# slarfx.f - Man Page

SRC/slarfx.f

## Synopsis

### Functions/Subroutines

subroutine slarfx (side, m, n, v, tau, c, ldc, work)
SLARFX applies an elementary reflector to a general rectangular matrix, with loop unrolling when the reflector has order ≤ 10.

## Function/Subroutine Documentation

### subroutine slarfx (character side, integer m, integer n, real, dimension( * ) v, real tau, real, dimension( ldc, * ) c, integer ldc, real, dimension( * ) work)

SLARFX applies an elementary reflector to a general rectangular matrix, with loop unrolling when the reflector has order ≤ 10.

Purpose:

``` SLARFX applies a real elementary reflector H to a real m by n
matrix C, from either the left or the right. H is represented in the
form

H = I - tau * v * v**T

where tau is a real scalar and v is a real vector.

If tau = 0, then H is taken to be the unit matrix

This version uses inline code if H has order < 11.```
Parameters

SIDE

```          SIDE is CHARACTER*1
= 'L': form  H * C
= 'R': form  C * H```

M

```          M is INTEGER
The number of rows of the matrix C.```

N

```          N is INTEGER
The number of columns of the matrix C.```

V

```          V is REAL array, dimension (M) if SIDE = 'L'
or (N) if SIDE = 'R'
The vector v in the representation of H.```

TAU

```          TAU is REAL
The value tau in the representation of H.```

C

```          C is REAL array, dimension (LDC,N)
On entry, the m by n matrix C.
On exit, C is overwritten by the matrix H * C if SIDE = 'L',
or C * H if SIDE = 'R'.```

LDC

```          LDC is INTEGER
The leading dimension of the array C. LDC >= (1,M).```

WORK

```          WORK is REAL array, dimension
(N) if SIDE = 'L'
or (M) if SIDE = 'R'
WORK is not referenced if H has order < 11.```
Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 119 of file slarfx.f.

## Author

Generated automatically by Doxygen for LAPACK from the source code.

## Referenced By

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

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