zgetrs(3F)

NAME
     ZGETRS - solve a system of linear equations  A * X = B, A**T * X = B, or
     A**H * X = B with a general N-by-N matrix A using the LU factorization
     computed by ZGETRF

SYNOPSIS
     SUBROUTINE ZGETRS( TRANS, N, NRHS, A, LDA, IPIV, B, LDB, INFO )

         CHARACTER      TRANS

         INTEGER        INFO, LDA, LDB, N, NRHS

         INTEGER        IPIV( * )

         COMPLEX*16     A( LDA, * ), B( LDB, * )

PURPOSE
     ZGETRS solves a system of linear equations
        A * X = B,  A**T * X = B,  or  A**H * X = B with a general N-by-N
     matrix A using the LU factorization computed by ZGETRF.


ARGUMENTS
     TRANS   (input) CHARACTER*1
             Specifies the form of the system of equations:
             = 'N':  A * X = B     (No transpose)
             = 'T':  A**T * X = B  (Transpose)
             = 'C':  A**H * X = B  (Conjugate transpose)

     N       (input) INTEGER
             The order of the matrix A.  N >= 0.

     NRHS    (input) INTEGER
             The number of right hand sides, i.e., the number of columns of
             the matrix B.  NRHS >= 0.

     A       (input) COMPLEX*16 array, dimension (LDA,N)
             The factors L and U from the factorization A = P*L*U as computed
             by ZGETRF.

     LDA     (input) INTEGER
             The leading dimension of the array A.  LDA >= max(1,N).

     IPIV    (input) INTEGER array, dimension (N)
             The pivot indices from ZGETRF; for 1<=i<=N, row i of the matrix
             was interchanged with row IPIV(i).

     B       (input/output) COMPLEX*16 array, dimension (LDB,NRHS)
             On entry, the right hand side matrix B.  On exit, the solution
             matrix X.
     LDB     (input) INTEGER
             The leading dimension of the array B.  LDB >= max(1,N).

     INFO    (output) INTEGER
             = 0:  successful exit
             < 0:  if INFO = -i, the i-th argument had an illegal value