# dlaset.f man page

dlaset.f —

## Synopsis

### Functions/Subroutines

subroutinedlaset(UPLO, M, N, ALPHA, BETA, A, LDA)DLASETinitializes the off-diagonal elements and the diagonal elements of a matrix to given values.

## Function/Subroutine Documentation

### subroutine dlaset (characterUPLO, integerM, integerN, double precisionALPHA, double precisionBETA, double precision, dimension( lda, * )A, integerLDA)

**DLASET** initializes the off-diagonal elements and the diagonal elements of a matrix to given values.

**Purpose:**

```
DLASET initializes an m-by-n matrix A to BETA on the diagonal and
ALPHA on the offdiagonals.
```

**Parameters:**

*UPLO*

```
UPLO is 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*

```
M is INTEGER
The number of rows of the matrix A. M >= 0.
```

*N*

```
N is INTEGER
The number of columns of the matrix A. N >= 0.
```

*ALPHA*

```
ALPHA is DOUBLE PRECISION
The constant to which the offdiagonal elements are to be set.
```

*BETA*

```
BETA is DOUBLE PRECISION
The constant to which the diagonal elements are to be set.
```

*A*

```
A is 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*

```
LDA is INTEGER
The leading dimension of the array A. LDA >= max(1,M).
```

**Author:**

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

**Date:**

September 2012

Definition at line 111 of file dlaset.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

dlaset(3) is an alias of dlaset.f(3).