cupgtr.f man page

cupgtr.f

Synopsis

Functions/Subroutines

subroutine cupgtr (UPLO, N, AP, TAU, Q, LDQ, WORK, INFO)
CUPGTR

Function/Subroutine Documentation

subroutine cupgtr (character UPLO, integer N, complex, dimension( * ) AP, complex, dimension( * ) TAU, complex, dimension( ldq, * ) Q, integer LDQ, complex, dimension( * ) WORK, integer INFO)

CUPGTR  

Purpose:

 CUPGTR generates a complex unitary matrix Q which is defined as the
 product of n-1 elementary reflectors H(i) of order n, as returned by
 CHPTRD using packed storage:

 if UPLO = 'U', Q = H(n-1) . . . H(2) H(1),

 if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).
Parameters:

UPLO

          UPLO is CHARACTER*1
          = 'U': Upper triangular packed storage used in previous
                 call to CHPTRD;
          = 'L': Lower triangular packed storage used in previous
                 call to CHPTRD.

N

          N is INTEGER
          The order of the matrix Q. N >= 0.

AP

          AP is COMPLEX array, dimension (N*(N+1)/2)
          The vectors which define the elementary reflectors, as
          returned by CHPTRD.

TAU

          TAU is COMPLEX array, dimension (N-1)
          TAU(i) must contain the scalar factor of the elementary
          reflector H(i), as returned by CHPTRD.

Q

          Q is COMPLEX array, dimension (LDQ,N)
          The N-by-N unitary matrix Q.

LDQ

          LDQ is INTEGER
          The leading dimension of the array Q. LDQ >= max(1,N).

WORK

          WORK is COMPLEX array, dimension (N-1)

INFO

          INFO is INTEGER
          = 0:  successful exit
          < 0:  if INFO = -i, the i-th argument had an illegal value
Author:

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Date:

December 2016

Definition at line 116 of file cupgtr.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.

Referenced By

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

Tue Nov 14 2017 Version 3.8.0 LAPACK