1156 | { |
---|
1157 | Integer a_exponent=a.exponent_vector[i]; |
---|
1158 | Integer b_exponent=b.exponent_vector[i]; |
---|
1159 | Integer c_exponent=c.exponent_vector[i]; |
---|
1160 | Integer m1=MAXIMUM(a_exponent,c_exponent); |
---|
1161 | Integer m2=MAXIMUM(b_exponent,c_exponent); |
---|
1162 | |
---|
1163 | if(m1>0) |
---|
1164 | { |
---|
1165 | if(m1>m2) |
---|
1166 | return FALSE; |
---|
1167 | if(m1<m2) |
---|
1168 | properly=TRUE; |
---|
1169 | } |
---|
1170 | } |
---|
1171 | |
---|
1172 | return properly; |
---|
1173 | } |
---|
1174 | |
---|
1175 | |
---|
1176 | |
---|
1177 | |
---|
1178 | BOOLEAN F(const binomial& a, const binomial& b, const binomial& c) |
---|
1179 | // verifies if lcm(head(a),head(c))=lcm(head(b),head(c)) |
---|
1180 | { |
---|
1181 | |
---|
1182 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1183 | |
---|
1184 | if((a.head_support|c.head_support)!=(b.head_support|c.head_support)) |
---|
1185 | return FALSE; |
---|
1186 | // The above condition verifies if the support of lcm(head(a),head(c)) |
---|
1187 | // equals the support of lcm(head(b),head(c)). |
---|
1188 | |
---|
1189 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1190 | |
---|
1191 | for(short i=0;i<a._number_of_variables;i++) |
---|
1192 | { |
---|
1193 | Integer a_exponent=a.exponent_vector[i]; |
---|
1194 | Integer b_exponent=b.exponent_vector[i]; |
---|
1195 | Integer c_exponent=c.exponent_vector[i]; |
---|
1196 | Integer m1=MAXIMUM(a_exponent,c_exponent); |
---|
1197 | Integer m2=MAXIMUM(b_exponent,c_exponent); |
---|
1198 | |
---|
1199 | if((m1!=m2) && (m1>0 || m2>0)) |
---|
1200 | return FALSE; |
---|
1201 | } |
---|
1202 | |
---|
1203 | return TRUE; |
---|
1204 | } |
---|
1205 | |
---|
1206 | |
---|
1207 | |
---|
1208 | |
---|
1209 | BOOLEAN B(const binomial& a, const binomial& b, const binomial& c) |
---|
1210 | // verifies if head(a) divides lcm(head(b),head(c)) and |
---|
1211 | // lcm(head(a),head(b))!=lcm(head(b),head(c))!=lcm(head(a),head(c)) |
---|
1212 | { |
---|
1213 | |
---|
1214 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1215 | |
---|
1216 | long a_or_b=a.head_support|b.head_support; |
---|
1217 | long a_or_c=a.head_support|c.head_support; |
---|
1218 | long b_or_c=b.head_support|c.head_support; |
---|
1219 | |
---|
1220 | if((a.head_support & b_or_c)!=a.head_support) |
---|
1221 | return FALSE; |
---|
1222 | // The above condition verifies if the support of head(a) is contained in |
---|
1223 | // the support of lcm(head(b),head(c)). |
---|
1224 | |
---|
1225 | if( (a_or_c != b_or_c) && (a_or_b != b_or_c)) |
---|
1226 | // Then the inequality conditions are guaranteed... |
---|
1227 | { |
---|
1228 | for(short i=0;i<a._number_of_variables;i++) |
---|
1229 | { |
---|
1230 | Integer b_exponent=b.exponent_vector[i]; |
---|
1231 | Integer c_exponent=c.exponent_vector[i]; |
---|
1232 | |
---|
1233 | if(a.exponent_vector[i]>MAXIMUM(b_exponent,c_exponent)) |
---|
1234 | return FALSE; |
---|
1235 | } |
---|
1236 | |
---|
1237 | return (TRUE); |
---|
1238 | } |
---|
1239 | |
---|
1240 | |
---|
1241 | if(a_or_b != b_or_c) |
---|
1242 | // Then the first inequality conditions is guaranteed... |
---|
1243 | // Verifie only the second. |
---|
1244 | { |
---|
1245 | BOOLEAN not_equal=FALSE; |
---|
1246 | |
---|
1247 | for(short i=0;i<a._number_of_variables;i++) |
---|
1248 | { |
---|
