Ubuntu Manpage: lauum - lauum: triangular multiply: U^H U

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NAME

       lauum - lauum: triangular multiply: U^H U

SYNOPSIS

   Functions
       subroutine clauum (uplo, n, a, lda, info)
           CLAUUM computes the product UUH or LHL, where U and L are upper or lower triangular matrices (blocked
           algorithm).
       subroutine dlauum (uplo, n, a, lda, info)
           DLAUUM computes the product UUH or LHL, where U and L are upper or lower triangular matrices (blocked
           algorithm).
       subroutine slauum (uplo, n, a, lda, info)
           SLAUUM computes the product UUH or LHL, where U and L are upper or lower triangular matrices (blocked
           algorithm).
       subroutine zlauum (uplo, n, a, lda, info)
           ZLAUUM computes the product UUH or LHL, where U and L are upper or lower triangular matrices (blocked
           algorithm).

Detailed Description

Function Documentation

subroutine clauum (character uplo, integer n, complex, dimension( lda, * ) a, integer lda, integer info)
CLAUUM computes the product UUH or LHL, where U and L are upper or lower triangular matrices (blocked
algorithm).

Purpose:

CLAUUM computes the product U * U**H or L**H * 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
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

N is INTEGER
The order of the triangular factor U or L. N >= 0.

A is 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**H;
if UPLO = 'L', the lower triangle of A is overwritten with
the lower triangle of the product L**H * L.

LDA

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

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.

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).

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.

This is the blocked form of the algorithm, calling Level 3 BLAS.

Parameters
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

N is INTEGER
The order of the triangular factor U or L. N >= 0.

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.

LDA

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

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.

subroutine slauum (character uplo, integer n, real, dimension( lda, * ) a, integer lda, integer info)
SLAUUM computes the product UUH or LHL, where U and L are upper or lower triangular matrices (blocked
algorithm).

Purpose:

SLAUUM 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.

This is the blocked form of the algorithm, calling Level 3 BLAS.

Parameters
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

N is INTEGER
The order of the triangular factor U or L. N >= 0.

A is REAL 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.

LDA

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

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.

subroutine zlauum (character uplo, integer n, complex*16, dimension( lda, * ) a, integer lda, integer info)
ZLAUUM computes the product UUH or LHL, where U and L are upper or lower triangular matrices (blocked
algorithm).

Purpose:

ZLAUUM computes the product U * U**H or L**H * L, where the triangular
factor U or L is stored in the upper or lower triangular part of
the array A.

This is the blocked form of the algorithm, calling Level 3 BLAS.

Parameters
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

N is INTEGER
The order of the triangular factor U or L. N >= 0.

A is COMPLEX*16 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**H;
if UPLO = 'L', the lower triangle of A is overwritten with
the lower triangle of the product L**H * L.

LDA

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

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.

Author

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Version 3.12.0                               Thu Aug 8 2024 12:55:44                                    lauum(3)