1CTRMM(1) BLAS routine CTRMM(1)
2
6 CTRMM - one of the matrix-matrix operations B := alpha*op( A )*B, or
7 B := alpha*B*op( A ) where alpha is a scalar, B is an m by n matrix, A
8 is a unit, or non-unit, upper or lower triangular matrix and op( A ) is
9 one of op( A ) = A or op( A ) = A' or op( A ) = conjg( A' )
10
12 SUBROUTINE CTRMM(SIDE,UPLO,TRANSA,DIAG,M,N,ALPHA,A,LDA,B,LDB)
13 COMPLEX ALPHA
15 INTEGER LDA,LDB,M,N
17 CHARACTER DIAG,SIDE,TRANSA,UPLO
19 COMPLEX A(LDA,*),B(LDB,*)
21
23 CTRMM performs one of the matrix-matrix operations
24
27 SIDE - CHARACTER*1.
28 On entry, SIDE specifies whether op( A ) multiplies B from the
29 left or right as follows:
30 SIDE = 'L' or 'l' B := alpha*op( A )*B.
32 SIDE = 'R' or 'r' B := alpha*B*op( A ).
34 Unchanged on exit.
36 UPLO - CHARACTER*1.
38 On entry, UPLO specifies whether the matrix A is an upper or
39 lower triangular matrix as follows:
40 UPLO = 'U' or 'u' A is an upper triangular matrix.
42 UPLO = 'L' or 'l' A is a lower triangular matrix.
44 Unchanged on exit.
46 TRANSA - CHARACTER*1. On entry, TRANSA specifies the form of
48 op( A ) to be used in the matrix multiplication as follows:
49 TRANSA = 'N' or 'n' op( A ) = A.
51 TRANSA = 'T' or 't' op( A ) = A'.
53 TRANSA = 'C' or 'c' op( A ) = conjg( A' ).
55 Unchanged on exit.
57 DIAG - CHARACTER*1.
59 On entry, DIAG specifies whether or not A is unit triangular as
60 follows:
61 DIAG = 'U' or 'u' A is assumed to be unit triangular.
63 DIAG = 'N' or 'n' A is not assumed to be unit triangular.
65 Unchanged on exit.
67 M - INTEGER.
69 On entry, M specifies the number of rows of B. M must be at
70 least zero. Unchanged on exit.
71 N - INTEGER.
73 On entry, N specifies the number of columns of B. N must be at
74 least zero. Unchanged on exit.
75 ALPHA - COMPLEX .
77 On entry, ALPHA specifies the scalar alpha. When alpha is
78 zero then A is not referenced and B need not be set before
79 entry. Unchanged on exit.
80 A - COMPLEX array of DIMENSION ( LDA, k ), where k is m
82 when SIDE = 'L' or 'l' and is n when SIDE = 'R' or 'r'.
83 Before entry with UPLO = 'U' or 'u', the leading k by k
84 upper triangular part of the array A must contain the upper
85 triangular matrix and the strictly lower triangular part of A
86 is not referenced. Before entry with UPLO = 'L' or 'l', the
87 leading k by k lower triangular part of the array A must con‐
88 tain the lower triangular matrix and the strictly upper trian‐
89 gular part of A is not referenced. Note that when DIAG = 'U'
90 or 'u', the diagonal elements of A are not referenced either,
91 but are assumed to be unity. Unchanged on exit.
92 LDA - INTEGER.
94 On entry, LDA specifies the first dimension of A as declared in
95 the calling (sub) program. When SIDE = 'L' or 'l' then LDA
96 must be at least max( 1, m ), when SIDE = 'R' or 'r' then LDA
97 must be at least max( 1, n ). Unchanged on exit.
98 B - COMPLEX array of DIMENSION ( LDB, n ).
100 Before entry, the leading m by n part of the array B must
101 contain the matrix B, and on exit is overwritten by the
102 transformed matrix.
103 LDB - INTEGER.
105 On entry, LDB specifies the first dimension of B as declared in
106 the calling (sub) program. LDB must be at least max( 1,
107 m ). Unchanged on exit.
108 Level 3 Blas routine.
110 -- Written on 8-February-1989. Jack Dongarra, Argonne National
112 Laboratory. Iain Duff, AERE Harwell. Jeremy Du Croz, Numerical
113 Algorithms Group Ltd. Sven Hammarling, Numerical Algorithms
114 Group Ltd.
115BLAS routine November 2006 CTRMM(1)