How can I find the dimensions of a matrix in Python. Len(A) returns only one variable. Edit: Hi Thanks. close = dataobj.get_data(timestamps, symbols, closefield) Is (I assume) generating a matrix of integers (less likely strings). I need to find the size of that matrix, so I can run some tests without having to iterate through all of the elements. As far as the data type goes, I assume it's an array of arrays (or list of lists).