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Python Introducing Lists Using Lists Multidimensional Lists

Posted by Charan sai
Charan sai
Courses Plus Student 797 Points

How to multiply two multidimensional lists like multiplication of matrices??

I need to store two 3*3 matrices in two variables each

If I want to multiply them what should I do??

1 Answer

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

I'm not sure what you mean by "two variables each". How do you use two variables to store a 3x3 matrix?

But assuming they were stored in one variable each, named "X" and "Y", here's one way:

result = [[sum(a*b for a,b in zip(X_row,Y_col)) for Y_col in zip(*Y)] for X_row in X]

There's also a popular library called "NumPy" (taught in courses here) that would have methods for this.

I hope I didn't just do your homework! :see_no_evil: