DLASET(3F)DLASET(3F)NAME
DLASET - initialize an m-by-n matrix A to BETA on the diagonal and ALPHA
on the offdiagonals
SYNOPSIS
SUBROUTINE DLASET( UPLO, M, N, ALPHA, BETA, A, LDA )
CHARACTER UPLO
INTEGER LDA, M, N
DOUBLE PRECISION ALPHA, BETA
DOUBLE PRECISION A( LDA, * )
PURPOSE
DLASET initializes an m-by-n matrix A to BETA on the diagonal and ALPHA
on the offdiagonals.
ARGUMENTS
UPLO (input) CHARACTER*1
Specifies the part of the matrix A to be set. = 'U': Upper
triangular part is set; the strictly lower triangular part of A
is not changed. = 'L': Lower triangular part is set; the
strictly upper triangular part of A is not changed. Otherwise:
All of the matrix A is set.
M (input) INTEGER
The number of rows of the matrix A. M >= 0.
N (input) INTEGER
The number of columns of the matrix A. N >= 0.
ALPHA (input) DOUBLE PRECISION
The constant to which the offdiagonal elements are to be set.
BETA (input) DOUBLE PRECISION
The constant to which the diagonal elements are to be set.
A (input/output) DOUBLE PRECISION array, dimension (LDA,N)
On exit, the leading m-by-n submatrix of A is set as follows:
if UPLO = 'U', A(i,j) = ALPHA, 1<=i<=j-1, 1<=j<=n, if UPLO = 'L',
A(i,j) = ALPHA, j+1<=i<=m, 1<=j<=n, otherwise, A(i,j) =
ALPHA, 1<=i<=m, 1<=j<=n, i.ne.j,
and, for all UPLO, A(i,i) = BETA, 1<=i<=min(m,n).
LDA (input) INTEGER
The leading dimension of the array A. LDA >= max(1,M).
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