1249 | Integer a_exponent=a.exponent_vector[i]; |
---|
1250 | Integer b_exponent=b.exponent_vector[i]; |
---|
1251 | Integer c_exponent=c.exponent_vector[i]; |
---|
1252 | Integer m=MAXIMUM(b_exponent, c_exponent); |
---|
1253 | |
---|
1254 | if(a_exponent>m) |
---|
1255 | return FALSE; |
---|
1256 | |
---|
1257 | if(MAXIMUM(a_exponent,c_exponent) != m) |
---|
1258 | not_equal=TRUE; |
---|
1259 | } |
---|
1260 | return(not_equal); |
---|
1261 | } |
---|
1262 | |
---|
1263 | |
---|
1264 | if( a_or_c != b_or_c ) |
---|
1265 | // Then the second inequality conditions is guaranteed... |
---|
1266 | // Verifie only the first. |
---|
1267 | { |
---|
1268 | BOOLEAN not_equal=FALSE; |
---|
1269 | |
---|
1270 | for(short i=0;i<a._number_of_variables;i++) |
---|
1271 | { |
---|
1272 | Integer a_exponent=a.exponent_vector[i]; |
---|
1273 | Integer b_exponent=b.exponent_vector[i]; |
---|
1274 | Integer c_exponent=c.exponent_vector[i]; |
---|
1275 | Integer m=MAXIMUM(b_exponent, c_exponent); |
---|
1276 | |
---|
1277 | if(a_exponent > m) |
---|
1278 | return FALSE; |
---|
1279 | |
---|
1280 | if(MAXIMUM(a_exponent,b_exponent) != m) |
---|
1281 | not_equal=TRUE; |
---|
1282 | } |
---|
1283 | return(not_equal); |
---|
1284 | } |
---|
1285 | |
---|
1286 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1287 | |
---|
1288 | |
---|
1289 | BOOLEAN not_equal_1=FALSE; |
---|
1290 | BOOLEAN not_equal_2=FALSE; |
---|
1291 | |
---|
1292 | for(short i=0;i<a._number_of_variables;i++) |
---|
1293 | { |
---|
1294 | Integer a_exponent=a.exponent_vector[i]; |
---|
1295 | Integer b_exponent=b.exponent_vector[i]; |
---|
1296 | Integer c_exponent=c.exponent_vector[i]; |
---|
1297 | Integer m=MAXIMUM(b_exponent, c_exponent); |
---|
1298 | |
---|
1299 | if(a_exponent > m) |
---|
1300 | return FALSE; |
---|
1301 | |
---|
1302 | if(MAXIMUM(a_exponent,b_exponent) != m) |
---|
1303 | not_equal_1=TRUE; |
---|
1304 | if(MAXIMUM(a_exponent,c_exponent) != m) |
---|
1305 | not_equal_2=TRUE; |
---|
1306 | } |
---|
1307 | |
---|
1308 | return (not_equal_1 && not_equal_2); |
---|
1309 | |
---|
1310 | } |
---|
1311 | |
---|
1312 | |
---|
1313 | |
---|
1314 | |
---|
1315 | BOOLEAN second_crit(const binomial& a, const binomial& b, |
---|
1316 | const binomial& c) |
---|
1317 | // verifies if head(a) divides lcm(head(b),head(c)) |
---|
1318 | { |
---|
1319 | |
---|
1320 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1321 | |
---|
1322 | if((a.head_support & (b.head_support|c.head_support))!=a.head_support) |
---|
1323 | return FALSE; |
---|
1324 | // The above condition verifies if the support of head(a) is contained in |
---|
1325 | // the support of lcm(head(b),head(c)) |
---|
1326 | |
---|
1327 | #endif // SUPPORT_DRIVEN_METHODS. |
---|
1328 | |
---|
1329 | for(short i=0;i<a._number_of_variables;i++) |
---|
1330 | { |
---|
1331 | Integer b_exponent=b.exponent_vector[i]; |
---|
1332 | Integer c_exponent=c.exponent_vector[i]; |
---|
1333 | |
---|
1334 | if(a.exponent_vector[i]>MAXIMUM(b_exponent,c_exponent)) |
---|
1335 | return FALSE; |
---|
1336 | } |
---|
1337 | |
---|
1338 | return (TRUE); |
---|
1339 | } |
---|
1340 | |
---|
1341 | |
---|
1342 | |
---|
1343 | |
---|
1344 | //////// special routines needed by the IP-algorithms /////////////////////// |
---|
1345 | |
---|
1346 | |
---|
1347 | |
---|
1348 | |
---|
1349 | BOOLEAN binomial::involves_elimination_variables(const term_ordering& w) |
