Singular Manual: hashesToFan

| #### D.13.3.29 hashesToFan Procedure from library `gitfan.lib` (see gitfan_lib). Usage: hashesToFan(hashes, OC): hashes list of bigint, OC list of cones. Assume: the elements of OC are the orbit cones used in the hash representation of the GIT cones. Return: a fan, with maximal cones the intersections of the cones in OC according to the binary representation of the hashes. Example:
    LIB "gitfan.lib";
    setcores(4);
    ==> 4
    ring R = 0,T(1..10),wp(1,1,1,1,1,1,1,1,1,1);
    ideal J =
    T(5)*T(10)-T(6)*T(9)+T(7)*T(8),
    T(1)*T(9)-T(2)*T(7)+T(4)*T(5),
    T(1)*T(8)-T(2)*T(6)+T(3)*T(5),
    T(1)*T(10)-T(3)*T(7)+T(4)*T(6),
    T(2)*T(10)-T(3)*T(9)+T(4)*T(8);
    intmat Q[5][10] =
    1, 1, 1, 1, 0, 0, 0, 0, 0, 0,
    1, 0, 0, 0, 1, 1, 1, 0, 0, 0,
    0, 1, 1, 0, 0, 0, -1, 1, 0, 0,
    0, 1, 0, 1, 0, -1, 0, 0, 1, 0,
    0, 0, 1, 1, -1, 0, 0, 0, 0, 1;
    list AF= afaces(J,nrows(Q));
    AF=fullDimImages(AF,Q);
    AF = minimalAfaces(AF);
    list OC = orbitCones(AF,Q);
    cone Qgamma = coneViaPoints(transpose(Q));
    list GIT = GITfanParallel(OC,Q,Qgamma);
    fan Sigma = hashesToFan(GIT,OC);

User manual for Singular version 4.3.2, 2023, generated by texi2html.