Revision history [back]

Suppose B is a finite collection of distinct square matrices of nth order.

And , A a subcollection of B.

I want unique combinations of four distinct elements -three from A and one from B.

I tried this

X=Combinations(A,3)
Y=Combinations(B,1)
for i in range(len(X)):
    for j in range(3):
        for k in range(len(Y)):
            if ((X[i])[j])!=(Y[k]):
                show(X[i]+Y[k])

I know problem is with my "if" command.

My question is how to change the “if” command so that none of the matrices in X[i] equals Y[k], so that we get distinct matrices in a combination.

Further, how to get unique combinations.

Thanks.