Changeset 75f460 in git for IntegerProgramming/toric_ideal.hlp
- Timestamp:
- Dec 16, 2014, 3:43:21 PM (9 years ago)
- Branches:
- (u'spielwiese', 'fe61d9c35bf7c61f2b6cbf1b56e25e2f08d536cc')
- Children:
- fce947c9e6c3e8c6d5a622c7f6b0d724580993cc
- Parents:
- a2e4470c6e9a666de8ab7b706370c15e13092f76
- File:
-
- 1 edited
Legend:
- Unmodified
- Added
- Removed
-
IntegerProgramming/toric_ideal.hlp
ra2e447 r75f460 1 USAGE: toric_ideal [options] matrix_file 2 3 4 1 USAGE: toric_ideal [options] matrix_file 2 3 4 5 5 DESCRIPTION: 6 6 7 7 toric_ideal is a program for computing the toric ideal of a matrix A. 8 8 This ideal is always given by the reduced Groebner basis with respect 9 9 to a given term ordering which is computed via BuchbergerŽs 10 algorithm. 10 algorithm. 11 11 For this purpose, we can use six different algorithms: 12 12 The algorithm of Conti/Traverso (ct) computes the toric ideal of an 13 13 extended matrix. This ideal can be used later for solving integer 14 14 programming problems for given right hand vectors. By eliminating 15 auxiliary variables, we can get the toric ideal of the original matrix 15 auxiliary variables, we can get the toric ideal of the original matrix 16 16 from it. The same is true for the "positive" variant of the 17 17 Conti-Traverso-algorithm (pct) which can only be applied if A has … … 23 23 are the algorithms of Pottier (pt), Bigatti/La Scala/Robbiano (blr), 24 24 Hosten/Sturmfels (hs) and Di Biase/Urbanke (du). The last two seem to 25 be the fastest in the actual implementation. 26 27 28 25 be the fastest in the actual implementation. 26 27 28 29 29 FILE FORMAT: 30 30 31 31 The input file has to be a MATRIX file. toric_ideal produces a 32 GROEBNER file named like the MATRIX file with extensions replaced by 33 34 .GB.<alg> 35 32 GROEBNER file named like the MATRIX file with extensions replaced by 33 34 .GB.<alg> 35 36 36 where GB stands for GROEBNER and <alg> is the abbreviation for the 37 37 used algorithm as above. 38 38 39 39 A MATRIX file should look as follows: 40 41 42 MATRIX 43 40 41 42 MATRIX 43 44 44 columns: 45 45 <number of columns> 46 46 47 47 cost vector: 48 48 <coefficients of the cost vector> 49 49 50 50 rows: 51 51 <number of rows> 52 52 53 53 matrix: 54 54 <matrix coefficients> 55 56 positive row space vector: 57 <coefficients of row space vector> 58 59 60 The last two lines are only needed when toric_ideal is called with the 55 56 positive row space vector: 57 <coefficients of row space vector> 58 59 60 The last two lines are only needed when toric_ideal is called with the 61 61 algorithms of Hosten/Sturmfels or Bigatti/La Scala/Robbiano, i.e. the 62 options 63 62 options 63 64 64 -alg hs 65 65 or 66 66 -alg blr 67 68 The other algorithms ignore these lines. 69 67 68 The other algorithms ignore these lines. 69 70 70 Example: 71 72 71 72 73 73 MATRIX 74 74 75 75 columns: 76 76 3 77 77 78 78 cost vector: 79 79 1 1 1 80 80 81 81 rows: 82 82 2 83 83 84 84 matrix: 85 85 1 2 3 86 86 4 5 6 87 87 88 88 positive row space vector: 89 89 1 2 3 90 91 90 91 92 92 A GROEBNER file looks as follows: 93 94 95 GROEBNER 96 93 94 95 GROEBNER 96 97 97 computed with algorithm: 98 98 <algorithm name abbreviation> (* abbreviations as above *) 99 from file(s): (* the following four lines are 99 from file(s): (* the following four lines