dlauum()

subroutine dlauum	(	character	uplo,
		integer	n,
		double precision, dimension( lda, * )	a,
		integer	lda,
		integer	info )

DLAUUM computes the product UUH or LHL, where U and L are upper or lower triangular matrices (blocked algorithm).

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Purpose:

!>
!> DLAUUM computes the product U * U**T or L**T * 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.
!> 

Parameters

[in]	UPLO	!> UPLO is CHARACTER*1 !> Specifies whether the triangular factor stored in the array A !> is upper or lower triangular: !> = 'U': Upper triangular !> = 'L': Lower triangular !>
[in]	N	!> N is INTEGER !> The order of the triangular factor U or L. N >= 0. !>
[in,out]	A	!> A is DOUBLE PRECISION 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**T; !> if UPLO = 'L', the lower triangle of A is overwritten with !> the lower triangle of the product L**T * L. !>
[in]	LDA	!> LDA is INTEGER !> The leading dimension of the array A. LDA >= max(1,N). !>
[out]	INFO	!> INFO is INTEGER !> = 0: successful exit !> < 0: if INFO = -k, the k-th argument had an illegal value !>

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.