# dlattr.f - Man Page

TESTING/LIN/dlattr.f

## Synopsis

### Functions/Subroutines

subroutine dlattr (imat, uplo, trans, diag, iseed, n, a, lda, b, work, info)
DLATTR

## Function/Subroutine Documentation

### subroutine dlattr (integer imat, character uplo, character trans, character diag, integer, dimension( 4 ) iseed, integer n, double precision, dimension( lda, * ) a, integer lda, double precision, dimension( * ) b, double precision, dimension( * ) work, integer info)

DLATTR

Purpose:

``` DLATTR generates a triangular test matrix.
IMAT and UPLO uniquely specify the properties of the test
matrix, which is returned in the array A.```
Parameters

IMAT

```          IMAT is INTEGER
An integer key describing which matrix to generate for this
path.```

UPLO

```          UPLO is CHARACTER*1
Specifies whether the matrix A will be upper or lower
triangular.
= 'U':  Upper triangular
= 'L':  Lower triangular```

TRANS

```          TRANS is CHARACTER*1
Specifies whether the matrix or its transpose will be used.
= 'N':  No transpose
= 'T':  Transpose
= 'C':  Conjugate transpose (= Transpose)```

DIAG

```          DIAG is CHARACTER*1
Specifies whether or not the matrix A is unit triangular.
= 'N':  Non-unit triangular
= 'U':  Unit triangular```

ISEED

```          ISEED is INTEGER array, dimension (4)
The seed vector for the random number generator (used in
DLATMS).  Modified on exit.```

N

```          N is INTEGER
The order of the matrix to be generated.```

A

```          A is DOUBLE PRECISION array, dimension (LDA,N)
The triangular matrix A.  If UPLO = 'U', the leading n by n
upper triangular part of the array A contains the upper
triangular matrix, and the strictly lower triangular part of
A is not referenced.  If UPLO = 'L', the leading n by n lower
triangular part of the array A contains the lower triangular
matrix, and the strictly upper triangular part of A is not
referenced.  If DIAG = 'U', the diagonal elements of A are
set so that A(k,k) = k for 1 <= k <= n.```

LDA

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

B

```          B is DOUBLE PRECISION array, dimension (N)
The right hand side vector, if IMAT > 10.```

WORK

`          WORK is DOUBLE PRECISION array, dimension (3*N)`

INFO

```          INFO is INTEGER
= 0:  successful exit
< 0: if INFO = -k, the k-th argument had an illegal value```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 131 of file dlattr.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

The man page dlattr(3) is an alias of dlattr.f(3).

Tue Nov 28 2023 12:08:43 Version 3.12.0 LAPACK