?laset

Initializes the off-diagonal elements and the diagonal elements of a matrix to given values.

Syntax

call slaset( uplo, m, n, alpha, beta, a, lda )

call dlaset( uplo, m, n, alpha, beta, a, lda )

call claset( uplo, m, n, alpha, beta, a, lda )

call zlaset( uplo, m, n, alpha, beta, a, lda )

Include Files

The FORTRAN 77 interfaces are specified in the mkl_lapack.fi include file (to be used in Fortran programs) and in the mkl_lapack.h include file (to be used in C programs).

Description

The routine initializes an m-by-n matrix A to beta on the diagonal and alpha on the off-diagonals.

Input Parameters

uplo

CHARACTER*1. Specifies the part of the matrix A to be set.

If uplo = 'U', upper triangular part is set; the strictly lower triangular part of A is not changed.

If uplo = '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

INTEGER. The number of rows of the matrix A. m ≥ 0.

n

INTEGER. The number of columns of the matrix A.

n ≥ 0.

alpha, beta

REAL for slaset

DOUBLE PRECISION for dlaset

COMPLEX for claset

DOUBLE COMPLEX for zlaset.

The constants to which the off-diagonal and diagonal elements are to be set, respectively.

a

REAL for slaset

DOUBLE PRECISION for dlaset

COMPLEX for claset

DOUBLE COMPLEX for zlaset.

Array, DIMENSION (lda, n).

On entry, the m-by-n matrix A.

lda

INTEGER. The leading dimension of the array a.

lda ≥ max(1,m).

Output Parameters

a

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 ≠ j,

and, for all uplo, A(i,i) = beta, 1≤i≤min(m, n).