added lapack 3.7.0 with latest patches from git
This commit is contained in:
232
lapack-netlib/SRC/DEPRECATED/dtzrqf.f
Normal file
232
lapack-netlib/SRC/DEPRECATED/dtzrqf.f
Normal file
@@ -0,0 +1,232 @@
|
||||
*> \brief \b DTZRQF
|
||||
*
|
||||
* =========== DOCUMENTATION ===========
|
||||
*
|
||||
* Online html documentation available at
|
||||
* http://www.netlib.org/lapack/explore-html/
|
||||
*
|
||||
*> \htmlonly
|
||||
*> Download DTZRQF + dependencies
|
||||
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/dtzrqf.f">
|
||||
*> [TGZ]</a>
|
||||
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/dtzrqf.f">
|
||||
*> [ZIP]</a>
|
||||
*> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/dtzrqf.f">
|
||||
*> [TXT]</a>
|
||||
*> \endhtmlonly
|
||||
*
|
||||
* Definition:
|
||||
* ===========
|
||||
*
|
||||
* SUBROUTINE DTZRQF( M, N, A, LDA, TAU, INFO )
|
||||
*
|
||||
* .. Scalar Arguments ..
|
||||
* INTEGER INFO, LDA, M, N
|
||||
* ..
|
||||
* .. Array Arguments ..
|
||||
* DOUBLE PRECISION A( LDA, * ), TAU( * )
|
||||
* ..
|
||||
*
|
||||
*
|
||||
*> \par Purpose:
|
||||
* =============
|
||||
*>
|
||||
*> \verbatim
|
||||
*>
|
||||
*> This routine is deprecated and has been replaced by routine DTZRZF.
|
||||
*>
|
||||
*> DTZRQF reduces the M-by-N ( M<=N ) real upper trapezoidal matrix A
|
||||
*> to upper triangular form by means of orthogonal transformations.
|
||||
*>
|
||||
*> The upper trapezoidal matrix A is factored as
|
||||
*>
|
||||
*> A = ( R 0 ) * Z,
|
||||
*>
|
||||
*> where Z is an N-by-N orthogonal matrix and R is an M-by-M upper
|
||||
*> triangular matrix.
|
||||
*> \endverbatim
|
||||
*
|
||||
* Arguments:
|
||||
* ==========
|
||||
*
|
||||
*> \param[in] M
|
||||
*> \verbatim
|
||||
*> M is INTEGER
|
||||
*> The number of rows of the matrix A. M >= 0.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in] N
|
||||
*> \verbatim
|
||||
*> N is INTEGER
|
||||
*> The number of columns of the matrix A. N >= M.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in,out] A
|
||||
*> \verbatim
|
||||
*> A is DOUBLE PRECISION array, dimension (LDA,N)
|
||||
*> On entry, the leading M-by-N upper trapezoidal part of the
|
||||
*> array A must contain the matrix to be factorized.
|
||||
*> On exit, the leading M-by-M upper triangular part of A
|
||||
*> contains the upper triangular matrix R, and elements M+1 to
|
||||
*> N of the first M rows of A, with the array TAU, represent the
|
||||
*> orthogonal matrix Z as a product of M elementary reflectors.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[in] LDA
|
||||
*> \verbatim
|
||||
*> LDA is INTEGER
|
||||
*> The leading dimension of the array A. LDA >= max(1,M).
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[out] TAU
|
||||
*> \verbatim
|
||||
*> TAU is DOUBLE PRECISION array, dimension (M)
|
||||
*> The scalar factors of the elementary reflectors.
|
||||
*> \endverbatim
|
||||
*>
|
||||
*> \param[out] INFO
|
||||
*> \verbatim
|
||||
*> INFO is INTEGER
|
||||
*> = 0: successful exit
|
||||
*> < 0: if INFO = -i, the i-th argument had an illegal value
|
||||
*> \endverbatim
|
||||
*
|
||||
* Authors:
|
||||
* ========
|
||||
*
|
||||
*> \author Univ. of Tennessee
|
||||
*> \author Univ. of California Berkeley
|
||||
*> \author Univ. of Colorado Denver
|
||||
*> \author NAG Ltd.
|
||||
*
|
||||
*> \date December 2016
|
||||
*
|
||||
*> \ingroup doubleOTHERcomputational
|
||||
*
|
||||
*> \par Further Details:
|
||||
* =====================
|
||||
*>
|
||||
*> \verbatim
|
||||
*>
|
||||
*> The factorization is obtained by Householder's method. The kth
|
||||
*> transformation matrix, Z( k ), which is used to introduce zeros into
|
||||
*> the ( m - k + 1 )th row of A, is given in the form
|
||||
*>
|
||||
*> Z( k ) = ( I 0 ),
|
||||
*> ( 0 T( k ) )
|
||||
*>
|
||||
*> where
|
||||
*>
|
||||
*> T( k ) = I - tau*u( k )*u( k )**T, u( k ) = ( 1 ),
|
||||
*> ( 0 )
|
||||
*> ( z( k ) )
|
||||
*>
|
||||
*> tau is a scalar and z( k ) is an ( n - m ) element vector.
