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dormtr.f(3)				      LAPACK				      dormtr.f(3)

NAME
       dormtr.f -

SYNOPSIS
   Functions/Subroutines
       subroutine dormtr (SIDE, UPLO, TRANS, M, N, A, LDA, TAU, C, LDC, WORK, LWORK, INFO)
	   DORMTR

Function/Subroutine Documentation
   subroutine dormtr (characterSIDE, characterUPLO, characterTRANS, integerM, integerN, double
       precision, dimension( lda, * )A, integerLDA, double precision, dimension( * )TAU, double
       precision, dimension( ldc, * )C, integerLDC, double precision, dimension( * )WORK,
       integerLWORK, integerINFO)
       DORMTR

       Purpose:

	    DORMTR overwrites the general real M-by-N matrix C with

			    SIDE = 'L'	   SIDE = 'R'
	    TRANS = 'N':      Q * C	     C * Q
	    TRANS = 'T':      Q**T * C	     C * Q**T

	    where Q is a real orthogonal matrix of order nq, with nq = m if
	    SIDE = 'L' and nq = n if SIDE = 'R'. Q is defined as the product of
	    nq-1 elementary reflectors, as returned by DSYTRD:

	    if UPLO = 'U', Q = H(nq-1) . . . H(2) H(1);

	    if UPLO = 'L', Q = H(1) H(2) . . . H(nq-1).

       Parameters:
	   SIDE

		     SIDE is CHARACTER*1
		     = 'L': apply Q or Q**T from the Left;
		     = 'R': apply Q or Q**T from the Right.

	   UPLO

		     UPLO is CHARACTER*1
		     = 'U': Upper triangle of A contains elementary reflectors
			    from DSYTRD;
		     = 'L': Lower triangle of A contains elementary reflectors
			    from DSYTRD.

	   TRANS

		     TRANS is CHARACTER*1
		     = 'N':  No transpose, apply Q;
		     = 'T':  Transpose, apply Q**T.

	   M

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

	   N

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

	   A

		     A is DOUBLE PRECISION array, dimension
					  (LDA,M) if SIDE = 'L'
					  (LDA,N) if SIDE = 'R'
		     The vectors which define the elementary reflectors, as
		     returned by DSYTRD.

	   LDA

		     LDA is INTEGER
		     The leading dimension of the array A.
		     LDA >= max(1,M) if SIDE = 'L'; LDA >= max(1,N) if SIDE = 'R'.

	   TAU

		     TAU is DOUBLE PRECISION array, dimension
					  (M-1) if SIDE = 'L'
					  (N-1) if SIDE = 'R'
		     TAU(i) must contain the scalar factor of the elementary
		     reflector H(i), as returned by DSYTRD.

	   C

		     C is DOUBLE PRECISION array, dimension (LDC,N)
		     On entry, the M-by-N matrix C.
		     On exit, C is overwritten by Q*C or Q**T*C or C*Q**T or C*Q.

	   LDC

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

	   WORK

		     WORK is DOUBLE PRECISION array, dimension (MAX(1,LWORK))
		     On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

	   LWORK

		     LWORK is INTEGER
		     The dimension of the array WORK.
		     If SIDE = 'L', LWORK >= max(1,N);
		     if SIDE = 'R', LWORK >= max(1,M).
		     For optimum performance LWORK >= N*NB if SIDE = 'L', and
		     LWORK >= M*NB if SIDE = 'R', where NB is the optimal
		     blocksize.

		     If LWORK = -1, then a workspace query is assumed; the routine
		     only calculates the optimal size of the WORK array, returns
		     this value as the first entry of the WORK array, and no error
		     message related to LWORK is issued by XERBLA.

	   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

       Definition at line 171 of file dormtr.f.

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

Version 3.4.2				 Tue Sep 25 2012			      dormtr.f(3)
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