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)

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