# zlauum.f - Man Page

SRC/zlauum.f

## Synopsis

### Functions/Subroutines

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).

## Function/Subroutine Documentation

### 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

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

The man page zlauum(3) is an alias of zlauum.f(3).

Tue Nov 28 2023 12:08:42 Version 3.12.0 LAPACK