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NAME
     zgetf2 - compute an LU factorization  of  a  general  m-by-n
     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, * )



     #include <sunperf.h>

     void zgetf2(int m, int n, doublecomplex *za,  int  lda,  int
               *ipivot, int *info) ;

PURPOSE
     ZGETF2 computes an LU  factorization  of  a  general  m-by-n
     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 right-looking Level 2 BLAS version of the  algo-
     rithm.


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 k-th argument had an  ille-
               gal value
               > 0: if INFO = k, U(k,k) is exactly zero. The fac-
               torization 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.

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