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.

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.

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

November 2017