SRC/ztrtrs.f(3)            Library Functions Manual            SRC/ztrtrs.f(3)

NAME
       SRC/ztrtrs.f

SYNOPSIS
   Functions/Subroutines
       subroutine ztrtrs (uplo, trans, diag, n, nrhs, a, lda, b, ldb, info)
           ZTRTRS

Function/Subroutine Documentation
   subroutine ztrtrs (character uplo, character trans, character diag, integer
       n, integer nrhs, complex*16, dimension( lda, * ) a, integer lda,
       complex*16, dimension( ldb, * ) b, integer ldb, integer info)
       ZTRTRS

       Purpose:


            ZTRTRS solves a triangular system of the form

               A * X = B,  A**T * X = B,  or  A**H * X = B,

            where A is a triangular matrix of order N, and B is an N-by-NRHS
            matrix.  A check is made to verify that A is nonsingular.

       Parameters
           UPLO

                     UPLO is CHARACTER*1
                     = 'U':  A is upper triangular;
                     = 'L':  A is lower triangular.

           TRANS

                     TRANS is 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)

           DIAG

                     DIAG is CHARACTER*1
                     = 'N':  A is non-unit triangular;
                     = 'U':  A is unit triangular.

           N

                     N is INTEGER
                     The order of the matrix A.  N >= 0.

           NRHS

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

           A

                     A is COMPLEX*16 array, dimension (LDA,N)
                     The triangular matrix A.  If UPLO = 'U', the leading N-by-N
                     upper triangular part of the array A contains the upper
                     triangular matrix, and the strictly lower triangular part of
                     A is not referenced.  If UPLO = 'L', the leading N-by-N lower
                     triangular part of the array A contains the lower triangular
                     matrix, and the strictly upper triangular part of A is not
                     referenced.  If DIAG = 'U', the diagonal elements of A are
                     also not referenced and are assumed to be 1.

           LDA

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

           B

                     B is COMPLEX*16 array, dimension (LDB,NRHS)
                     On entry, the right hand side matrix B.
                     On exit, if INFO = 0, the solution matrix X.

           LDB

                     LDB is INTEGER
                     The leading dimension of the array B.  LDB >= max(1,N).

           INFO

                     INFO is INTEGER
                     = 0:  successful exit
                     < 0: if INFO = -i, the i-th argument had an illegal value
                     > 0: if INFO = i, the i-th diagonal element of A is zero,
                          indicating that the matrix is singular and the solutions
                          X have not been computed.

       Author
           Univ. of Tennessee

           Univ. of California Berkeley

           Univ. of Colorado Denver

           NAG Ltd.

       Definition at line 138 of file ztrtrs.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

LAPACK                          Version 3.12.0                 SRC/ztrtrs.f(3)