LUfact

Usage: lu(<matrix>)
Computes an LU factorization of a general M-by-N matrix using partial pivoting with row interchanges. Factorization has the form A = P*L*U.On exit, the input matrix is comprised of the factors L and U from the factorization A = P*L*U.
Returns an integer vector. The row i of A was interchanged with row IPIV(i).
Ex:lu([1,2;3,4])
Uses the LAPACK function getrf.
See:http://www.osl.iu.edu/research/mtl/doc/getrfLapackMatrixVectorInt.html