zupgtr.f (3) Linux Manual Page

zupgtr.f –

Synopsis

Functions/Subroutines

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

Function/Subroutine Documentation

subroutine zupgtr (characterUPLO, integerN, complex*16, dimension( * )AP, complex*16, dimension( * )TAU, complex*16, dimension( ldq, * )Q, integerLDQ, complex*16, dimension( * )WORK, integerINFO)

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:

November 2011

Definition at line 115 of file zupgtr.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.