
ZGETF2(l) ) ZGETF2(l)
NAME
ZGETF2  compute an LU factorization of a general mbyn matrix A using partial pivoting
with row interchanges
SYNOPSIS
SUBROUTINE ZGETF2( M, N, A, LDA, IPIV, INFO )
INTEGER INFO, LDA, M, N
INTEGER IPIV( * )
COMPLEX*16 A( LDA, * )
PURPOSE
ZGETF2 computes an LU factorization of a general mbyn matrix A using partial pivoting
with row interchanges. The factorization has the form
A = P * L * U
where P is a permutation matrix, L is lower triangular with unit diagonal elements (lower
trapezoidal if m > n), and U is upper triangular (upper trapezoidal if m < n).
This is the rightlooking Level 2 BLAS version of the algorithm.
ARGUMENTS
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0.
A (input/output) COMPLEX*16 array, dimension (LDA,N)
On entry, the m by n matrix to be factored. On exit, the factors L and U from the
factorization A = P*L*U; the unit diagonal elements of L are not stored.
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,M).
IPIV (output) INTEGER array, dimension (min(M,N))
The pivot indices; for 1 <= i <= min(M,N), row i of the matrix was interchanged
with row IPIV(i).
INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = k, the kth argument had an illegal value
> 0: if INFO = k, U(k,k) is exactly zero. The factorization has been completed,
but the factor U is exactly singular, and division by zero will occur if it is
used to solve a system of equations.
LAPACK version 3.0 15 June 2000 ZGETF2(l) 