---|
1350 | { |
---|
1351 | // The use of support information would require the distinction of various |
---|
1352 | // cases here (relation between the number of variables to eliminate |
---|
1353 | // and the number of support variables) and be quite difficult. |
---|
1354 | // It is doubtful if this would improve performance. |
---|
1355 | // As this function is not used in BuchbergerŽs algorithm (and therefore |
---|
1356 | // rather rarely), I renounce to implement this. |
---|
1357 | |
---|
1358 | for(short i=0;i<w.number_of_elimination_variables();i++) |
---|
1359 | // elimination variables are always the last ones |
---|
1360 | if(exponent_vector[_number_of_variables-1-i]!=0) |
---|
1361 | return TRUE; |
---|
1362 | |
---|
1363 | return FALSE; |
---|
1364 | } |
---|
1365 | |
---|
1366 | |
---|
1367 | |
---|
1368 | |
---|
1369 | BOOLEAN binomial::drop_elimination_variables(const term_ordering& w) |
---|
1370 | { |
---|
1371 | _number_of_variables-=w.number_of_elimination_variables(); |
---|
1372 | // dangerous (no compatibility check)!! |
---|
1373 | |
---|
1374 | // copy components of interest to save memory |
---|
1375 | // the leading term has to be recomputed!! |
---|
1376 | |
---|
1377 | Integer *aux=exponent_vector; |
---|
1378 | exponent_vector=new Integer[_number_of_variables]; |
---|
1379 | |
---|
1380 | if(w.weight(aux)>=0) |
---|
1381 | for(short i=0;i<_number_of_variables;i++) |
---|
1382 | exponent_vector[i]=aux[i]; |
---|
1383 | else |
---|
1384 | for(short i=0;i<_number_of_variables;i++) |
---|
1385 | exponent_vector[i]=-aux[i]; |
---|
1386 | |
---|
1387 | delete[] aux; |
---|
1388 | |
---|
1389 | |
---|
1390 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1391 | |
---|
1392 | // Recompute head and tail. |
---|
1393 | // Normally, this routine is only called for binomials that do not involve |
---|
1394 | // the variables to eliminate. But if SUPPORT_VARIABLES_LAST is enabled, |
---|
1395 | // the support changes in spite of this. Therefore, the support is |
---|
1396 | // recomputed... For the same reasons as mentionned in the preceeding |
---|
1397 | // routine, the existing support information is not used. |
---|
1398 | |
---|
1399 | head_support=0; |
---|
1400 | tail_support=0; |
---|
1401 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
---|
1402 | if(size_of_support_vectors>_number_of_variables) |
---|
1403 | size_of_support_vectors=_number_of_variables; |
---|
1404 | |
---|
1405 | |
---|
1406 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
1407 | |
---|
1408 | for(short i=0;i<size_of_support_vectors;i++) |
---|
1409 | { |
---|
1410 | Integer actual_entry=exponent_vector[i]; |
---|
1411 | if(actual_entry>0) |
---|
1412 | head_support|=(1<<i); |
---|
1413 | else |
---|
1414 | if(actual_entry[i]<0) |
---|
1415 | tail_support|=(1<<i); |
---|
1416 | } |
---|
1417 | |
---|
1418 | #endif // SUPPORT_VARIABLES_FIRST |
---|
1419 | |
---|
1420 | |
---|
1421 | #ifdef SUPPORT_VARIABLES_LAST |
---|
1422 | |
---|
1423 | for(short i=0;i<size_of_support_vectors;i++) |
---|
1424 | { |
---|
1425 | Integer actual_entry=exponent_vector[_number_of_variables-1-i]; |
---|
1426 | if(actual_entry>0) |
---|
1427 | head_support|=(1<<i); |
---|
1428 | else |
---|
1429 | if(actual_entry<0) |
---|
1430 | tail_support|=(1<<i); |
---|
1431 | } |
---|
1432 | |
---|
1433 | #endif // SUPPORT_VARIABLES_LAST |
