root / src / lapack / double / dlarfb.f @ 2
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SUBROUTINE DLARFB( SIDE, TRANS, DIRECT, STOREV, M, N, K, V, LDV, |
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$ T, LDT, C, LDC, WORK, LDWORK ) |
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IMPLICIT NONE |
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* |
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* -- LAPACK auxiliary routine (version 3.2) -- |
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* -- LAPACK is a software package provided by Univ. of Tennessee, -- |
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* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- |
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* November 2006 |
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* |
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* .. Scalar Arguments .. |
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CHARACTER DIRECT, SIDE, STOREV, TRANS |
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INTEGER K, LDC, LDT, LDV, LDWORK, M, N |
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* .. |
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* .. Array Arguments .. |
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DOUBLE PRECISION C( LDC, * ), T( LDT, * ), V( LDV, * ), |
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$ WORK( LDWORK, * ) |
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* .. |
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* |
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* Purpose |
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* ======= |
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* |
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* DLARFB applies a real block reflector H or its transpose H' to a |
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* real m by n matrix C, from either the left or the right. |
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* |
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* Arguments |
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* ========= |
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* |
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* SIDE (input) CHARACTER*1 |
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* = 'L': apply H or H' from the Left |
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* = 'R': apply H or H' from the Right |
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* |
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* TRANS (input) CHARACTER*1 |
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* = 'N': apply H (No transpose) |
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* = 'T': apply H' (Transpose) |
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* |
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* DIRECT (input) CHARACTER*1 |
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* Indicates how H is formed from a product of elementary |
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* reflectors |
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* = 'F': H = H(1) H(2) . . . H(k) (Forward) |
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* = 'B': H = H(k) . . . H(2) H(1) (Backward) |
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* |
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* STOREV (input) CHARACTER*1 |
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* Indicates how the vectors which define the elementary |
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* reflectors are stored: |
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* = 'C': Columnwise |
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* = 'R': Rowwise |
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* |
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* M (input) INTEGER |
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* The number of rows of the matrix C. |
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* |
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* N (input) INTEGER |
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* The number of columns of the matrix C. |
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* |
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* K (input) INTEGER |
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* The order of the matrix T (= the number of elementary |
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* reflectors whose product defines the block reflector). |
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* |
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* V (input) DOUBLE PRECISION array, dimension |
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* (LDV,K) if STOREV = 'C' |
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* (LDV,M) if STOREV = 'R' and SIDE = 'L' |
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* (LDV,N) if STOREV = 'R' and SIDE = 'R' |