|
||||
*> tau and z( k ) are chosen to annihilate the elements of the kth row
|
||||
*> of X.
|
||||
*>
|
||||
*> The scalar tau is returned in the kth element of TAU and the vector
|
||||
*> u( k ) in the kth row of A, such that the elements of z( k ) are
|
||||
*> in a( k, m + 1 ), ..., a( k, n ). The elements of R are returned in
|
||||
*> the upper triangular part of A.
|
||||
*>
|
||||
*> Z is given by
|
||||
*>
|
||||
*> Z = Z( 1 ) * Z( 2 ) * ... * Z( m ).
|
||||
*> \endverbatim
|
||||
*>
|
||||
* =====================================================================
|
||||
SUBROUTINE DTZRQF( M, N, A, LDA, TAU, INFO )
|
||||
*
|
||||
* -- LAPACK computational routine (version 3.7.0) --
|
||||
* -- LAPACK is a software package provided by Univ. of Tennessee, --
|
||||
* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
|
||||
* December 2016
|
||||
*
|
||||
* .. Scalar Arguments ..
|
||||
INTEGER INFO, LDA, M, N
|
||||
* ..
|
||||
* .. Array Arguments ..
|
||||
DOUBLE PRECISION A( LDA, * ), TAU( * )
|
||||
* ..
|
||||
*
|
||||
* =====================================================================
|
||||
*
|
||||
* .. Parameters ..
|
||||
DOUBLE PRECISION ONE, ZERO
|
||||
PARAMETER ( ONE = 1.0D+0, ZERO = 0.0D+0 )
|
||||
* ..
|
||||
* .. Local Scalars ..
|
||||
INTEGER I, K, M1
|
||||
* ..
|
||||
* .. Intrinsic Functions ..
|
||||
INTRINSIC MAX, MIN
|
||||
* ..
|
||||
* .. External Subroutines ..
|
||||
EXTERNAL DAXPY, DCOPY, DGEMV, DGER, DLARFG, XERBLA
|
||||
* ..
|
||||
* .. Executable Statements ..
|
||||
*
|
||||
* Test the input parameters.
|
||||
*
|
||||
INFO = 0
|
||||
IF( M.LT.0 ) THEN
|
||||
INFO = -1
|
||||
ELSE IF( N.LT.M ) THEN
|
||||
INFO = -2
|
||||
ELSE IF( LDA.LT.MAX( 1, M ) ) THEN
|
||||
INFO = -4
|
||||
END IF
|
||||
IF( INFO.NE.0 ) THEN
|
||||
CALL XERBLA( 'DTZRQF', -INFO )
|
||||
RETURN
|
||||
END IF
|
||||
*
|
||||
* Perform the factorization.
|
||||
*
|
||||
IF( M.EQ.0 )
|
||||
$ RETURN
|
||||
IF( M.EQ.N ) THEN
|
||||
DO 10 I = 1, N
|
||||
TAU( I ) = ZERO
|
||||
10 CONTINUE
|
||||
ELSE
|
||||
M1 = MIN( M+1, N )
|
||||
DO 20 K = M, 1, -1
|
||||
*
|
||||
* Use a Householder reflection to zero the kth row of A.
|
||||
* First set up the reflection.
|
||||
*
|
||||
CALL DLARFG( N-M+1, A( K, K ), A( K, M1 ), LDA, TAU( K ) )
|
||||
*
|
||||
IF( ( TAU( K ).NE.ZERO ) .AND. ( K.GT.1 ) ) THEN
|
||||
*
|
||||
* We now perform the operation A := A*P( k ).
|
||||
*
|
||||
* Use the first ( k - 1 ) elements of TAU to store a( k ),
|
||||
* where a( k ) consists of the first ( k - 1 ) elements of
|
||||
* the kth column of A. Also let B denote the first
|
||||
* ( k - 1 ) rows of the last ( n - m ) columns of A.
|
||||
*
|
||||
CALL DCOPY( K-1, A( 1, K ), 1, TAU, 1 )
|
||||
*
|
||||
* Form w = a( k ) + B*z( k ) in TAU.
|
||||
*
|
||||
CALL DGEMV( 'No transpose', K-1, N-M, ONE, A( 1, M1 ),
|
||||
$ LDA, A( K, M1 ), LDA, ONE, TAU, 1 )
|
||||
*
|
||||
* Now form a( k ) := a( k ) - tau*w
|
||||
* and B := B - tau*w*z( k )**T.
|
||||
*
|
||||
CALL DAXPY( K-1, -TAU( K ), TAU, 1, A( 1, K ), 1 )
|
||||
CALL DGER( K-1, N-M, -TAU( K ), TAU, 1, A( K, M1 ), LDA,
|
||||
$ A( 1, M1 ), LDA )
|
||||
END IF
|
||||
20 CONTINUE
|
||||
END IF
|
||||
*
|
||||
RETURN
|
||||
*
|
||||
* End of DTZRQF
|
||||
*
|
||||
END
|
||||
Reference in New Issue
Block a user