---|
1434 | |
---|
1435 | |
---|
1436 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1437 | return TRUE; |
---|
1438 | |
---|
1439 | } |
---|
1440 | |
---|
1441 | |
---|
1442 | |
---|
1443 | |
---|
1444 | BOOLEAN binomial::drop_last_weighted_variable(const term_ordering& w) |
---|
1445 | { |
---|
1446 | _number_of_variables--; |
---|
1447 | // dangerous!! |
---|
1448 | |
---|
1449 | // copy components of interest to save memory |
---|
1450 | // the leading term has to be recomputed!! |
---|
1451 | |
---|
1452 | Integer *aux=exponent_vector; |
---|
1453 | exponent_vector=new Integer[_number_of_variables]; |
---|
1454 | |
---|
1455 | short last_weighted_variable=w.number_of_weighted_variables()-1; |
---|
1456 | aux[last_weighted_variable]=0; |
---|
1457 | // set last component to zero, so it cannot influence the weight |
---|
1458 | |
---|
1459 | if(w.weight(aux)>=0) |
---|
1460 | { |
---|
1461 | for(short i=0;i<last_weighted_variable;i++) |
---|
1462 | exponent_vector[i]=aux[i]; |
---|
1463 | for(short i=last_weighted_variable;i<_number_of_variables;i++) |
---|
1464 | exponent_vector[i]=aux[i+1]; |
---|
1465 | } |
---|
1466 | else |
---|
1467 | { |
---|
1468 | for(short i=0;i<last_weighted_variable;i++) |
---|
1469 | exponent_vector[i]=-aux[i]; |
---|
1470 | for(short i=last_weighted_variable;i<_number_of_variables;i++) |
---|
1471 | exponent_vector[i]=-aux[i+1]; |
---|
1472 | } |
---|
1473 | |
---|
1474 | delete[] aux; |
---|
1475 | |
---|
1476 | |
---|
1477 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1478 | |
---|
1479 | // Recompute head and tail. |
---|
1480 | // Normally, this routine is only called for binomials that do not involve |
---|
1481 | // the variable to be dropped. But if SUPPORT_VARIABLES_LAST is enabled, |
---|
1482 | // the support changes in spite of this. Therefore, the support is |
---|
1483 | // recomputed... For the same reasons as mentionned in the preceeding |
---|
1484 | // routines, the existing support information is not used. |
---|
1485 | |
---|
1486 | head_support=0; |
---|
1487 | tail_support=0; |
---|
1488 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
---|
1489 | if(size_of_support_vectors>_number_of_variables) |
---|
1490 | size_of_support_vectors=_number_of_variables; |
---|
1491 | |
---|
1492 | |
---|
1493 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
1494 | |
---|
1495 | for(short i=0;i<size_of_support_vectors;i++) |
---|
1496 | { |
---|
1497 | Integer actual_entry=exponent_vector[i]; |
---|
1498 | if(actual_entry>0) |
---|
1499 | head_support|=(1<<i); |
---|
1500 | else |
---|
1501 | if(actual_entry<0) |
---|
1502 | tail_support|=(1<<i); |
---|
1503 | } |
---|
1504 | |
---|
1505 | #endif // SUPPORT_VARIABLES_FIRST |
---|
1506 | |
---|
1507 | |
---|
1508 | #ifdef SUPPORT_VARIABLES_LAST |
---|
1509 | |
---|
1510 | for(short i=0;i<size_of_support_vectors;i++) |
---|
1511 | { |
---|
1512 | Integer actual_entry=exponent_vector[_number_of_variables-1-i]; |
---|
1513 | if(actual_entry>0) |
---|
1514 | head_support|=(1<<i); |
---|
1515 | else |
---|
1516 | if(actual_entry<0) |
---|
1517 | tail_support|=(1<<i); |
---|
1518 | } |
---|
1519 | |
---|
1520 | #endif // SUPPORT_VARIABLES_LAST |
---|
1521 | |
---|
1522 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1523 | return TRUE; |
---|
1524 | } |
---|
1525 | |
---|
1526 | |
---|
1527 | |