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* The matrix V. See further details. |
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* |
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* LDV (input) INTEGER |
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* The leading dimension of the array V. |
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* If STOREV = 'C' and SIDE = 'L', LDV >= max(1,M); |
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* if STOREV = 'C' and SIDE = 'R', LDV >= max(1,N); |
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* if STOREV = 'R', LDV >= K. |
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* |
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* T (input) DOUBLE PRECISION array, dimension (LDT,K) |
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* The triangular k by k matrix T in the representation of the |
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* block reflector. |
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* |
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* LDT (input) INTEGER |
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* The leading dimension of the array T. LDT >= K. |
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* |
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* C (input/output) DOUBLE PRECISION array, dimension (LDC,N) |
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* On entry, the m by n matrix C. |
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* On exit, C is overwritten by H*C or H'*C or C*H or C*H'. |
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* |
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* LDC (input) INTEGER |
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* The leading dimension of the array C. LDA >= max(1,M). |
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* |
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* WORK (workspace) DOUBLE PRECISION array, dimension (LDWORK,K) |
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* |
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* LDWORK (input) INTEGER |
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* The leading dimension of the array WORK. |
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* If SIDE = 'L', LDWORK >= max(1,N); |
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* if SIDE = 'R', LDWORK >= max(1,M). |
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* |
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* ===================================================================== |
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* |
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* .. Parameters .. |
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DOUBLE PRECISION ONE |
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PARAMETER ( ONE = 1.0D+0 ) |
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* .. |
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* .. Local Scalars .. |
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CHARACTER TRANST |
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INTEGER I, J, LASTV, LASTC |
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* .. |
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* .. External Functions .. |
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LOGICAL LSAME |
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INTEGER ILADLR, ILADLC |
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EXTERNAL LSAME, ILADLR, ILADLC |
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* .. |
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* .. External Subroutines .. |
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EXTERNAL DCOPY, DGEMM, DTRMM |
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* .. |
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* .. Executable Statements .. |
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* |
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* Quick return if possible |
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* |
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IF( M.LE.0 .OR. N.LE.0 ) |
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$ RETURN |
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* |
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IF( LSAME( TRANS, 'N' ) ) THEN |
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TRANST = 'T' |
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ELSE |
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TRANST = 'N' |
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END IF |
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* |
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IF( LSAME( STOREV, 'C' ) ) THEN |
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* |
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IF( LSAME( DIRECT, 'F' ) ) THEN |
