text: *> \brief \b CTRSM
  *
  *  =========== DOCUMENTATION ===========
  *
  * Online html documentation available at
  *            http://www.netlib.org/lapack/explore-html/
  *
  *  Definition:
  *  ===========
  *
  *       SUBROUTINE CTRSM(SIDE,UPLO,TRANSA,DIAG,M,N,ALPHA,A,LDA,B,LDB)
  *
  *       .. Scalar Arguments ..
  *       COMPLEX ALPHA
  *       INTEGER LDA,LDB,M,N
  *       CHARACTER DIAG,SIDE,TRANSA,UPLO
  *       ..
  *       .. Array Arguments ..
  *       COMPLEX A(LDA,*),B(LDB,*)
  *       ..
  *
  *
  *> \par Purpose:
  *  =============
  *>
  *> \verbatim
  *>
  *> CTRSM  solves one of the matrix equations
  *>
  *>    op( A )*X = alpha*B,   or   X*op( A ) = alpha*B,
  *>
  *> where alpha is a scalar, X and B are m by n matrices, A is a unit, or
  *> non-unit,  upper or lower triangular matrix  and  op( A )  is one  of
  *>
  *>    op( A ) = A   or   op( A ) = A**T   or   op( A ) = A**H.
  *>
  *> The matrix X is overwritten on B.
  *> \endverbatim
  *
  *  Arguments:
  *  ==========
  *
  *> \param[in] SIDE
  *> \verbatim
  *>          SIDE is CHARACTER*1
  *>           On entry, SIDE specifies whether op( A ) appears on the left
  *>           or right of X as follows:
  *>
  *>              SIDE = 'L' or 'l'   op( A )*X = alpha*B.
  *>
  *>              SIDE = 'R' or 'r'   X*op( A ) = alpha*B.
  *> \endverbatim
  *>
  *> \param[in] UPLO
  *> \verbatim
  *>          UPLO is CHARACTER*1
  *>           On entry, UPLO specifies whether the matrix A is an upper or
  *>           lower triangular matrix as follows:
  *>
  *>              UPLO = 'U' or 'u'   A is an upper triangular matrix.
  *>
  *>              UPLO = 'L' or 'l'   A is a lower triangular matrix.
  *> \endverbatim
  *>
  *> \param[in] TRANSA
  *> \verbatim
  *>          TRANSA is CHARACTER*1
  *>           On entry, TRANSA specifies the form of op( A ) to be used in
  *>           the matrix multiplication as follows:
  *>
  *>              TRANSA = 'N' or 'n'   op( A ) = A.
  *>
  *>              TRANSA = 'T' or 't'   op( A ) = A**T.
  *>
  *>              TRANSA = 'C' or 'c'   op( A ) = A**H.
  *> \endverbatim
  *>
  *> \param[in] DIAG
  *> \verbatim
  *>          DIAG is CHARACTER*1
  *>           On entry, DIAG specifies whether or not A is unit triangular
  *>           as follows:
  *>
  *>              DIAG = 'U' or 'u'   A is assumed to be unit triangular.
  *>
  *>              DIAG = 'N' or 'n'   A is not assumed to be unit
  *>                                  triangular.
  *> \endverbatim
  *>
  *> \param[in] M
  *> \verbatim
  *>          M is INTEGER
  *>           On entry, M specifies the number of rows of B. M must be at
  *>           least zero.
  *> \endverbatim
  *>
  *> \param[in] N
  *> \verbatim
  *>          N is INTEGER
  *>           On entry, N specifies the number of columns of B.  N must be
  *>           at least zero.
  *> \endverbatim
  *>
  *> \param[in] ALPHA
  *> \verbatim
  *>          ALPHA is COMPLEX
  *>           On entry,  ALPHA specifies the scalar  alpha. When  alpha is
  *>           zero then  A is not referenced and  B need not be set before
  *>           entry.
  *> \endverbatim
  *>
  *> \param[in] A
  *> \verbatim
  *>          A is COMPLEX array, dimension ( LDA, k ),
  *>           where k is m when SIDE = 'L' or 'l'
  *>             and k is n when SIDE = 'R' or 'r'.
  *>           Before entry  with  UPLO = 'U' or 'u',  the  leading  k by k
  *>           upper triangular part of the array  A must contain the upper
  *>           triangular matrix  and the strictly lower triangular part of
  *>           A is not referenced.