---|
1528 | |
---|
1529 | int binomial::adapt_to_term_ordering(const term_ordering& w) |
---|
1530 | { |
---|
1531 | |
---|
1532 | if(w.compare_to_zero(exponent_vector)<0) |
---|
1533 | { |
---|
1534 | // then exchange head and tail |
---|
1535 | for(short i=0;i<_number_of_variables;i++) |
---|
1536 | exponent_vector[i]*=(-1); |
---|
1537 | |
---|
1538 | |
---|
1539 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1540 | |
---|
1541 | unsigned long swap=head_support; |
---|
1542 | head_support=tail_support; |
---|
1543 | tail_support=swap; |
---|
1544 | |
---|
1545 | #endif |
---|
1546 | |
---|
1547 | |
---|
1548 | return -1; |
---|
1549 | // binomial changed |
---|
1550 | } |
---|
1551 | |
---|
1552 | else |
---|
1553 | return 1; |
---|
1554 | // binomial unchanged |
---|
1555 | } |
---|
1556 | |
---|
1557 | |
---|
1558 | |
---|
1559 | |
---|
1560 | binomial& binomial::swap_variables(const short& i, const short& j) |
---|
1561 | { |
---|
1562 | |
---|
1563 | |
---|
1564 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1565 | |
---|
1566 | // First adjust head_support and tail_support. |
---|
1567 | |
---|
1568 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
---|
1569 | if(size_of_support_vectors>_number_of_variables) |
---|
1570 | size_of_support_vectors=_number_of_variables; |
---|
1571 | |
---|
1572 | |
---|
1573 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
1574 | |
---|
1575 | if(i<size_of_support_vectors) |
---|
1576 | // else i is no support variable |
---|
1577 | { |
---|
1578 | if(exponent_vector[j]>0) |
---|
1579 | // bit i will be 1 in the new head_support, 0 in the new tail_support |
---|
1580 | { |
---|
1581 | head_support|=(1<<i); |
---|
1582 | // bit i is set to 1 |
---|
1583 | |
---|
1584 | tail_support&=~(1<<i); |
---|
1585 | // bit i is set to 0 |
---|
1586 | // (in the complement ~(1<<i) all bits are 1 except from bit i) |
---|
1587 | } |
---|
1588 | |
---|
1589 | if(exponent_vector[j]==0) |
---|
1590 | // bit i will be 0 in the new head_support, 0 in the new tail_support |
---|
1591 | { |
---|
1592 | head_support&=~(1<<i); |
---|
1593 | // bit i is set to 0 |
---|
1594 | |
---|
1595 | tail_support&=~(1<<i); |
---|
1596 | // bit i is set to 0 |
---|
1597 | } |
---|
1598 | |
---|
1599 | if(exponent_vector[j]<0) |
---|
1600 | // bit i will be 0 in the new head_support, 1 in the new tail_support |
---|
1601 | { |
---|
1602 | head_support&=~(1<<i); |
---|
1603 | // bit i is set to 0 |
---|
1604 | |
---|
1605 | tail_support|=(1<<i); |
---|
1606 | // bit i is set to 1 |
---|
1607 | } |
---|
1608 | } |
---|
1609 | |
---|
1610 | |
---|
1611 | if(j<size_of_support_vectors) |
---|
1612 | // else j is no support variable |
---|
1613 | { |
---|
1614 | if(exponent_vector[i]>0) |
---|
1615 | // bit j will be 1 in the new head_support, 0 in the new tail_support |
---|
1616 | { |
---|
1617 | head_support|=(1<<j); |
---|
1618 | // bit j is set to 1 |
---|
1619 | |
---|
1620 | tail_support&=~(1<<j); |
---|
1621 | // bit j is set to 0 |
---|
1622 | // (in the complement ~(1<<j) all bits are 1 except from bit j) |
---|
1623 | } |
---|
1624 | |
---|
1625 | if(exponent_vector[i]==0) |
---|
1626 | // bit j will be 0 in the new head_support, 0 in the new tail_support |
---|
1627 | { |
---|
1628 | head_support&=~(1<<j); |
---|
1629 | // bit j is set to 0 |
---|
1630 | |
---|
1631 | tail_support&=~(1<<j); |
