clarfgp.f man page

clarfgp.f

Synopsis

Functions/Subroutines

subroutine clarfgp (N, ALPHA, X, INCX, TAU)
CLARFGP generates an elementary reflector (Householder matrix) with non-negative beta.

Function/Subroutine Documentation

subroutine clarfgp (integer N, complex ALPHA, complex, dimension( * ) X, integer INCX, complex TAU)

CLARFGP generates an elementary reflector (Householder matrix) with non-negative beta.  

Purpose:

 CLARFGP generates a complex elementary reflector H of order n, such
 that

       H**H * ( alpha ) = ( beta ),   H**H * H = I.
              (   x   )   (   0  )

 where alpha and beta are scalars, beta is real and non-negative, and
 x is an (n-1)-element complex vector.  H is represented in the form

       H = I - tau * ( 1 ) * ( 1 v**H ) ,
                     ( v )

 where tau is a complex scalar and v is a complex (n-1)-element
 vector. Note that H is not hermitian.

 If the elements of x are all zero and alpha is real, then tau = 0
 and H is taken to be the unit matrix.
Parameters:

N

          N is INTEGER
          The order of the elementary reflector.

ALPHA

          ALPHA is COMPLEX
          On entry, the value alpha.
          On exit, it is overwritten with the value beta.

X

          X is COMPLEX array, dimension
                         (1+(N-2)*abs(INCX))
          On entry, the vector x.
          On exit, it is overwritten with the vector v.

INCX

          INCX is INTEGER
          The increment between elements of X. INCX > 0.

TAU

          TAU is COMPLEX
          The value tau.
Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

November 2017

Definition at line 106 of file clarfgp.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

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

Tue Nov 14 2017 Version 3.8.0 LAPACK