Problem
Write function that takes a matrix A and determines if there is a full set of pivots. Specifically, if A is a square matrix of size nxn, determine if there are n (non-zero) pivots). If A is rectangular, do not declare an error. Instead if A is mxn, output if the number of pivots equals min(m,n). This means that the rectangular matrix has a pivot in every row (if m <=n ) and a pivot in every col (if m >=n).