# 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

Univ. of Colorado Denver

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