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GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it

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<?xml version="1.0" encoding="UTF-8"?>
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<!-- This is an automatically generated file. -->
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<Chapter Label="Chapter_4ti2_functions">
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<Heading>4ti2 functions</Heading>
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<Section Label="Chapter_4ti2_functions_Section_Groebner">
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<Heading>Groebner</Heading>
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These are wrappers of some use cases of 4ti2s groebner command.
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<ManSection>
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<Func Arg="matrix[,ordering]" Name="4ti2Interface_groebner_matrix" />
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<Returns>A list of vectors
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</Returns>
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<Description>
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This launches the 4ti2 groebner command with the
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argument as matrix input. The output will be the
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the Groebner basis of the binomial ideal
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generated by the left kernel of the input matrix.
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Note that this is different from 4ti2's convention
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which takes the right kernel.
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It returns the output of the groebner command
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as a list of lists.
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The second argument can be a vector to specify a
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monomial ordering, in the way that x^m > x^n if
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ordering*m > ordering*n
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</Description>
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</ManSection>
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<ManSection>
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<Func Arg="basis[,ordering]" Name="4ti2Interface_groebner_basis" />
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<Returns>A list of vectors
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</Returns>
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<Description>
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This launches the 4ti2 groebner command with the
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argument as matrix input.
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The outpur will be the Groebner basis of the binomial
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ideal generated by the rows of the input matrix.
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It returns the output of the groebner command
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as a list of lists.
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The second argument is like before.
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</Description>
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</ManSection>
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<#Include Label="Groebner1">
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</Section>
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<Section Label="Chapter_4ti2_functions_Section_Hilbert">
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<Heading>Hilbert</Heading>
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These are wrappers of some use cases of 4ti2s hilbert command.
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<ManSection Label="for_inequalities">
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<Func Arg="A" Name="4ti2Interface_hilbert_inequalities" />
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<Func Arg="A" Name="4ti2Interface_hilbert_inequalities_in_positive_orthant" />
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<Returns>a list of vectors
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</Returns>
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<Description>
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This function produces the hilbert basis of the cone C given
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by <A>A</A>x >= 0 for all x in C. For the second function also
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x >= 0 is assumed.
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<P/>
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</Description>
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</ManSection>
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<ManSection>
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<Func Arg="A" Name="4ti2Interface_hilbert_equalities_in_positive_orthant" />
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<Returns>a list of vectors
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</Returns>
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<Description>
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This function produces the hilbert basis of the cone C given by
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the equations <A>A</A>x = 0 in the positive orthant of the coordinate system.
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</Description>
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</ManSection>
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<ManSection Label="for_equalities_and_inequalities">
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<Func Arg="A, B" Name="4ti2Interface_hilbert_equalities_and_inequalities" />
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<Func Arg="A, B" Name="4ti2Interface_hilbert_equalities_and_inequalities_in_positive_orthant" />
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<Returns>a list of vectors
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</Returns>
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<Description>
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This function produces the hilbert basis of the cone C given by
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the equations <A>A</A>x = 0 and the inequations <A>B</A>x >= 0.
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For the second function x>=0 is assumed.
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<P/>
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</Description>
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</ManSection>
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<#Include Label="HilbertBasis">
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<#Include Label="HilbertBasis2">
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</Section>
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<Section Label="Chapter_4ti2_functions_Section_ZSolve">
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<Heading>ZSolve</Heading>
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<ManSection Label="zsolve">
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<Func Arg="eqs,eqs_rhs,ineqs,ineqs_rhs[,signs]" Name="4ti2Interface_zsolve_equalities_and_inequalities" />
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<Func Arg="eqs,eqs_rhs,ineqs,ineqs_rhs" Name="4ti2Interface_zsolve_equalities_and_inequalities_in_positive_orthant" />
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<Returns>a list of three matrices
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</Returns>
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<Description>
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This function produces a basis of the system <A>eqs</A> = <A>eqs_rhs</A>
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and <A>ineqs</A> >= <A>ineqs_rhs</A>. It outputs a list containing three matrices.
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The first one is a list of points in a polytope, the second is the hilbert basis
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of a cone. The set of solutions is then the minkowski sum of the polytope
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generated by the points in the first list and the cone generated by the hilbert
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basis in the second matrix. The third one is the free part of the solution polyhedron.
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The optional argument <A>signs</A> must be a list of zeros and ones which length is
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the number of variables. If the ith entry is one, the ith variable must be >= 0.
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If the entry is 0, the number is arbitraty. Default is all zero.
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It is also possible to set the option precision to 32, 64 or gmp.
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The default, if no option is given, 32 is used.
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Please note that a higher precision leads to slower computation.
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For the second function xi >= 0 for all variables is assumed.
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</Description>
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</ManSection>
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</Section>
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<Section Label="Chapter_4ti2_functions_Section_Graver">
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<Heading>Graver</Heading>
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<ManSection Label="graver">
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<Func Arg="eqs[,signs]" Name="4ti2Interface_graver_equalities" />
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<Func Arg="eqs" Name="4ti2Interface_graver_equalities_in_positive_orthant" />
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<Returns>a matrix
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</Returns>
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<Description>
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This calls the function graver with the equalities <A>eqs</A> = 0.
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It outputs one list containing the
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graver basis of the system.
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the optional argument <A>signs</A> is used like in zsolve.
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The second command assumes <M>x_i \geq 0</M>.
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</Description>
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</ManSection>
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</Section>
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</Chapter>
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