Singular Manual: grrndmap

| #### D.15.20.25 grrndmap Procedure from library `gradedModules.lib` (see gradedModules_lib). Usage: grrndmap(S,D), graded objects S and D Return: graded object Purpose: construct a random 0-deg graded homomorphism src(S) -> src(D) Example:
    LIB "gradedModules.lib";
    ring r=32003,(x,y,z),dp;
    module D=grobj(module([y,0,z],[x2+y2,z,0]),intvec(0,1,0));
    grview(D);
    ==> Graded homomorphism: r + r(-1) + r <- r(-1) + r(-2), given by a matrix, w\
       ith degrees:
    ==>      ..1 ..2 ....
    ==>      --- --- +...
    ==>   0 :  1   2 |..1
    ==>   1 :  -   1 |..2
    ==>   0 :  1   - |..3
    ==>      === ===
    ==>        1   2
    module S=grobj(module([x,0,y],[xy,zy+x2,0]),intvec(0,0,0));
    grview(S);
    ==> Graded homomorphism: r^3 <- r(-1) + r(-2), given by a matrix, with degree\
       s:
    ==>      ..1 ..2 ....
    ==>      --- --- +...
    ==>   0 :  1   2 |..1
    ==>   0 :  -   2 |..2
    ==>   0 :  1   - |..3
    ==>      === ===
    ==>        1   2
    def H=grrndmap(D,S);
    grview(H);
    ==> Graded homomorphism: r(-1) + r(-2) <- r(-1) + r(-2), given by a square ma\
       trix, with degrees:
    ==>      ..1 ..2 ....
    ==>      --- --- +...
    ==>   1 :  0   1 |..1
    ==>   2 :  -   0 |..2
    ==>      === ===
    ==>        1   2

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