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* |
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* Let V = ( V1 ) (first K rows) |
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* ( V2 ) |
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* where V1 is unit lower triangular. |
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* |
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IF( LSAME( SIDE, 'L' ) ) THEN |
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* |
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* Form H * C or H' * C where C = ( C1 ) |
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* ( C2 ) |
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* |
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LASTV = MAX( K, ILADLR( M, K, V, LDV ) ) |
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LASTC = ILADLC( LASTV, N, C, LDC ) |
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* |
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* W := C' * V = (C1'*V1 + C2'*V2) (stored in WORK) |
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* |
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* W := C1' |
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* |
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DO 10 J = 1, K |
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CALL DCOPY( LASTC, C( J, 1 ), LDC, WORK( 1, J ), 1 ) |
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10 CONTINUE |
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* |
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* W := W * V1 |
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* |
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CALL DTRMM( 'Right', 'Lower', 'No transpose', 'Unit', |
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$ LASTC, K, ONE, V, LDV, WORK, LDWORK ) |
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IF( LASTV.GT.K ) THEN |
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* |
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* W := W + C2'*V2 |
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* |
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CALL DGEMM( 'Transpose', 'No transpose', |
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$ LASTC, K, LASTV-K, |
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$ ONE, C( K+1, 1 ), LDC, V( K+1, 1 ), LDV, |
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$ ONE, WORK, LDWORK ) |
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END IF |
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* |
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* W := W * T' or W * T |
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* |
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CALL DTRMM( 'Right', 'Upper', TRANST, 'Non-unit', |
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$ LASTC, K, ONE, T, LDT, WORK, LDWORK ) |
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* |
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* C := C - V * W' |
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* |
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IF( LASTV.GT.K ) THEN |
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* |
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* C2 := C2 - V2 * W' |
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* |
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CALL DGEMM( 'No transpose', 'Transpose', |
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$ LASTV-K, LASTC, K, |
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$ -ONE, V( K+1, 1 ), LDV, WORK, LDWORK, ONE, |
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$ C( K+1, 1 ), LDC ) |
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END IF |
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* |
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* W := W * V1' |
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* |
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CALL DTRMM( 'Right', 'Lower', 'Transpose', 'Unit', |
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$ LASTC, K, ONE, V, LDV, WORK, LDWORK ) |
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* |
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* C1 := C1 - W' |
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* |
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DO 30 J = 1, K |
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DO 20 I = 1, LASTC |
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C( J, I ) = C( J, I ) - WORK( I, J ) |
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20 CONTINUE |
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30 CONTINUE |
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* |
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ELSE IF( LSAME( SIDE, 'R' ) ) THEN |
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* |
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* Form C * H or C * H' where C = ( C1 C2 ) |