---|
1632 | // bit j is set to 0 |
---|
1633 | } |
---|
1634 | |
---|
1635 | if(exponent_vector[i]<0) |
---|
1636 | // bit j will be 0 in the new head_support, 1 in the new tail_support |
---|
1637 | { |
---|
1638 | head_support&=~(1<<j); |
---|
1639 | // bit j is set to 0 |
---|
1640 | |
---|
1641 | tail_support|=(1<<j); |
---|
1642 | // bit j is set to 1 |
---|
1643 | } |
---|
1644 | } |
---|
1645 | |
---|
1646 | #endif // SUPPORT_VARIABLES_FIRST |
---|
1647 | |
---|
1648 | |
---|
1649 | #ifdef SUPPORT_VARIABLES_LAST |
---|
1650 | |
---|
1651 | // Using SUPPORT_VARIABLES_LAST, bit k of the support vectors |
---|
1652 | // corresponds to exponent_vector[_number_of_variables-1-k], |
---|
1653 | // hence bit _number_of_variables-1-i to exponent_vector[i]. |
---|
1654 | |
---|
1655 | if(i>=_number_of_variables-size_of_support_vectors) |
---|
1656 | // else i is no support variable |
---|
1657 | { |
---|
1658 | if(exponent_vector[j]>0) |
---|
1659 | // bit _number_of_variables-1-i will be 1 in the new head_support, |
---|
1660 | // 0 in the new tail_support |
---|
1661 | { |
---|
1662 | short k=_number_of_variables-1-i; |
---|
1663 | |
---|
1664 | head_support|=(1<<k); |
---|
1665 | // bit _number_of_variables-1-i is set to 1 |
---|
1666 | |
---|
1667 | tail_support&=~(1<<k); |
---|
1668 | // bit _number_of_variables-1-i is set to 0 |
---|
1669 | // (in the complement ~(1<<(_number_of_variables-1-i)) all bits are 1 |
---|
1670 | // except from bit _number_of_variables-1-i) |
---|
1671 | } |
---|
1672 | |
---|
1673 | if(exponent_vector[j]==0) |
---|
1674 | // bit _number_of_variables-1-i will be 0 in the new head_support, |
---|
1675 | // 0 in the new tail_support |
---|
1676 | { |
---|
1677 | short k=_number_of_variables-1-i; |
---|
1678 | |
---|
1679 | head_support&=~(1<<k); |
---|
1680 | // bit _number_of_variables-1-i is set to 0 |
---|
1681 | |
---|
1682 | tail_support&=~(1<<k); |
---|
1683 | // bit _number_of_variables-1-i is set to 0 |
---|
1684 | } |
---|
1685 | |
---|
1686 | if(exponent_vector[j]<0) |
---|
1687 | // bit _number_of_variables-1-i will be 0 in the new head_support, |
---|
1688 | // 1 in the new tail_support |
---|
1689 | { |
---|
1690 | short k=_number_of_variables-1-i; |
---|
1691 | |
---|
1692 | head_support&=~(1<<k); |
---|
1693 | // bit _number_of_variables-1-i is set to 0 |
---|
1694 | |
---|
1695 | tail_support|=(1<<k); |
---|
1696 | // bit _number_of_variables-1-i is set to 1 |
---|
1697 | } |
---|
1698 | } |
---|
1699 | |
---|
1700 | |
---|
1701 | if(j>=_number_of_variables-size_of_support_vectors) |
---|
1702 | // else j is no support variable |
---|
1703 | { |
---|
1704 | if(exponent_vector[i]>0) |
---|
1705 | // bit _number_of_variables-1-j will be 1 in the new head_support, |
---|
1706 | // 0 in the new tail_support |
---|
1707 | { |
---|
1708 | short k=_number_of_variables-1-j; |
---|
1709 | |
---|
1710 | head_support|=(1<<k); |
---|
1711 | // bit _number_of_variables-1-j is set to 1 |
---|
1712 | |
---|
1713 | tail_support&=~(1<<k); |
---|
1714 | // bit _number_of_variables-1-j is set to 0 |
---|
1715 | // (in the complement ~(1<<(_number_of_variables-1-j)) all bits are 1 |
---|
1716 | // except from bit _number_of_variables-1-j) |
---|
1717 | } |
---|
1718 | |
---|
1719 | if(exponent_vector[i]==0) |
---|
1720 | // bit _number_of_variables-1-j will be 0 in the new head_support, |
---|
