Singular Manual: testLift

| #### 7.10.4.12 testLift Procedure from library `freegb.lib` (see freegb_lib). Usage: testLift(M,T); module M, matrix T Return: module Purpose: assembles the result of the lift procedure Assume: T is the lift matrix of a submodule of M Note: the inverse of the lift procedure Example:
    LIB "freegb.lib";
    ring r = 0,(x,y),(c,Dp);
    ring R = freeAlgebra(r, 7, 2);
    ideal I = std(x*y*x + 1);
    print(matrix(I)); // finite two-sided Groebner basis
    ==> x*y-y*x,y*x*x+1
    ideal SI = x*I[1]*y + y*x*I[2], I[1]*y*x + I[2]*y;
    matrix T = lift(I, SI); // T is the lifting matrix of SI wrt I
    print(T); //
    ==> y*ncgen(1)*x*x+x*ncgen(1)*y,y*x*ncgen(1)+y*ncgen(1)*x+ncgen(1)*y*x,
    ==> y*ncgen(2)*x,               y*ncgen(2)
    print(matrix(SI)); // the original generators of SI as a matrix
    ==> y*x*y*x*x+x*x*y*y-x*y*x*y+y*x,x*y*y*x+y*x*x*y-y*x*y*x+y
    print(matrix(testLift(I,T))); // and the result of testLift
    ==> y*x*y*x*x+x*x*y*y-x*y*x*y+y*x,x*y*y*x+y*x*x*y-y*x*y*x+y

User manual for Singular version 4-2-1p3, 2021, generated by texi2html.