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* |
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LASTV = MAX( K, ILADLR( N, K, V, LDV ) ) |
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LASTC = ILADLR( M, LASTV, C, LDC ) |
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* |
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* W := C * V = (C1*V1 + C2*V2) (stored in WORK) |
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* |
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* W := C1 |
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* |
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DO 40 J = 1, K |
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CALL DCOPY( LASTC, C( 1, J ), 1, WORK( 1, J ), 1 ) |
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40 CONTINUE |
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* |
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* W := W * V1 |
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* |
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CALL DTRMM( 'Right', 'Lower', 'No transpose', 'Unit', |
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$ LASTC, K, ONE, V, LDV, WORK, LDWORK ) |
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IF( LASTV.GT.K ) THEN |
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* |
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* W := W + C2 * V2 |
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* |
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CALL DGEMM( 'No transpose', 'No transpose', |
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$ LASTC, K, LASTV-K, |
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$ ONE, C( 1, K+1 ), LDC, V( K+1, 1 ), LDV, |
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$ ONE, WORK, LDWORK ) |
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END IF |
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* |
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* W := W * T or W * T' |
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* |
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CALL DTRMM( 'Right', 'Upper', TRANS, 'Non-unit', |
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$ LASTC, K, ONE, T, LDT, WORK, LDWORK ) |
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* |
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* C := C - W * V' |
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* |
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IF( LASTV.GT.K ) THEN |
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* |
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* C2 := C2 - W * V2' |
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* |
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CALL DGEMM( 'No transpose', 'Transpose', |
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$ LASTC, LASTV-K, K, |
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$ -ONE, WORK, LDWORK, V( K+1, 1 ), LDV, ONE, |
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$ C( 1, K+1 ), LDC ) |
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END IF |
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* |
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* W := W * V1' |
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* |
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CALL DTRMM( 'Right', 'Lower', 'Transpose', 'Unit', |
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$ LASTC, K, ONE, V, LDV, WORK, LDWORK ) |
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* |
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* C1 := C1 - W |
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* |
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DO 60 J = 1, K |
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DO 50 I = 1, LASTC |
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C( I, J ) = C( I, J ) - WORK( I, J ) |
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50 CONTINUE |
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60 CONTINUE |
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END IF |
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* |
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ELSE |
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* |
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* Let V = ( V1 ) |
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* ( V2 ) (last K rows) |
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* where V2 is unit upper triangular. |
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* |
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IF( LSAME( SIDE, 'L' ) ) THEN |
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* |
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* Form H * C or H' * C where C = ( C1 ) |
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* ( C2 ) |
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* |