1721 | // 0 in the new tail_support |
---|
1722 | { |
---|
1723 | short k=_number_of_variables-1-j; |
---|
1724 | |
---|
1725 | head_support&=~(1<<k); |
---|
1726 | // bit _number_of_variables-1-j is set to 0 |
---|
1727 | |
---|
1728 | tail_support&=~(1<<k); |
---|
1729 | // bit _number_of_variables-1-j is set to 0 |
---|
1730 | } |
---|
1731 | |
---|
1732 | if(exponent_vector[i]<0) |
---|
1733 | // bit _number_of_variables-1-j will be 0 in the new head_support, |
---|
1734 | // 1 in the new tail_support |
---|
1735 | { |
---|
1736 | short k=_number_of_variables-1-j; |
---|
1737 | |
---|
1738 | head_support&=~(1<<k); |
---|
1739 | // bit _number_of_variables-1-j is set to 0 |
---|
1740 | |
---|
1741 | tail_support|=(1<<k); |
---|
1742 | // bit _number_of_variables-1-j is set to 1 |
---|
1743 | } |
---|
1744 | } |
---|
1745 | |
---|
1746 | #endif // SUPPORT_VARIABLES_LAST |
---|
1747 | |
---|
1748 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1749 | |
---|
1750 | |
---|
1751 | // Now swap the components. |
---|
1752 | |
---|
1753 | Integer swap=exponent_vector[j]; |
---|
1754 | exponent_vector[j]=exponent_vector[i]; |
---|
1755 | exponent_vector[i]=swap; |
---|
1756 | |
---|
1757 | return *this; |
---|
1758 | |
---|
1759 | } |
---|
1760 | |
---|
1761 | binomial& binomial::flip_variable(const short& i) |
---|
1762 | { |
---|
1763 | |
---|
1764 | if(exponent_vector[i]==0) |
---|
1765 | // binomial does not involve variable to flip |
---|
1766 | return *this; |
---|
1767 | |
---|
1768 | |
---|
1769 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1770 | |
---|
1771 | // First adjust head_support and tail_support. |
---|
1772 | |
---|
1773 | short size_of_support_vectors=CHAR_BIT*sizeof(unsigned long); |
---|
1774 | if(size_of_support_vectors>_number_of_variables) |
---|
1775 | size_of_support_vectors=_number_of_variables; |
---|
1776 | |
---|
1777 | |
---|
1778 | #ifdef SUPPORT_VARIABLES_FIRST |
---|
1779 | |
---|
1780 | if(i<size_of_support_vectors) |
---|
1781 | // else i is no support variable |
---|
1782 | { |
---|
1783 | if(exponent_vector[i]>0) |
---|
1784 | // variable i will be moved from head to tail |
---|
1785 | { |
---|
1786 | head_support&=~(1<<i); |
---|
1787 | // bit i is set to 0 |
---|
1788 | |
---|
1789 | tail_support|=(1<<i); |
---|
1790 | // bit i is set to 1 |
---|
1791 | } |
---|
1792 | |
---|
1793 | else |
---|
1794 | // variable i will be moved from tail to head |
---|
1795 | // remember that exponent_vector[i]!=0 |
---|
1796 | { |
---|
1797 | tail_support&=~(1<<i); |
---|
1798 | // bit i is set to 0 |
---|
1799 | |
---|
1800 | head_support|=(1<<i); |
---|
1801 | // bit i is set to 1 |
---|
1802 | } |
---|
1803 | } |
---|
1804 | #endif // SUPPORT_VARIABLES_FIRST |
---|
1805 | |
---|
1806 | #ifdef SUPPORT_VARIABLES_LAST |
---|
1807 | |
---|
1808 | // Using SUPPORT_VARIABLES_LAST, bit k of the support vectors |
---|
1809 | // corresponds to exponent_vector[_number_of_variables-1-k], |
---|
1810 | // hence bit _number_of_variables-1-i to exponent_vector[i]. |
---|
1811 | |
---|
1812 | if(i>=_number_of_variables-size_of_support_vectors) |
---|
1813 | // else i is no support variable |
---|
1814 | { |
---|
1815 | if(exponent_vector[i]>0) |
---|
1816 | // variable i will be moved from head to tail |
---|
1817 | { |
---|
1818 | short k=_number_of_variables-1-i; |
---|
1819 | |
---|
