CLAUUM(1) LAPACK auxiliary routine (version 3.2) CLAUUM(1)NAME
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
SYNOPSIS
SUBROUTINE CLAUUM( UPLO, N, A, LDA, INFO )
CHARACTER UPLO
INTEGER INFO, LDA, N
COMPLEX A( LDA, * )
PURPOSE
CLAUUM computes the product U * U' or L' * L, where the triangular fac‐
tor 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 tri‐
angle 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
LAPACK auxiliary routine (versioNovember 2008 CLAUUM(1)