debian man page for dgerq2

dgerq2.f(3)							      LAPACK							       dgerq2.f(3)

NAME
       dgerq2.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dgerq2 (M, N, A, LDA, TAU, WORK, INFO)
	   DGERQ2

Function/Subroutine Documentation
   subroutine dgerq2 (integerM, integerN, double precision, dimension( lda, * )A, integerLDA, double precision, dimension( * )TAU, double
       precision, dimension( * )WORK, integerINFO)
       DGERQ2

       Purpose:

	    DGERQ2 computes an RQ factorization of a real m by n matrix A:
	    A = R * Q.

       Parameters:
	   M

		     M is INTEGER
		     The number of rows of the matrix A.  M >= 0.

	   N

		     N is INTEGER
		     The number of columns of the matrix A.  N >= 0.

	   A

		     A is DOUBLE PRECISION array, dimension (LDA,N)
		     On entry, the m by n matrix A.
		     On exit, if m <= n, the upper triangle of the subarray
		     A(1:m,n-m+1:n) contains the m by m upper triangular matrix R;
		     if m >= n, the elements on and above the (m-n)-th subdiagonal
		     contain the m by n upper trapezoidal matrix R; the remaining
		     elements, with the array TAU, represent the orthogonal matrix
		     Q as a product of elementary reflectors (see Further
		     Details).

	   LDA

		     LDA is INTEGER
		     The leading dimension of the array A.  LDA >= max(1,M).

	   TAU

		     TAU is DOUBLE PRECISION array, dimension (min(M,N))
		     The scalar factors of the elementary reflectors (see Further
		     Details).

	   WORK

		     WORK is DOUBLE PRECISION array, dimension (M)

	   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

       Further Details:

	     The matrix Q is represented as a product of elementary reflectors

		Q = H(1) H(2) . . . H(k), where k = min(m,n).

	     Each H(i) has the form

		H(i) = I - tau * v * v**T

	     where tau is a real scalar, and v is a real vector with
	     v(n-k+i+1:n) = 0 and v(n-k+i) = 1; v(1:n-k+i-1) is stored on exit in
	     A(m-k+i,1:n-k+i-1), and tau in TAU(i).

       Definition at line 124 of file dgerq2.f.

Author
       Generated automatically by Doxygen for LAPACK from the source code.

Version 3.4.1							  Sun May 26 2013						       dgerq2.f(3)