sgeqrt2.f man page on DragonFly

Printed from http://www.polarhome.com/service/man/?qf=sgeqrt2.f&af=0&tf=2&of=DragonFly

sgeqrt2.f(3)			    LAPACK			  sgeqrt2.f(3)

NAME
       sgeqrt2.f -

SYNOPSIS
   Functions/Subroutines
       subroutine sgeqrt2 (M, N, A, LDA, T, LDT, INFO)
	   SGEQRT2 computes a QR factorization of a general real or complex
	   matrix using the compact WY representation of Q.

Function/Subroutine Documentation
   subroutine sgeqrt2 (integerM, integerN, real, dimension( lda, * )A,
       integerLDA, real, dimension( ldt, * )T, integerLDT, integerINFO)
       SGEQRT2 computes a QR factorization of a general real or complex matrix
       using the compact WY representation of Q.

       Purpose:

	    SGEQRT2 computes a QR factorization of a real M-by-N matrix A,
	    using the compact WY representation of Q.

       Parameters:
	   M

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

	   N

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

	   A

		     A is REAL array, dimension (LDA,N)
		     On entry, the real M-by-N matrix A.  On exit, the elements on and
		     above the diagonal contain the N-by-N upper triangular matrix R; the
		     elements below the diagonal are the columns of V.	See below for
		     further details.

	   LDA

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

	   T

		     T is REAL array, dimension (LDT,N)
		     The N-by-N upper triangular factor of the block reflector.
		     The elements on and above the diagonal contain the block
		     reflector T; the elements below the diagonal are not used.
		     See below for further details.

	   LDT

		     LDT is INTEGER
		     The leading dimension of the array T.  LDT >= max(1,N).

	   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:
	   September 2012

       Further Details:

	     The matrix V stores the elementary reflectors H(i) in the i-th column
	     below the diagonal. For example, if M=5 and N=3, the matrix V is

			  V = (	 1	 )
			      ( v1  1	 )
			      ( v1 v2  1 )
			      ( v1 v2 v3 )
			      ( v1 v2 v3 )

	     where the vi's represent the vectors which define H(i), which are returned
	     in the matrix A.  The 1's along the diagonal of V are not stored in A.  The
	     block reflector H is then given by

			  H = I - V * T * V**T

	     where V**T is the transpose of V.

       Definition at line 128 of file sgeqrt2.f.

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

Version 3.4.2			Sat Nov 16 2013			  sgeqrt2.f(3)
[top]

List of man pages available for DragonFly

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net