LIB "linalg.lib";
ring r=0,(x),dp;
matrix A[10][10]=random(2,10,10)+unitmat(10)*x;
print(A);
==> x+2,-1, 2, 0,  -1, 1, 1,  2,  -1, 1, 
==> 2,  x-1,-1,2,  -1, 1, 1,  2,  1,  0, 
==> -2, 2,  x, 1,  2,  1, -1, -2, -2, 2, 
==> 0,  -1, -1,x+2,0,  -1,1,  0,  -1, 0, 
==> 0,  1,  -2,0,  x+2,1, 1,  -2, 2,  1, 
==> 2,  -2, 0, -2, -1, x, -2, 1,  -2, -2,
==> -1, 2,  2, 1,  1,  -2,x+1,-1, -2, -2,
==> 1,  1,  -1,2,  -2, -1,2,  x+1,0,  1, 
==> -2, 0,  1, 2,  1,  -2,-2, 1,  x+1,0, 
==> 1,  2,  1, 2,  0,  1, -1, 1,  -1, x-1
det_B(A);
==> x10+7x9+7x8-39x7-290x6-1777x5-3646x4+3725x3-5511x2-34811x-13241