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CentOS 7.0 - man page for cungr2 (centos section 3)

cungr2.f(3)							      LAPACK							       cungr2.f(3)

NAME
cungr2.f -
SYNOPSIS
Functions/Subroutines subroutine cungr2 (M, N, K, A, LDA, TAU, WORK, INFO) CUNGR2 generates all or part of the unitary matrix Q from an RQ factorization determined by cgerqf (unblocked algorithm). Function/Subroutine Documentation subroutine cungr2 (integerM, integerN, integerK, complex, dimension( lda, * )A, integerLDA, complex, dimension( * )TAU, complex, dimension( * )WORK, integerINFO) CUNGR2 generates all or part of the unitary matrix Q from an RQ factorization determined by cgerqf (unblocked algorithm). Purpose: CUNGR2 generates an m by n complex matrix Q with orthonormal rows, which is defined as the last m rows of a product of k elementary reflectors of order n Q = H(1)**H H(2)**H . . . H(k)**H as returned by CGERQF. Parameters: M M is INTEGER The number of rows of the matrix Q. M >= 0. N N is INTEGER The number of columns of the matrix Q. N >= M. K K is INTEGER The number of elementary reflectors whose product defines the matrix Q. M >= K >= 0. A A is COMPLEX array, dimension (LDA,N) On entry, the (m-k+i)-th row must contain the vector which defines the elementary reflector H(i), for i = 1,2,...,k, as returned by CGERQF in the last k rows of its array argument A. On exit, the m-by-n matrix Q. LDA LDA is INTEGER The first dimension of the array A. LDA >= max(1,M). TAU TAU is COMPLEX array, dimension (K) TAU(i) must contain the scalar factor of the elementary reflector H(i), as returned by CGERQF. WORK WORK is COMPLEX array, dimension (M) INFO INFO is INTEGER = 0: successful exit < 0: if INFO = -i, the i-th argument has an illegal value Author: Univ. of Tennessee Univ. of California Berkeley Univ. of Colorado Denver NAG Ltd. Date: September 2012 Definition at line 115 of file cungr2.f. Author Generated automatically by Doxygen for LAPACK from the source code. Version 3.4.2 Tue Sep 25 2012 cungr2.f(3)