LAPACK  3.4.2
LAPACK: Linear Algebra PACKage
 All Files Functions Groups
zupgtr.f File Reference

Go to the source code of this file.


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

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 


Download ZUPGTR + dependencies [TGZ] [ZIP] [TXT]
 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).
          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 is INTEGER
          The order of the matrix Q. N >= 0.
          AP is COMPLEX*16 array, dimension (N*(N+1)/2)
          The vectors which define the elementary reflectors, as
          returned by ZHPTRD.
          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 is COMPLEX*16 array, dimension (LDQ,N)
          The N-by-N unitary matrix Q.
          LDQ is INTEGER
          The leading dimension of the array Q. LDQ >= max(1,N).
          WORK is COMPLEX*16 array, dimension (N-1)
          INFO is INTEGER
          = 0:  successful exit
          < 0:  if INFO = -i, the i-th argument had an illegal value
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.
November 2011

Definition at line 115 of file zupgtr.f.

Here is the call graph for this function:

Here is the caller graph for this function: