trusty (3) ctrmm.3.gz

Provided by: libblas-doc_1.2.20110419-7_all bug

NAME

       CTRMM  -  perform  one  of  the  matrix-matrix operations   B := alpha*op( A )*B, or B := alpha*B*op( A )
       where alpha is a scalar, B is an m by n matrix, 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' or op( A ) = conjg( A' )

SYNOPSIS

       SUBROUTINE CTRMM ( SIDE, UPLO, TRANSA, DIAG, M, N, ALPHA, A, LDA, B, LDB )

           CHARACTER*1  SIDE, UPLO, TRANSA, DIAG

           INTEGER      M, N, LDA, LDB

           COMPLEX      ALPHA

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

PURPOSE

       CTRMM  performs one of the matrix-matrix operations

PARAMETERS

       SIDE   - CHARACTER*1.
              On entry,  SIDE specifies whether  op( A ) multiplies B from the left or right as follows:

              SIDE = 'L' or 'l'   B := alpha*op( A )*B.

              SIDE = 'R' or 'r'   B := alpha*B*op( A ).

              Unchanged on exit.

       UPLO   - 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.

              Unchanged on exit.

              TRANSA  -  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'.

              TRANSA = 'C' or 'c'   op( A ) = conjg( A' ).

              Unchanged on exit.

       DIAG   - 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.

              Unchanged on exit.

       M      - INTEGER.
              On entry, M specifies the number of rows of B. M must be at least zero.  Unchanged on exit.

       N      - INTEGER.
              On entry, N specifies the number of columns of B.  N must be at least zero.  Unchanged on exit.

       ALPHA  - 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.  Unchanged on exit.

       A      - COMPLEX          array of DIMENSION ( LDA, k ), where k is m
              when   SIDE  =  'L' or 'l'  and 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.  Unchanged on exit.

       LDA    - 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 ).  Unchanged on exit.

       B      - COMPLEX          array of DIMENSION ( LDB, n ).
              Before  entry,  the leading  m by n part of the array  B must contain the matrix  B,  and  on exit
              is overwritten  by the transformed matrix.

       LDB    - 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 ).  Unchanged on exit.

              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.