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LASTV = MAX( K, ILADLR( M, K, V, LDV ) ) |
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LASTC = ILADLC( LASTV, N, C, LDC ) |
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* |
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* W := C' * V = (C1'*V1 + C2'*V2) (stored in WORK) |
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* |
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* W := C2' |
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* |
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DO 70 J = 1, K |
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CALL DCOPY( LASTC, C( LASTV-K+J, 1 ), LDC, |
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$ WORK( 1, J ), 1 ) |
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70 CONTINUE |
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* |
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* W := W * V2 |
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* |
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CALL DTRMM( 'Right', 'Upper', 'No transpose', 'Unit', |
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$ LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV, |
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$ WORK, LDWORK ) |
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IF( LASTV.GT.K ) THEN |
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* |
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* W := W + C1'*V1 |
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* |
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CALL DGEMM( 'Transpose', 'No transpose', |
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$ LASTC, K, LASTV-K, ONE, C, LDC, V, LDV, |
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$ ONE, WORK, LDWORK ) |
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END IF |
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* |
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* W := W * T' or W * T |
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* |
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CALL DTRMM( 'Right', 'Lower', TRANST, 'Non-unit', |
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$ LASTC, K, ONE, T, LDT, WORK, LDWORK ) |
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* |
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* C := C - V * W' |
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* |
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IF( LASTV.GT.K ) THEN |
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* |
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* C1 := C1 - V1 * W' |
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* |
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CALL DGEMM( 'No transpose', 'Transpose', |
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$ LASTV-K, LASTC, K, -ONE, V, LDV, WORK, LDWORK, |
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$ ONE, C, LDC ) |
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END IF |
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* |
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* W := W * V2' |
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* |
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CALL DTRMM( 'Right', 'Upper', 'Transpose', 'Unit', |
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$ LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV, |
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$ WORK, LDWORK ) |
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* |
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* C2 := C2 - W' |
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* |
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DO 90 J = 1, K |
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DO 80 I = 1, LASTC |
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C( LASTV-K+J, I ) = C( LASTV-K+J, I ) - WORK(I, J) |
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80 CONTINUE |
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90 CONTINUE |
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* |
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ELSE IF( LSAME( SIDE, 'R' ) ) THEN |
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* |
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* Form C * H or C * H' where C = ( C1 C2 ) |
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* |
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LASTV = MAX( K, ILADLR( N, K, V, LDV ) ) |
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LASTC = ILADLR( M, LASTV, C, LDC ) |
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* |
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* W := C * V = (C1*V1 + C2*V2) (stored in WORK) |
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* |
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* W := C2 |
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* |
