LAPACK  3.5.0
LAPACK: Linear Algebra PACKage
 All Files Functions Typedefs Macros
zlagsy.f File Reference

Go to the source code of this file.

Functions/Subroutines

subroutine zlagsy (N, K, D, A, LDA, ISEED, WORK, INFO)
 ZLAGSY More...
 

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
 additional unitary transformations.
Parameters
[in]N
          N is INTEGER
          The order of the matrix A.  N >= 0.
[in]K
          K is INTEGER
          The number of nonzero subdiagonals within the band of A.
          0 <= K <= N-1.
[in]D
          D is DOUBLE PRECISION array, dimension (N)
          The diagonal elements of the diagonal matrix D.
[out]A
          A is COMPLEX*16 array, dimension (LDA,N)
          The generated n by n symmetric matrix A (the full matrix is
          stored).
[in]LDA
          LDA is INTEGER
          The leading dimension of the array A.  LDA >= N.
[in,out]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.
[out]WORK
          WORK is COMPLEX*16 array, dimension (2*N)
[out]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
Univ. of Colorado Denver
NAG Ltd.
Date
November 2011

Definition at line 103 of file zlagsy.f.

Here is the call graph for this function:

Here is the caller graph for this function: