Scroll to navigation

sorgr2.f(3) LAPACK sorgr2.f(3)

NAME

sorgr2.f -

SYNOPSIS

Functions/Subroutines


subroutine sorgr2 (M, N, K, A, LDA, TAU, WORK, INFO)
 
SORGR2 generates all or part of the orthogonal matrix Q from an RQ factorization determined by sgerqf (unblocked algorithm).

Function/Subroutine Documentation

subroutine sorgr2 (integerM, integerN, integerK, real, dimension( lda, * )A, integerLDA, real, dimension( * )TAU, real, dimension( * )WORK, integerINFO)

SORGR2 generates all or part of the orthogonal matrix Q from an RQ factorization determined by sgerqf (unblocked algorithm).
Purpose: 
 SORGR2 generates an m by n real 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(2) . . . H(k)


 as returned by SGERQF.
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 REAL 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 SGERQF 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 REAL array, dimension (K)
          TAU(i) must contain the scalar factor of the elementary
          reflector H(i), as returned by SGERQF.
WORK 
          WORK is REAL 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 sorgr2.f.

Author

Generated automatically by Doxygen for LAPACK from the source code.
Wed Oct 15 2014 Version 3.4.2