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DO 100 J = 1, K |
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CALL DCOPY( LASTC, C( 1, N-K+J ), 1, WORK( 1, J ), 1 ) |
| 330 |
100 CONTINUE |
| 331 |
* |
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* W := W * V2 |
| 333 |
* |
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CALL DTRMM( 'Right', 'Upper', 'No transpose', 'Unit', |
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$ LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV, |
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$ WORK, LDWORK ) |
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IF( LASTV.GT.K ) THEN |
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* |
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* W := W + C1 * V1 |
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* |
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CALL DGEMM( 'No transpose', 'No transpose', |
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$ LASTC, K, LASTV-K, ONE, C, LDC, V, LDV, |
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$ ONE, WORK, LDWORK ) |
| 344 |
END IF |
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* |
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* W := W * T or W * T' |
| 347 |
* |
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CALL DTRMM( 'Right', 'Lower', TRANS, 'Non-unit', |
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$ LASTC, K, ONE, T, LDT, WORK, LDWORK ) |
| 350 |
* |
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* C := C - W * V' |
| 352 |
* |
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IF( LASTV.GT.K ) THEN |
| 354 |
* |
| 355 |
* C1 := C1 - W * V1' |
| 356 |
* |
| 357 |
CALL DGEMM( 'No transpose', 'Transpose', |
| 358 |
$ LASTC, LASTV-K, K, -ONE, WORK, LDWORK, V, LDV, |
| 359 |
$ ONE, C, LDC ) |
| 360 |
END IF |
| 361 |
* |
| 362 |
* W := W * V2' |
| 363 |
* |
| 364 |
CALL DTRMM( 'Right', 'Upper', 'Transpose', 'Unit', |
| 365 |
$ LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV, |
| 366 |
$ WORK, LDWORK ) |
| 367 |
* |
| 368 |
* C2 := C2 - W |
| 369 |
* |
| 370 |
DO 120 J = 1, K |
| 371 |
DO 110 I = 1, LASTC |
| 372 |
C( I, LASTV-K+J ) = C( I, LASTV-K+J ) - WORK(I, J) |
| 373 |
110 CONTINUE |
| 374 |
120 CONTINUE |
| 375 |
END IF |
| 376 |
END IF |
| 377 |
* |
| 378 |
ELSE IF( LSAME( STOREV, 'R' ) ) THEN |
| 379 |
* |
| 380 |
IF( LSAME( DIRECT, 'F' ) ) THEN |
| 381 |
* |
| 382 |
* Let V = ( V1 V2 ) (V1: first K columns) |
| 383 |
* where V1 is unit upper triangular. |
| 384 |
* |
| 385 |
IF( LSAME( SIDE, 'L' ) ) THEN |
| 386 |
* |
| 387 |
* Form H * C or H' * C where C = ( C1 ) |
| 388 |
* ( C2 ) |
| 389 |
* |
| 390 |
LASTV = MAX( K, ILADLC( K, M, V, LDV ) ) |
| 391 |
LASTC = ILADLC( LASTV, N, C, LDC ) |
| 392 |
* |
| 393 |
* W := C' * V' = (C1'*V1' + C2'*V2') (stored in WORK) |
| 394 |
* |
| 395 |
* W := C1' |
| 396 |
* |
| 397 |
DO 130 J = 1, K |
| 398 |
CALL DCOPY( LASTC, C( J, 1 ), LDC, WORK( 1, J ), 1 ) |
| 399 |
130 CONTINUE |
| 400 |
* |
| 401 |
* W := W * V1' |
| 402 |
* |
| 403 |
CALL DTRMM( 'Right', 'Upper', 'Transpose', 'Unit', |
| 404 |
$ LASTC, K, ONE, V, LDV, WORK, LDWORK ) |
| 405 |
IF( LASTV.GT.K ) THEN |
| 406 |
* |
| 407 |
* W := W + C2'*V2' |
| 408 |
* |
| 409 |
CALL DGEMM( 'Transpose', 'Transpose', |
| 410 |
$ LASTC, K, LASTV-K, |
| 411 |
$ ONE, C( K+1, 1 ), LDC, V( 1, K+1 ), LDV, |
| 412 |
$ ONE, WORK, LDWORK ) |
| 413 |
END IF |
| 414 |
* |
| 415 |
* W := W * T' or W * T |
| 416 |
* |
| 417 |
CALL DTRMM( 'Right', 'Upper', TRANST, 'Non-unit', |
| 418 |
$ LASTC, K, ONE, T, LDT, WORK, LDWORK ) |
| 419 |
* |
| 420 |
* C := C - V' * W' |
| 421 |
* |
| 422 |
IF( LASTV.GT.K ) THEN |
| 423 |
* |
| 424 |
* C2 := C2 - V2' * W' |
| 425 |
* |
| 426 |
CALL DGEMM( 'Transpose', 'Transpose', |
| 427 |
$ LASTV-K, LASTC, K, |
| 428 |
$ -ONE, V( 1, K+1 ), LDV, WORK, LDWORK, |
| 429 |
$ ONE, C( K+1, 1 ), LDC ) |
| 430 |
END IF |
| 431 |
* |
| 432 |
* W := W * V1 |
| 433 |
* |
| 434 |
CALL DTRMM( 'Right', 'Upper', 'No transpose', 'Unit', |
| 435 |
$ LASTC, K, ONE, V, LDV, WORK, LDWORK ) |
| 436 |
* |
| 437 |
* C1 := C1 - W' |
| 438 |
* |
| 439 |
DO 150 J = 1, K |
| 440 |
DO 140 I = 1, LASTC |
| 441 |
C( J, I ) = C( J, I ) - WORK( I, J ) |
| 442 |
140 CONTINUE |
| 443 |
150 CONTINUE |
| 444 |
* |
| 445 |
ELSE IF( LSAME( SIDE, 'R' ) ) THEN |
| 446 |
* |
| 447 |
* Form C * H or C * H' where C = ( C1 C2 ) |
| 448 |
* |
| 449 |
LASTV = MAX( K, ILADLC( K, N, V, LDV ) ) |
| 450 |
LASTC = ILADLR( M, LASTV, C, LDC ) |
| 451 |
* |
| 452 |
* W := C * V' = (C1*V1' + C2*V2') (stored in WORK) |
| 453 |
* |
| 454 |
* W := C1 |
| 455 |
* |
| 456 |
DO 160 J = 1, K |
| 457 |
CALL DCOPY( LASTC, C( 1, J ), 1, WORK( 1, J ), 1 ) |
| 458 |
160 CONTINUE |
| 459 |
* |
| 460 |
* W := W * V1' |
| 461 |
* |
| 462 |
CALL DTRMM( 'Right', 'Upper', 'Transpose', 'Unit', |
| 463 |
$ LASTC, K, ONE, V, LDV, WORK, LDWORK ) |
| 464 |
IF( LASTV.GT.K ) THEN |
| 465 |
* |
| 466 |
