Singular Manual: minimalAfaces

| #### D.15.18.4 minimalAfaces Procedure from library `gitfan.lib` (see gitfan_lib). Usage: minimalAfaces(listOfAfaces); listOfAfaces: list Purpose: Returns a list of all minimal a-faces. Note that listOfAfaces must only contain afaces which project to full dimension. Return: a list of intvecs 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));
    size(AF);
    ==> 81
    AF=fullDimImages(AF,Q);
    size(AF);
    ==> 36
    AF=minimalAfaces(AF);
    size(AF);
    ==> 25

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