  *>           Before entry  with  UPLO = 'L' or 'l',  the  leading  k by k
  *>           lower triangular part of the array  A must contain the lower
  *>           triangular matrix  and the strictly upper triangular part of
  *>           A is not referenced.
  *>           Note that when  DIAG = 'U' or 'u',  the diagonal elements of
  *>           A  are not referenced either,  but are assumed to be  unity.
  *> \endverbatim
  *>
  *> \param[in] LDA
  *> \verbatim
  *>          LDA is INTEGER
  *>           On entry, LDA specifies the first dimension of A as declared
  *>           in the calling (sub) program.  When  SIDE = 'L' or 'l'  then
  *>           LDA  must be at least  max( 1, m ),  when  SIDE = 'R' or 'r'
  *>           then LDA must be at least max( 1, n ).
  *> \endverbatim
  *>
  *> \param[in,out] B
  *> \verbatim
  *>          B is COMPLEX array, dimension ( LDB, N )
  *>           Before entry,  the leading  m by n part of the array  B must
  *>           contain  the  right-hand  side  matrix  B,  and  on exit  is
  *>           overwritten by the solution matrix  X.
  *> \endverbatim
  *>
  *> \param[in] LDB
  *> \verbatim
  *>          LDB is INTEGER
  *>           On entry, LDB specifies the first dimension of B as declared
  *>           in  the  calling  (sub)  program.   LDB  must  be  at  least
  *>           max( 1, m ).
  *> \endverbatim
  *
  *  Authors:
  *  ========
  *
  *> \author Univ. of Tennessee
  *> \author Univ. of California Berkeley
  *> \author Univ. of Colorado Denver
  *> \author NAG Ltd.
  *
  *> \date December 2016
  *
  *> \ingroup complex_blas_level3
  *
  *> \par Further Details:
  *  =====================
  *>
  *> \verbatim
  *>
  *>  Level 3 Blas routine.
  *>
  *>  -- Written on 8-February-1989.
  *>     Jack Dongarra, Argonne National Laboratory.
  *>     Iain Duff, AERE Harwell.
  *>     Jeremy Du Croz, Numerical Algorithms Group Ltd.
  *>     Sven Hammarling, Numerical Algorithms Group Ltd.
  *> \endverbatim
  *>
  *  =====================================================================
        SUBROUTINE CTRSM(SIDE,UPLO,TRANSA,DIAG,M,N,ALPHA,A,LDA,B,LDB)
  *
  *  -- Reference BLAS level3 routine (version 3.7.0) --
  *  -- Reference BLAS is a software package provided by Univ. of Tennessee,    --
  *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
  *     December 2016
  *
  *     .. Scalar Arguments ..
        COMPLEX ALPHA
        INTEGER LDA,LDB,M,N
        CHARACTER DIAG,SIDE,TRANSA,UPLO
  *     ..
  *     .. Array Arguments ..
        COMPLEX A(LDA,*),B(LDB,*)
  *     ..
  *
  *  =====================================================================
  *
  *     .. External Functions ..
        LOGICAL LSAME
        EXTERNAL LSAME
  *     ..
  *     .. External Subroutines ..
        EXTERNAL XERBLA
  *     ..
  *     .. Intrinsic Functions ..
        INTRINSIC CONJG,MAX
  *     ..
  *     .. Local Scalars ..
        COMPLEX TEMP
        INTEGER I,INFO,J,K,NROWA
        LOGICAL LSIDE,NOCONJ,NOUNIT,UPPER
  *     ..
  *     .. Parameters ..
        COMPLEX ONE
        PARAMETER (ONE= (1.0E+0,0.0E+0))
        COMPLEX ZERO
        PARAMETER (ZERO= (0.0E+0,0.0E+0))
  *     ..
  *
  *     Test the input parameters.
  *
        LSIDE = LSAME(SIDE,'L')
        IF (LSIDE) THEN
            NROWA = M
        ELSE
            NROWA = N
        END IF
        NOCONJ = LSAME(TRANSA,'T')
        NOUNIT = LSAME(DIAG,'N')
        UPPER = LSAME(UPLO,'U')
  *
        INFO = 0
        IF ((.NOT.LSIDE) .AND. (.NOT.LSAME(SIDE,'R'))) THEN
            INFO = 1
        ELSE IF ((.NOT.UPPER) .AND. (.NOT.LSAME(UPLO,'L'))) THEN
            INFO = 2
        ELSE IF ((.NOT.LSAME(TRANSA,'N')) .AND.