are 100 100 <name of respective MATRIX file> optional *) 101 computation time: 102 <computation time in seconds> 103 101 computation time: 102 <computation time in seconds> 103 104 104 term ordering: 105 105 elimination block … … 109 109 weighted block 110 110 <number of weighted variables> 111 <W_LEX / W_REV_LEX (* number of weighted variables 111 <W_LEX / W_REV_LEX (* number of weighted variables 112 112 / W_DEG_LEX / W_DEG_REV_LEX> should always be >0 *) 113 113 <weight_vector> 114 114 115 115 size: 116 116 <number of elements> 117 117 118 118 Groebner basis: 119 <basis elements> 120 121 <settings for the Buchberger 122 algorithm and compiler settings> (* optional *) 123 124 119 <basis elements> 120 121 <settings for the Buchberger 122 algorithm and compiler settings> (* optional *) 123 124 125 125 The Groebner basis consists always of binomials of the form x^a - x^b 126 126 where x^a and x^b are relatively prime. Such a binomial can be 127 represented by the vector a-b. The basis elements in the GROEBNER file 127 represented by the vector a-b. The basis elements in the GROEBNER file 128 128 are given by the coefficients of this vector representation. 129 129 The settings for BuchbergerŽs algorithm and the compiler flags are 130 produced when the GROEBNER file is generated by a call of toric_ideal 130 produced when the GROEBNER file is generated by a call of toric_ideal 131 131 with the verbose output option 132 133 -v, --verbose 134 132 133 -v, --verbose 134 135 135 Example (not belonging to the example above): 136 137 136 137 138 138 GROEBNER 139 139 140 140 computed with algorithm: 141 141 du 142 143 term ordering: 142 143 term ordering: 144 144 elimination block: 145 145 0 … … 148 148 W_LEX 149 149 1 2 3 150 150 151 151 size: 152 152 1 153 153 154 154 Groebner basis: 155 2 3 -2 (* x^2 * y^3 - z^2 *) 156 157 158 159 OPTIONS: 160 161 -alg <alg>, 155 2 3 -2 (* x^2 * y^3 - z^2 *) 156 157 158 159 OPTIONS: 160 161 -alg <alg>, 162 162 --algorithm <alg> algorithm to use for computing the toric 163 ideal; <alg> may be 163 ideal; <alg> may be 164 164 ct for Conti/Traverso, 165 165 pct for the positive Conti/Traverso, … … 169 169 du for Di Biase/Urbanke, 170 170 blr for Bigatti-LaScal-Robbiano. 171 171 172 172 -p <number> percentage of new generators to cause an 173 autoreduction during BuchbergerŽs algorithm; 173 autoreduction during BuchbergerŽs algorithm; 174 174 <number> may be an arbitrary float, a 175 175 negative value allows no intermediate 176 176 autoreductions 177 default is 178 -p 12.0 177 default is 178 -p 12.0 179 179 180 180 -S [RP] [M] [B] [M] [2] criteria to use in BuchbergerŽs algorithm … … 185 185 B Gebauer-Moeller criterion B 186 186 2 BuchbergerŽs second criterion 187 default is 188 -S RP M B 189 190 -v, 191 --verbose verbose output mode; writes the settings for 187 default is 188 -S RP M B 189 190 -v, 191 --verbose verbose output mode; writes the settings for 192 192 BuchbergerŽs algorithm and the compiler 193 flags into the output GROEBNER file 194 195 -V <number>, 193 flags into the output GROEBNER file 194 195 -V <number>, 196 196 --version <number> version of BuchbergerŽs algorithm to use; 197 197 <number> may be 1, 1a, 2 or 3 198 198 default is 199 -V 1 200 201 199 -V 1 200 201
Note: See TracChangeset
for help on using the changeset viewer.