1820 | head_support&=~(1<<k); |
---|
1821 | // bit _number_of_variables-1-i is set to 0 |
---|
1822 | |
---|
1823 | tail_support|=(1<<k); |
---|
1824 | // bit _number_of_variables-1-i is set to 1 |
---|
1825 | |
---|
1826 | } |
---|
1827 | |
---|
1828 | else |
---|
1829 | // variable i will be moved from tail to head |
---|
1830 | { |
---|
1831 | short k=_number_of_variables-1-i; |
---|
1832 | |
---|
1833 | tail_support&=~(1<<k); |
---|
1834 | // bit _number_of_variables-1-i is set to 0 |
---|
1835 | |
---|
1836 | head_support|=(1<<k); |
---|
1837 | // bit _number_of_variables-1-i is set to 1 |
---|
1838 | |
---|
1839 | } |
---|
1840 | } |
---|
1841 | #endif // SUPPORT_VARIABLES_LAST |
---|
1842 | |
---|
1843 | |
---|
1844 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1845 | |
---|
1846 | // Now flip the variable. |
---|
1847 | |
---|
1848 | exponent_vector[i]*=-1; |
---|
1849 | return *this; |
---|
1850 | } |
---|
1851 | |
---|
1852 | ////////////////////////// output ///////////////////////////////////////// |
---|
1853 | |
---|
1854 | void binomial::print() const |
---|
1855 | { |
---|
1856 | printf("("); |
---|
1857 | for(short i=0;i<_number_of_variables-1;i++) |
---|
1858 | printf("%6d,",exponent_vector[i]); |
---|
1859 | printf("%6d)\n",exponent_vector[_number_of_variables-1]); |
---|
1860 | } |
---|
1861 | |
---|
1862 | void binomial::print_all() const |
---|
1863 | { |
---|
1864 | print(); |
---|
1865 | |
---|
1866 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1867 | |
---|
1868 | printf("head: %ld, tail %ld\n",head_support,tail_support); |
---|
1869 | |
---|
1870 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1871 | } |
---|
1872 | |
---|
1873 | void binomial::print(FILE* output) const |
---|
1874 | { |
---|
1875 | fprintf(output,"("); |
---|
1876 | for(short i=0;i<_number_of_variables-1;i++) |
---|
1877 | fprintf(output,"%6d,",exponent_vector[i]); |
---|
1878 | fprintf(output,"%6d)\n",exponent_vector[_number_of_variables-1]); |
---|
1879 | } |
---|
1880 | |
---|
1881 | void binomial::print_all(FILE* output) const |
---|
1882 | { |
---|
1883 | print(output); |
---|
1884 | |
---|
1885 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1886 | |
---|
1887 | fprintf(output,"head: %ld, tail %ld\n",head_support,tail_support); |
---|
1888 | |
---|
1889 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1890 | } |
---|
1891 | |
---|
1892 | void binomial::print(ofstream& output) const |
---|
1893 | { |
---|
1894 | output<<"("; |
---|
1895 | for(short i=0;i<_number_of_variables-1;i++) |
---|
1896 | output<<setw(6)<<exponent_vector[i]<<","; |
---|
1897 | output<<setw(6)<<exponent_vector[_number_of_variables-1]<<")"<<endl; |
---|
1898 | } |
---|
1899 | |
---|
1900 | void binomial::print_all(ofstream& output) const |
---|
1901 | { |
---|
1902 | print(output); |
---|
1903 | |
---|
1904 | #ifdef SUPPORT_DRIVEN_METHODS |
---|
1905 | |
---|
1906 | output<<"head: "<<setw(16)<<head_support<<", tail: "<<setw(16) |
---|
1907 | <<tail_support<<endl; |
---|
1908 | |
---|
1909 | #endif // SUPPORT_DRIVEN_METHODS |
---|
1910 | } |
---|
1911 | |
---|
1912 | void binomial::format_print(ofstream& output) const |
---|
1913 | { |
---|
1914 | for(short i=0;i<_number_of_variables;i++) |
---|
1915 | output<<setw(6)<<exponent_vector[i]; |
---|
1916 | output<<endl; |
---|
1917 | } |
---|
1918 | |
---|
1919 | #endif // BINOMIAL_CC |
---|