LAPACK
3.6.1
LAPACK: Linear Algebra PACKage
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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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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.
[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 |
Definition at line 104 of file dlauum.f.