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Diffstat (limited to 'src/lib/lapack/dorglq.f')
-rw-r--r-- | src/lib/lapack/dorglq.f | 215 |
1 files changed, 0 insertions, 215 deletions
diff --git a/src/lib/lapack/dorglq.f b/src/lib/lapack/dorglq.f deleted file mode 100644 index e4f58c96..00000000 --- a/src/lib/lapack/dorglq.f +++ /dev/null @@ -1,215 +0,0 @@ - SUBROUTINE DORGLQ( M, N, K, A, LDA, TAU, WORK, LWORK, INFO ) -* -* -- LAPACK routine (version 3.1) -- -* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. -* November 2006 -* -* .. Scalar Arguments .. - INTEGER INFO, K, LDA, LWORK, M, N -* .. -* .. Array Arguments .. - DOUBLE PRECISION A( LDA, * ), TAU( * ), WORK( * ) -* .. -* -* Purpose -* ======= -* -* DORGLQ generates an M-by-N real matrix Q with orthonormal rows, -* which is defined as the first M rows of a product of K elementary -* reflectors of order N -* -* Q = H(k) . . . H(2) H(1) -* -* as returned by DGELQF. -* -* Arguments -* ========= -* -* M (input) INTEGER -* The number of rows of the matrix Q. M >= 0. -* -* N (input) INTEGER -* The number of columns of the matrix Q. N >= M. -* -* K (input) INTEGER -* The number of elementary reflectors whose product defines the -* matrix Q. M >= K >= 0. -* -* A (input/output) DOUBLE PRECISION array, dimension (LDA,N) -* On entry, the i-th row must contain the vector which defines -* the elementary reflector H(i), for i = 1,2,...,k, as returned -* by DGELQF in the first k rows of its array argument A. -* On exit, the M-by-N matrix Q. -* -* LDA (input) INTEGER -* The first dimension of the array A. LDA >= max(1,M). -* -* TAU (input) DOUBLE PRECISION array, dimension (K) -* TAU(i) must contain the scalar factor of the elementary -* reflector H(i), as returned by DGELQF. -* -* WORK (workspace/output) DOUBLE PRECISION array, dimension (MAX(1,LWORK)) -* On exit, if INFO = 0, WORK(1) returns the optimal LWORK. -* -* LWORK (input) INTEGER -* The dimension of the array WORK. LWORK >= max(1,M). -* For optimum performance LWORK >= M*NB, 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 (output) INTEGER -* = 0: successful exit -* < 0: if INFO = -i, the i-th argument has an illegal value -* -* ===================================================================== -* -* .. Parameters .. - DOUBLE PRECISION ZERO - PARAMETER ( ZERO = 0.0D+0 ) -* .. -* .. Local Scalars .. - LOGICAL LQUERY - INTEGER I, IB, IINFO, IWS, J, KI, KK, L, LDWORK, - $ LWKOPT, NB, NBMIN, NX -* .. -* .. External Subroutines .. - EXTERNAL DLARFB, DLARFT, DORGL2, XERBLA -* .. -* .. Intrinsic Functions .. - INTRINSIC MAX, MIN -* .. -* .. External Functions .. - INTEGER ILAENV - EXTERNAL ILAENV -* .. -* .. Executable Statements .. -* -* Test the input arguments -* - INFO = 0 - NB = ILAENV( 1, 'DORGLQ', ' ', M, N, K, -1 ) - LWKOPT = MAX( 1, M )*NB - WORK( 1 ) = LWKOPT - LQUERY = ( LWORK.EQ.-1 ) - IF( M.LT.0 ) THEN - INFO = -1 - ELSE IF( N.LT.M ) THEN - INFO = -2 - ELSE IF( K.LT.0 .OR. K.GT.M ) THEN - INFO = -3 - ELSE IF( LDA.LT.MAX( 1, M ) ) THEN - INFO = -5 - ELSE IF( LWORK.LT.MAX( 1, M ) .AND. .NOT.LQUERY ) THEN - INFO = -8 - END IF - IF( INFO.NE.0 ) THEN - CALL XERBLA( 'DORGLQ', -INFO ) - RETURN - ELSE IF( LQUERY ) THEN - RETURN - END IF -* -* Quick return if possible -* - IF( M.LE.0 ) THEN - WORK( 1 ) = 1 - RETURN - END IF -* - NBMIN = 2 - NX = 0 - IWS = M - IF( NB.GT.1 .AND. NB.LT.K ) THEN -* -* Determine when to cross over from blocked to unblocked code. -* - NX = MAX( 0, ILAENV( 3, 'DORGLQ', ' ', M, N, K, -1 ) ) - IF( NX.LT.K ) THEN -* -* Determine if workspace is large enough for blocked code. -* - LDWORK = M - IWS = LDWORK*NB - IF( LWORK.LT.IWS ) THEN -* -* Not enough workspace to use optimal NB: reduce NB and -* determine the minimum value of NB. -* - NB = LWORK / LDWORK - NBMIN = MAX( 2, ILAENV( 2, 'DORGLQ', ' ', M, N, K, -1 ) ) - END IF - END IF - END IF -* - IF( NB.GE.NBMIN .AND. NB.LT.K .AND. NX.LT.K ) THEN -* -* Use blocked code after the last block. -* The first kk rows are handled by the block method. -* - KI = ( ( K-NX-1 ) / NB )*NB - KK = MIN( K, KI+NB ) -* -* Set A(kk+1:m,1:kk) to zero. -* - DO 20 J = 1, KK - DO 10 I = KK + 1, M - A( I, J ) = ZERO - 10 CONTINUE - 20 CONTINUE - ELSE - KK = 0 - END IF -* -* Use unblocked code for the last or only block. -* - IF( KK.LT.M ) - $ CALL DORGL2( M-KK, N-KK, K-KK, A( KK+1, KK+1 ), LDA, - $ TAU( KK+1 ), WORK, IINFO ) -* - IF( KK.GT.0 ) THEN -* -* Use blocked code -* - DO 50 I = KI + 1, 1, -NB - IB = MIN( NB, K-I+1 ) - IF( I+IB.LE.M ) THEN -* -* Form the triangular factor of the block reflector -* H = H(i) H(i+1) . . . H(i+ib-1) -* - CALL DLARFT( 'Forward', 'Rowwise', N-I+1, IB, A( I, I ), - $ LDA, TAU( I ), WORK, LDWORK ) -* -* Apply H' to A(i+ib:m,i:n) from the right -* - CALL DLARFB( 'Right', 'Transpose', 'Forward', 'Rowwise', - $ M-I-IB+1, N-I+1, IB, A( I, I ), LDA, WORK, - $ LDWORK, A( I+IB, I ), LDA, WORK( IB+1 ), - $ LDWORK ) - END IF -* -* Apply H' to columns i:n of current block -* - CALL DORGL2( IB, N-I+1, IB, A( I, I ), LDA, TAU( I ), WORK, - $ IINFO ) -* -* Set columns 1:i-1 of current block to zero -* - DO 40 J = 1, I - 1 - DO 30 L = I, I + IB - 1 - A( L, J ) = ZERO - 30 CONTINUE - 40 CONTINUE - 50 CONTINUE - END IF -* - WORK( 1 ) = IWS - RETURN -* -* End of DORGLQ -* - END |