LIB "tst.lib"; tst_init();
LIB "linalg.lib";
ring r=0,(x),dp;
matrix A[5][4]=1,3,-1,4,2,5,-1,3,1,3,-1,4,0,4,-3,1,-3,1,-5,-2;
print(A);
list Z=gaussred(A);   //construct P,U,S s.t. P*A=U*S
print(Z[1]);          //P
print(Z[2]);          //U
print(Z[3]);          //S
print(Z[4]);          //rank
print(Z[1]*A);        //P*A
print(Z[2]*Z[3]);     //U*S
tst_status(1);$