CGETF2  -  compute an LU factorization of a general m-by-n
       matrix A using partial pivoting with row interchanges


SYNOPSIS

       SUBROUTINE CGETF2( M, N, A, LDA, IPIV, INFO )

           INTEGER        INFO, LDA, M, N

           INTEGER        IPIV( * )

           COMPLEX        A( LDA, * )


PURPOSE

       CGETF2 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
       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 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



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