* W := W + C2 * V2' |
| 467 |
* |
| 468 |
CALL DGEMM( 'No transpose', 'Transpose', |
| 469 |
$ LASTC, K, LASTV-K, |
| 470 |
$ ONE, C( 1, K+1 ), LDC, V( 1, K+1 ), LDV, |
| 471 |
$ ONE, WORK, LDWORK ) |
| 472 |
END IF |
| 473 |
* |
| 474 |
* W := W * T or W * T' |
| 475 |
* |
| 476 |
CALL DTRMM( 'Right', 'Upper', TRANS, 'Non-unit', |
| 477 |
$ LASTC, K, ONE, T, LDT, WORK, LDWORK ) |
| 478 |
* |
| 479 |
* C := C - W * V |
| 480 |
* |
| 481 |
IF( LASTV.GT.K ) THEN |
| 482 |
* |
| 483 |
* C2 := C2 - W * V2 |
| 484 |
* |
| 485 |
CALL DGEMM( 'No transpose', 'No transpose', |
| 486 |
$ LASTC, LASTV-K, K, |
| 487 |
$ -ONE, WORK, LDWORK, V( 1, K+1 ), LDV, |
| 488 |
$ ONE, C( 1, K+1 ), LDC ) |
| 489 |
END IF |
| 490 |
* |
| 491 |
* W := W * V1 |
| 492 |
* |
| 493 |
CALL DTRMM( 'Right', 'Upper', 'No transpose', 'Unit', |
| 494 |
$ LASTC, K, ONE, V, LDV, WORK, LDWORK ) |
| 495 |
* |
| 496 |
* C1 := C1 - W |
| 497 |
* |
| 498 |
DO 180 J = 1, K |
| 499 |
DO 170 I = 1, LASTC |
| 500 |
C( I, J ) = C( I, J ) - WORK( I, J ) |
| 501 |
170 CONTINUE |
| 502 |
180 CONTINUE |
| 503 |
* |
| 504 |
END IF |
| 505 |
* |
| 506 |
ELSE |
| 507 |
* |
| 508 |
* Let V = ( V1 V2 ) (V2: last K columns) |
| 509 |
* where V2 is unit lower triangular. |
| 510 |
* |
| 511 |
IF( LSAME( SIDE, 'L' ) ) THEN |
| 512 |
* |
| 513 |
* Form H * C or H' * C where C = ( C1 ) |
| 514 |
* ( C2 ) |
| 515 |
* |
| 516 |
LASTV = MAX( K, ILADLC( K, M, V, LDV ) ) |
| 517 |
LASTC = ILADLC( LASTV, N, C, LDC ) |
| 518 |
* |
| 519 |
* W := C' * V' = (C1'*V1' + C2'*V2') (stored in WORK) |
| 520 |
* |
| 521 |
* W := C2' |
| 522 |
* |
| 523 |
DO 190 J = 1, K |
| 524 |
CALL DCOPY( LASTC, C( LASTV-K+J, 1 ), LDC, |
| 525 |
$ WORK( 1, J ), 1 ) |
| 526 |
190 CONTINUE |
| 527 |
* |
| 528 |
* W := W * V2' |
| 529 |
* |
| 530 |
CALL DTRMM( 'Right', 'Lower', 'Transpose', 'Unit', |
| 531 |
$ LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV, |
| 532 |
$ WORK, LDWORK ) |
| 533 |
IF( LASTV.GT.K ) THEN |
| 534 |
* |
| 535 |
* W := W + C1'*V1' |
| 536 |
* |
| 537 |
CALL DGEMM( 'Transpose', 'Transpose', |
| 538 |
$ LASTC, K, LASTV-K, ONE, C, LDC, V, LDV, |
| 539 |
$ ONE, WORK, LDWORK ) |
| 540 |
END IF |
| 541 |
* |
| 542 |
* W := W * T' or W * T |
| 543 |
* |
| 544 |
CALL DTRMM( 'Right', 'Lower', TRANST, 'Non-unit', |
| 545 |
$ LASTC, K, ONE, T, LDT, WORK, LDWORK ) |
| 546 |
* |
| 547 |
* C := C - V' * W' |
| 548 |
* |
| 549 |
IF( LASTV.GT.K ) THEN |
| 550 |
* |
| 551 |
* C1 := C1 - V1' * W' |
| 552 |
* |
| 553 |
CALL DGEMM( 'Transpose', 'Transpose', |
| 554 |
$ LASTV-K, LASTC, K, -ONE, V, LDV, WORK, LDWORK, |
| 555 |
$ ONE, C, LDC ) |
| 556 |
END IF |
| 557 |
* |
| 558 |
* W := W * V2 |
| 559 |
* |
| 560 |
CALL DTRMM( 'Right', 'Lower', 'No transpose', 'Unit', |
| 561 |
$ LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV, |
| 562 |
$ WORK, LDWORK ) |
| 563 |
* |
| 564 |
* C2 := C2 - W' |
| 565 |
* |
| 566 |
DO 210 J = 1, K |
| 567 |
DO 200 I = 1, LASTC |
| 568 |
C( LASTV-K+J, I ) = C( LASTV-K+J, I ) - WORK(I, J) |
| 569 |
200 CONTINUE |
| 570 |
210 CONTINUE |
| 571 |
* |
| 572 |
ELSE IF( LSAME( SIDE, 'R' ) ) THEN |
| 573 |
* |
| 574 |
* Form C * H or C * H' where C = ( C1 C2 ) |
| 575 |
* |
| 576 |
LASTV = MAX( K, ILADLC( K, N, V, LDV ) ) |
| 577 |
LASTC = ILADLR( M, LASTV, C, LDC ) |
| 578 |
* |
| 579 |
* W := C * V' = (C1*V1' + C2*V2') (stored in WORK) |
| 580 |
* |
| 581 |
* W := C2 |
| 582 |
* |
| 583 |
DO 220 J = 1, K |
| 584 |
CALL DCOPY( LASTC, C( 1, LASTV-K+J ), 1, |
| 585 |
$ WORK( 1, J ), 1 ) |
| 586 |
220 CONTINUE |
| 587 |
* |
| 588 |
* W := W * V2' |
| 589 |
* |
| 590 |
CALL DTRMM( 'Right', 'Lower', 'Transpose', 'Unit', |
| 591 |
$ LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV, |
| 592 |
$ WORK, LDWORK ) |
| 593 |
IF( LASTV.GT.K ) THEN |
| 594 |
* |
| 595 |
* W := W + C1 * V1' |
| 596 |
* |
| 597 |
CALL DGEMM( 'No transpose', 'Transpose', |
| 598 |
$ LASTC, K, LASTV-K, ONE, C, LDC, V, LDV, |
| 599 |
$ ONE, WORK, LDWORK ) |
| 600 |
END IF |
| 601 |
* |
| 602 |
* W := W * T or W * T' |
| 603 |
* |
| 604 |
CALL DTRMM( 'Right', 'Lower', TRANS, 'Non-unit', |
| 605 |
$ LASTC, K, ONE, T, LDT, WORK, LDWORK ) |
| 606 |
* |
| 607 |
* C := C - W * V |
| 608 |
* |
| 609 |
IF( LASTV.GT.K ) THEN |
| 610 |
* |
| 611 |
* C1 := C1 - W * V1 |
| 612 |
* |
| 613 |
CALL DGEMM( 'No transpose', 'No transpose', |
| 614 |
$ LASTC, LASTV-K, K, -ONE, WORK, LDWORK, V, LDV, |
| 615 |
$ ONE, C, LDC ) |
| 616 |
END IF |
| 617 |
* |
| 618 |
* W := W * V2 |
| 619 |
* |
| 620 |
CALL DTRMM( 'Right', 'Lower', 'No transpose', 'Unit', |
| 621 |
$ LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV, |
| 622 |
$ WORK, LDWORK ) |
| 623 |
* |
| 624 |
* C1 := C1 - W |
| 625 |
* |
| 626 |
DO 240 J = 1, K |
| 627 |
DO 230 I = 1, LASTC |
| 628 |
C( I, LASTV-K+J ) = C( I, LASTV-K+J ) - WORK(I, J) |
| 629 |
230 CONTINUE |
| 630 |
240 CONTINUE |
| 631 |
* |
| 632 |
END IF |
| 633 |
* |
| 634 |
END IF |
| 635 |
END IF |
| 636 |
* |
| 637 |
RETURN |
| 638 |
* |
| 639 |
* End of DLARFB |
| 640 |
* |
| 641 |
END |