DTRMVT(l) ) DTRMVT(l)NAME
DTRMVT - perform the matrix-vector operations x := T' *y, and w := T
*z,
SYNOPSIS
SUBROUTINE DTRMVT( UPLO, N, T, LDT, X, INCX, Y, INCY, W, INCW, Z, INCZ
)
CHARACTER UPLO
INTEGER INCW, INCX, INCY, INCZ, LDT, N
DOUBLE PRECISION T( LDT, * ), W( * ), X( * ), Y( * ), Z( *
)
PURPOSE
DTRMVT performs the matrix-vector operations x := T' *y, and w := T *z,
where x is an n element vector and T is an n by n
upper or lower triangular matrix.
ARGUMENTS
UPLO - CHARACTER*1.
On entry, UPLO specifies whether the matrix 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.
N - INTEGER.
On entry, N specifies the order of the matrix A. N must be at
least zero. Unchanged on exit.
T - DOUBLE PRECISION array of DIMENSION ( LDT, n ).
Before entry with UPLO = 'U' or 'u', the leading n by n upper
triangular part of the array T must contain the upper triangular
matrix and the strictly lower triangular part of T is not refer‐
enced. Before entry with UPLO = 'L' or 'l', the leading n by n
lower triangular part of the array T must contain the lower tri‐
angular matrix and the strictly upper triangular part of T is
not referenced.
LDT - INTEGER.
On entry, LDA specifies the first dimension of A as declared in
the calling (sub) program. LDA must be at least max( 1, n ).
Unchanged on exit.
X - DOUBLE PRECISION array of dimension at least
( 1 + ( n - 1 )*abs( INCX ) ). On exit, X = T' * y
INCX - INTEGER.
On entry, INCX specifies the increment for the elements of X.
INCX must not be zero. Unchanged on exit.
Y - DOUBLE PRECISION array of dimension at least
( 1 + ( n - 1 )*abs( INCY ) ). Before entry, the incremented
array Y must contain the n element vector y. Unchanged on exit.
INCY - INTEGER.
On entry, INCY specifies the increment for the elements of Y.
INCY must not be zero. Unchanged on exit.
W - DOUBLE PRECISION array of dimension at least
( 1 + ( n - 1 )*abs( INCW ) ). On exit, W = T * z
INCW - INTEGER.
On entry, INCW specifies the increment for the elements of W.
INCW must not be zero. Unchanged on exit.
Z - DOUBLE PRECISION array of dimension at least
( 1 + ( n - 1 )*abs( INCZ ) ). Before entry, the incremented
array Z must contain the n element vector z. Unchanged on exit.
INCY - INTEGER.
On entrz, INCY specifies the increment for the elements of Y.
INCY must not be zero. Unchanged on exit.
Level 2 Blas routine.
Test the input parameters.
Quick return if possible.
End of DTRMVT.
ScaLAPACK version 1.7 13 August 2001 DTRMVT(l)
