zupgtr.f

Section: LAPACK (3)
Updated: Tue Nov 14 2017
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NAME

zupgtr.f  

SYNOPSIS


 

Functions/Subroutines


subroutine zupgtr (UPLO, N, AP, TAU, Q, LDQ, WORK, INFO)
ZUPGTR  

Function/Subroutine Documentation

 

subroutine zupgtr (character UPLO, integer N, complex*16, dimension( * ) AP, complex*16, dimension( * ) TAU, complex*16, dimension( ldq, * ) Q, integer LDQ, complex*16, dimension( * ) WORK, integer INFO)

ZUPGTR

Purpose: 

 ZUPGTR 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
 ZHPTRD 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 ZHPTRD;
          = 'L': Lower triangular packed storage used in previous
                 call to ZHPTRD.


N 

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


AP 

          AP is COMPLEX*16 array, dimension (N*(N+1)/2)
          The vectors which define the elementary reflectors, as
          returned by ZHPTRD.


TAU 

          TAU is COMPLEX*16 array, dimension (N-1)
          TAU(i) must contain the scalar factor of the elementary
          reflector H(i), as returned by ZHPTRD.


Q 

          Q is COMPLEX*16 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*16 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 zupgtr.f.  

Author

Generated automatically by Doxygen for LAPACK from the source code.

 

Index

NAME
SYNOPSIS
Functions/Subroutines
Function/Subroutine Documentation
subroutine zupgtr (character UPLO, integer N, complex*16, dimension( * ) AP, complex*16, dimension( * ) TAU, complex*16, dimension( ldq, * ) Q, integer LDQ, complex*16, dimension( * ) WORK, integer INFO)
Author