1ZTRMM(1) BLAS routine ZTRMM(1)
2
6 ZTRMM - 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 ZTRMM(SIDE,UPLO,TRANSA,DIAG,M,N,ALPHA,A,LDA,B,LDB)
13 DOUBLE COMPLEX
15 ALPHA
16 INTEGER LDA,LDB,M,N
18 CHARACTER DIAG,SIDE,TRANSA,UPLO
20 DOUBLE COMPLEX
22 A(LDA,*),B(LDB,*)
23
25 ZTRMM performs one of the matrix-matrix operations
26
29 SIDE - CHARACTER*1.
30 On entry, SIDE specifies whether op( A ) multiplies B from the
31 left or right as follows:
32 SIDE = 'L' or 'l' B := alpha*op( A )*B.
34 SIDE = 'R' or 'r' B := alpha*B*op( A ).
36 Unchanged on exit.
38 UPLO - CHARACTER*1.
40 On entry, UPLO specifies whether the matrix A is an upper or
41 lower triangular matrix as follows:
42 UPLO = 'U' or 'u' A is an upper triangular matrix.
44 UPLO = 'L' or 'l' A is a lower triangular matrix.
46 Unchanged on exit.
48 TRANSA - CHARACTER*1. On entry, TRANSA specifies the form of
50 op( A ) to be used in the matrix multiplication as follows:
51 TRANSA = 'N' or 'n' op( A ) = A.
53 TRANSA = 'T' or 't' op( A ) = A'.
55 TRANSA = 'C' or 'c' op( A ) = conjg( A' ).
57 Unchanged on exit.
59 DIAG - CHARACTER*1.
61 On entry, DIAG specifies whether or not A is unit triangular as
62 follows:
63 DIAG = 'U' or 'u' A is assumed to be unit triangular.
65 DIAG = 'N' or 'n' A is not assumed to be unit triangular.
67 Unchanged on exit.
69 M - INTEGER.
71 On entry, M specifies the number of rows of B. M must be at
72 least zero. Unchanged on exit.
73 N - INTEGER.
75 On entry, N specifies the number of columns of B. N must be at
76 least zero. Unchanged on exit.
77 ALPHA - COMPLEX*16 .
79 On entry, ALPHA specifies the scalar alpha. When alpha is
80 zero then A is not referenced and B need not be set before
81 entry. Unchanged on exit.
82 A - COMPLEX*16 array of DIMENSION ( LDA, k ), where k is m
84 when SIDE = 'L' or 'l' and is n when SIDE = 'R' or 'r'.
85 Before entry with UPLO = 'U' or 'u', the leading k by k
86 upper triangular part of the array A must contain the upper
87 triangular matrix and the strictly lower triangular part of A
88 is not referenced. Before entry with UPLO = 'L' or 'l', the
89 leading k by k lower triangular part of the array A must con‐
90 tain the lower triangular matrix and the strictly upper trian‐
91 gular part of A is not referenced. Note that when DIAG = 'U'
92 or 'u', the diagonal elements of A are not referenced either,
93 but are assumed to be unity. Unchanged on exit.
94 LDA - INTEGER.
96 On entry, LDA specifies the first dimension of A as declared in
97 the calling (sub) program. When SIDE = 'L' or 'l' then LDA
98 must be at least max( 1, m ), when SIDE = 'R' or 'r' then LDA
99 must be at least max( 1, n ). Unchanged on exit.
100 B - COMPLEX*16 array of DIMENSION ( LDB, n ).
102 Before entry, the leading m by n part of the array B must
103 contain the matrix B, and on exit is overwritten by the
104 transformed matrix.
105 LDB - INTEGER.
107 On entry, LDB specifies the first dimension of B as declared in
108 the calling (sub) program. LDB must be at least max( 1,
109 m ). Unchanged on exit.
110 Level 3 Blas routine.
112 -- Written on 8-February-1989. Jack Dongarra, Argonne National
114 Laboratory. Iain Duff, AERE Harwell. Jeremy Du Croz, Numerical
115 Algorithms Group Ltd. Sven Hammarling, Numerical Algorithms
116 Group Ltd.
117BLAS routine November 2006 ZTRMM(1)