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SLAUUM(1) LAPACK auxiliary routine (version 3.2) SLAUUM(1)

NAME

SLAUUM - 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

UPLO, N, A, LDA, INFO )

CHARACTER UPLO INTEGER INFO, LDA, N REAL A( LDA, * )

PURPOSE

SLAUUM 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

Specifies whether the triangular factor stored in the array A is upper or lower triangular:
= 'U': Upper triangular
= 'L': Lower triangular
The order of the triangular factor U or L. N >= 0.
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.
The leading dimension of the array A. LDA >= max(1,N).
= 0: successful exit
< 0: if INFO = -k, the k-th argument had an illegal value
November 2008 LAPACK auxiliary routine (version 3.2)