SRC/clarf.f(3) Library Functions Manual SRC/clarf.f(3)

SRC/clarf.f


subroutine clarf (side, m, n, v, incv, tau, c, ldc, work)
CLARF applies an elementary reflector to a general rectangular matrix.

CLARF applies an elementary reflector to a general rectangular matrix.

Purpose:

 CLARF applies a complex elementary reflector H to a complex M-by-N
 matrix C, from either the left or the right. H is represented in the
 form
       H = I - tau * v * v**H
 where tau is a complex scalar and v is a complex vector.
 If tau = 0, then H is taken to be the unit matrix.
 To apply H**H (the conjugate transpose of H), supply conjg(tau) instead
 tau.

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 COMPLEX array, dimension
                     (1 + (M-1)*abs(INCV)) if SIDE = 'L'
                  or (1 + (N-1)*abs(INCV)) if SIDE = 'R'
          The vector v in the representation of H. V is not used if
          TAU = 0.

INCV

          INCV is INTEGER
          The increment between elements of v. INCV <> 0.

TAU

          TAU is COMPLEX
          The value tau in the representation of H.

C

          C is COMPLEX 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 >= max(1,M).

WORK

          WORK is COMPLEX array, dimension
                         (N) if SIDE = 'L'
                      or (M) if SIDE = 'R'

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 127 of file clarf.f.

Generated automatically by Doxygen for LAPACK from the source code.

Version 3.12.0 LAPACK