       +         (.NOT.LSAME(TRANSA,'T')) .AND.
       +         (.NOT.LSAME(TRANSA,'C'))) THEN
            INFO = 3
        ELSE IF ((.NOT.LSAME(DIAG,'U')) .AND. (.NOT.LSAME(DIAG,'N'))) THEN
            INFO = 4
        ELSE IF (M.LT.0) THEN
            INFO = 5
        ELSE IF (N.LT.0) THEN
            INFO = 6
        ELSE IF (LDA.LT.MAX(1,NROWA)) THEN
            INFO = 9
        ELSE IF (LDB.LT.MAX(1,M)) THEN
            INFO = 11
        END IF
        IF (INFO.NE.0) THEN
            CALL XERBLA('CTRSM ',INFO)
            RETURN
        END IF
  *
  *     Quick return if possible.
  *
        IF (M.EQ.0 .OR. N.EQ.0) RETURN
  *
  *     And when  alpha.eq.zero.
  *
        IF (ALPHA.EQ.ZERO) THEN
            DO 20 J = 1,N
                DO 10 I = 1,M
                    B(I,J) = ZERO
     10         CONTINUE
     20     CONTINUE
            RETURN
        END IF
  *
  *     Start the operations.
  *
        IF (LSIDE) THEN
            IF (LSAME(TRANSA,'N')) THEN
  *
  *           Form  B := alpha*inv( A )*B.
  *
                IF (UPPER) THEN
                    DO 60 J = 1,N
                        IF (ALPHA.NE.ONE) THEN
                            DO 30 I = 1,M
                                B(I,J) = ALPHA*B(I,J)
     30                     CONTINUE
                        END IF
                        DO 50 K = M,1,-1
                            IF (B(K,J).NE.ZERO) THEN
                                IF (NOUNIT) B(K,J) = B(K,J)/A(K,K)
                                DO 40 I = 1,K - 1
                                    B(I,J) = B(I,J) - B(K,J)*A(I,K)
     40                         CONTINUE
                            END IF
     50                 CONTINUE
     60             CONTINUE
                ELSE
                    DO 100 J = 1,N
                        IF (ALPHA.NE.ONE) THEN
                            DO 70 I = 1,M
                                B(I,J) = ALPHA*B(I,J)
     70                     CONTINUE
                        END IF
                        DO 90 K = 1,M
                            IF (B(K,J).NE.ZERO) THEN
                                IF (NOUNIT) B(K,J) = B(K,J)/A(K,K)
                                DO 80 I = K + 1,M
                                    B(I,J) = B(I,J) - B(K,J)*A(I,K)
     80                         CONTINUE
                            END IF
     90                 CONTINUE
    100             CONTINUE
                END IF
            ELSE
  *
  *           Form  B := alpha*inv( A**T )*B
  *           or    B := alpha*inv( A**H )*B.
  *
                IF (UPPER) THEN
                    DO 140 J = 1,N
                        DO 130 I = 1,M
                            TEMP = ALPHA*B(I,J)
                            IF (NOCONJ) THEN
                                DO 110 K = 1,I - 1
                                    TEMP = TEMP - A(K,I)*B(K,J)
    110                         CONTINUE
                                IF (NOUNIT) TEMP = TEMP/A(I,I)
                            ELSE
                                DO 120 K = 1,I - 1
                                    TEMP = TEMP - CONJG(A(K,I))*B(K,J)
    120                         CONTINUE
                                IF (NOUNIT) TEMP = TEMP/CONJG(A(I,I))
                            END IF
                            B(I,J) = TEMP
    130                 CONTINUE
    140             CONTINUE
                ELSE
                    DO 180 J = 1,N
                        DO 170 I = M,1,-1
                            TEMP = ALPHA*B(I,J)
                            IF (NOCONJ) THEN
                                DO 150 K = I + 1,M
                                    TEMP = TEMP - A(K,I)*B(K,J)
    150                         CONTINUE
                                IF (NOUNIT) TEMP = TEMP/A(I,I)
                            ELSE
                                DO 160 K = I + 1,M
                                    TEMP = TEMP - CONJG(A(K,I))*B(K,J)
    160                         CONTINUE
                                IF (NOUNIT) TEMP = TEMP/CONJG(A(I,I))
                            END IF
                            B(I,J) = TEMP
    170                 CONTINUE
    180             CONTINUE
                END IF
            END IF
        ELSE
            IF (LSAME(TRANSA,'N')) THEN
  *
  *           Form  B := alpha*B*inv( A ).
