# zlagsy.f - Man Page

TESTING/MATGEN/zlagsy.f

## Synopsis

### Functions/Subroutines

subroutine zlagsy (n, k, d, a, lda, iseed, work, info)
ZLAGSY

## Function/Subroutine Documentation

### subroutine zlagsy (integer n, integer k, double precision, dimension( * ) d, complex*16, dimension( lda, * ) a, integer lda, integer, dimension( 4 ) iseed, complex*16, dimension( * ) work, integer info)

ZLAGSY

Purpose:

``` ZLAGSY generates a complex symmetric matrix A, by pre- and post-
multiplying a real diagonal matrix D with a random unitary matrix:
A = U*D*U**T. The semi-bandwidth may then be reduced to k by
Parameters

N

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

K

```          K is INTEGER
The number of nonzero subdiagonals within the band of A.
0 <= K <= N-1.```

D

```          D is DOUBLE PRECISION array, dimension (N)
The diagonal elements of the diagonal matrix D.```

A

```          A is COMPLEX*16 array, dimension (LDA,N)
The generated n by n symmetric matrix A (the full matrix is
stored).```

LDA

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

ISEED

```          ISEED is INTEGER array, dimension (4)
On entry, the seed of the random number generator; the array
elements must be between 0 and 4095, and ISEED(4) must be
odd.
On exit, the seed is updated.```

WORK

`          WORK is COMPLEX*16 array, dimension (2*N)`

INFO

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

Univ. of Tennessee

Univ. of California Berkeley

NAG Ltd.

Definition at line 101 of file zlagsy.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

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

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