NAME

clauum - compute the product U ∗ U’ or L’ ∗ L, where the triangular factor U or L is stored in the upper or lower triangular part of the array A

SYNOPSIS

SUBROUTINE CLAUUM( UPLO, N, A, LDA, INFO )

CHARACTER UPLO

INTEGER INFO, LDA, N

COMPLEX A( LDA, ∗ )

#include <sunperf.h>

void clauum(char uplo, int n, complex ∗ca, int lda, int ∗info) ;

PURPOSE

CLAUUM computes the product U ∗ U’ or L’ ∗ L, where the triangular factor U or L is stored in the upper or lower triangular part of the array A. 
 
If UPLO = ’U’ or ’u’ then the upper triangle of the result is stored, overwriting the factor U in A.
If UPLO = ’L’ or ’l’ then the lower triangle of the result is stored, overwriting the factor L in A.
 
This is the blocked form of the algorithm, calling Level 3 BLAS.
 

ARGUMENTS

UPLO (input) CHARACTER∗1
Specifies whether the triangular factor stored in the array A is upper or lower triangular:
= ’U’:  Upper triangular
= ’L’:  Lower triangular

N (input) INTEGER
The order of the triangular factor U or L.  N >= 0.

A (input/output) COMPLEX array, dimension (LDA,N)
On entry, the triangular factor U or L. On exit, if UPLO = ’U’, the upper triangle of A is overwritten with the upper triangle of the product U ∗ U’; if UPLO = ’L’, the lower triangle of A is overwritten with the lower triangle of the product L’ ∗ L.

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

INFO (output) INTEGER
= 0: successful exit
< 0: if INFO = -k, the k-th argument had an illegal value

SunOS 5.0  —  Last change: 10 Dec 1998