lauum - Man Page

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

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

A

          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.

Definition at line 101 of file clauum.f.

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.

 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

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

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.

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.

Definition at line 101 of file dlauum.f.

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.

 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

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

A

          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.

Definition at line 101 of file slauum.f.

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.

 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

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

A

          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.

Definition at line 101 of file zlauum.f.

Author

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Tue Nov 28 2023 12:08:43 Version 3.12.0 LAPACK