  *
                IF (UPPER) THEN
                    DO 230 J = 1,N
                        IF (ALPHA.NE.ONE) THEN
                            DO 190 I = 1,M
                                B(I,J) = ALPHA*B(I,J)
    190                     CONTINUE
                        END IF
                        DO 210 K = 1,J - 1
                            IF (A(K,J).NE.ZERO) THEN
                                DO 200 I = 1,M
                                    B(I,J) = B(I,J) - A(K,J)*B(I,K)
    200                         CONTINUE
                            END IF
    210                 CONTINUE
                        IF (NOUNIT) THEN
                            TEMP = ONE/A(J,J)
                            DO 220 I = 1,M
                                B(I,J) = TEMP*B(I,J)
    220                     CONTINUE
                        END IF
    230             CONTINUE
                ELSE
                    DO 280 J = N,1,-1
                        IF (ALPHA.NE.ONE) THEN
                            DO 240 I = 1,M
                                B(I,J) = ALPHA*B(I,J)
    240                     CONTINUE
                        END IF
                        DO 260 K = J + 1,N
                            IF (A(K,J).NE.ZERO) THEN
                                DO 250 I = 1,M
                                    B(I,J) = B(I,J) - A(K,J)*B(I,K)
    250                         CONTINUE
                            END IF
    260                 CONTINUE
                        IF (NOUNIT) THEN
                            TEMP = ONE/A(J,J)
                            DO 270 I = 1,M
                                B(I,J) = TEMP*B(I,J)
    270                     CONTINUE
                        END IF
    280             CONTINUE
                END IF
            ELSE
  *
  *           Form  B := alpha*B*inv( A**T )
  *           or    B := alpha*B*inv( A**H ).
  *
                IF (UPPER) THEN
                    DO 330 K = N,1,-1
                        IF (NOUNIT) THEN
                            IF (NOCONJ) THEN
                                TEMP = ONE/A(K,K)
                            ELSE
                                TEMP = ONE/CONJG(A(K,K))
                            END IF
                            DO 290 I = 1,M
                                B(I,K) = TEMP*B(I,K)
    290                     CONTINUE
                        END IF
                        DO 310 J = 1,K - 1
                            IF (A(J,K).NE.ZERO) THEN
                                IF (NOCONJ) THEN
                                    TEMP = A(J,K)
                                ELSE
                                    TEMP = CONJG(A(J,K))
                                END IF
                                DO 300 I = 1,M
                                    B(I,J) = B(I,J) - TEMP*B(I,K)
    300                         CONTINUE
                            END IF
    310                 CONTINUE
                        IF (ALPHA.NE.ONE) THEN
                            DO 320 I = 1,M
                                B(I,K) = ALPHA*B(I,K)
    320                     CONTINUE
                        END IF
    330             CONTINUE
                ELSE
                    DO 380 K = 1,N
                        IF (NOUNIT) THEN
                            IF (NOCONJ) THEN
                                TEMP = ONE/A(K,K)
                            ELSE
                                TEMP = ONE/CONJG(A(K,K))
                            END IF
                            DO 340 I = 1,M
                                B(I,K) = TEMP*B(I,K)
    340                     CONTINUE
                        END IF
                        DO 360 J = K + 1,N
                            IF (A(J,K).NE.ZERO) THEN
                                IF (NOCONJ) THEN
                                    TEMP = A(J,K)
                                ELSE
                                    TEMP = CONJG(A(J,K))
                                END IF
                                DO 350 I = 1,M
                                    B(I,J) = B(I,J) - TEMP*B(I,K)
    350                         CONTINUE
                            END IF
    360                 CONTINUE
                        IF (ALPHA.NE.ONE) THEN
                            DO 370 I = 1,M
                                B(I,K) = ALPHA*B(I,K)
    370                     CONTINUE
                        END IF
    380             CONTINUE
                END IF
            END IF
        END IF
  *
        RETURN
  *
  *     End of CTRSM .
  *
        END
  