# dqrt15.f - Man Page

TESTING/LIN/dqrt15.f

## Synopsis

### Functions/Subroutines

subroutine dqrt15 (scale, rksel, m, n, nrhs, a, lda, b, ldb, s, rank, norma, normb, iseed, work, lwork)
DQRT15

## Function/Subroutine Documentation

### subroutine dqrt15 (integer scale, integer rksel, integer m, integer n, integer nrhs, double precision, dimension( lda, * ) a, integer lda, double precision, dimension( ldb, * ) b, integer ldb, double precision, dimension( * ) s, integer rank, double precision norma, double precision normb, integer, dimension( 4 ) iseed, double precision, dimension( lwork ) work, integer lwork)

DQRT15

Purpose:

``` DQRT15 generates a matrix with full or deficient rank and of various
norms.```
Parameters

SCALE

```          SCALE is INTEGER
SCALE = 1: normally scaled matrix
SCALE = 2: matrix scaled up
SCALE = 3: matrix scaled down```

RKSEL

```          RKSEL is INTEGER
RKSEL = 1: full rank matrix
RKSEL = 2: rank-deficient matrix```

M

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

N

```          N is INTEGER
The number of columns of A.```

NRHS

```          NRHS is INTEGER
The number of columns of B.```

A

```          A is DOUBLE PRECISION array, dimension (LDA,N)
The M-by-N matrix A.```

LDA

```          LDA is INTEGER
The leading dimension of the array A.```

B

```          B is DOUBLE PRECISION array, dimension (LDB, NRHS)
A matrix that is in the range space of matrix A.```

LDB

```          LDB is INTEGER
The leading dimension of the array B.```

S

```          S is DOUBLE PRECISION array, dimension MIN(M,N)
Singular values of A.```

RANK

```          RANK is INTEGER
number of nonzero singular values of A.```

NORMA

```          NORMA is DOUBLE PRECISION
one-norm of A.```

NORMB

```          NORMB is DOUBLE PRECISION
one-norm of B.```

ISEED

```          ISEED is integer array, dimension (4)
seed for random number generator.```

WORK

`          WORK is DOUBLE PRECISION array, dimension (LWORK)`

LWORK

```          LWORK is INTEGER
length of work space required.
LWORK >= MAX(M+MIN(M,N),NRHS*MIN(M,N),2*N+M)```
Author

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 146 of file dqrt15.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

The man page dqrt15(3) is an alias of dqrt15.f(3).

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