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				| *> \brief \b CLARFB | |
| * | |
| *  =========== DOCUMENTATION =========== | |
| * | |
| * Online html documentation available at  | |
| *            http://www.netlib.org/lapack/explore-html/  | |
| * | |
| *> \htmlonly | |
| *> Download CLARFB + dependencies  | |
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.tgz?format=tgz&filename=/lapack/lapack_routine/clarfb.f">  | |
| *> [TGZ]</a>  | |
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.zip?format=zip&filename=/lapack/lapack_routine/clarfb.f">  | |
| *> [ZIP]</a>  | |
| *> <a href="http://www.netlib.org/cgi-bin/netlibfiles.txt?format=txt&filename=/lapack/lapack_routine/clarfb.f">  | |
| *> [TXT]</a> | |
| *> \endhtmlonly  | |
| * | |
| *  Definition: | |
| *  =========== | |
| * | |
| *       SUBROUTINE CLARFB( SIDE, TRANS, DIRECT, STOREV, M, N, K, V, LDV, | |
| *                          T, LDT, C, LDC, WORK, LDWORK ) | |
| *  | |
| *       .. Scalar Arguments .. | |
| *       CHARACTER          DIRECT, SIDE, STOREV, TRANS | |
| *       INTEGER            K, LDC, LDT, LDV, LDWORK, M, N | |
| *       .. | |
| *       .. Array Arguments .. | |
| *       COMPLEX            C( LDC, * ), T( LDT, * ), V( LDV, * ), | |
| *      $                   WORK( LDWORK, * ) | |
| *       .. | |
| *   | |
| * | |
| *> \par Purpose: | |
| *  ============= | |
| *> | |
| *> \verbatim | |
| *> | |
| *> CLARFB applies a complex block reflector H or its transpose H**H to a | |
| *> complex M-by-N matrix C, from either the left or the right. | |
| *> \endverbatim | |
| * | |
| *  Arguments: | |
| *  ========== | |
| * | |
| *> \param[in] SIDE | |
| *> \verbatim | |
| *>          SIDE is CHARACTER*1 | |
| *>          = 'L': apply H or H**H from the Left | |
| *>          = 'R': apply H or H**H from the Right | |
| *> \endverbatim | |
| *> | |
| *> \param[in] TRANS | |
| *> \verbatim | |
| *>          TRANS is CHARACTER*1 | |
| *>          = 'N': apply H (No transpose) | |
| *>          = 'C': apply H**H (Conjugate transpose) | |
| *> \endverbatim | |
| *> | |
| *> \param[in] DIRECT | |
| *> \verbatim | |
| *>          DIRECT is CHARACTER*1 | |
| *>          Indicates how H is formed from a product of elementary | |
| *>          reflectors | |
| *>          = 'F': H = H(1) H(2) . . . H(k) (Forward) | |
| *>          = 'B': H = H(k) . . . H(2) H(1) (Backward) | |
| *> \endverbatim | |
| *> | |
| *> \param[in] STOREV | |
| *> \verbatim | |
| *>          STOREV is CHARACTER*1 | |
| *>          Indicates how the vectors which define the elementary | |
| *>          reflectors are stored: | |
| *>          = 'C': Columnwise | |
| *>          = 'R': Rowwise | |
| *> \endverbatim | |
| *> | |
| *> \param[in] M | |
| *> \verbatim | |
| *>          M is INTEGER | |
| *>          The number of rows of the matrix C. | |
| *> \endverbatim | |
| *> | |
| *> \param[in] N | |
| *> \verbatim | |
| *>          N is INTEGER | |
| *>          The number of columns of the matrix C. | |
| *> \endverbatim | |
| *> | |
| *> \param[in] K | |
| *> \verbatim | |
| *>          K is INTEGER | |
| *>          The order of the matrix T (= the number of elementary | |
| *>          reflectors whose product defines the block reflector). | |
| *> \endverbatim | |
| *> | |
| *> \param[in] V | |
| *> \verbatim | |
| *>          V is COMPLEX array, dimension | |
| *>                                (LDV,K) if STOREV = 'C' | |
| *>                                (LDV,M) if STOREV = 'R' and SIDE = 'L' | |
| *>                                (LDV,N) if STOREV = 'R' and SIDE = 'R' | |
| *>          The matrix V. See Further Details. | |
| *> \endverbatim | |
| *> | |
| *> \param[in] LDV | |
| *> \verbatim | |
| *>          LDV is INTEGER | |
| *>          The leading dimension of the array V. | |
| *>          If STOREV = 'C' and SIDE = 'L', LDV >= max(1,M); | |
| *>          if STOREV = 'C' and SIDE = 'R', LDV >= max(1,N); | |
| *>          if STOREV = 'R', LDV >= K. | |
| *> \endverbatim | |
| *> | |
| *> \param[in] T | |
| *> \verbatim | |
| *>          T is COMPLEX array, dimension (LDT,K) | |
| *>          The triangular K-by-K matrix T in the representation of the | |
| *>          block reflector. | |
| *> \endverbatim | |
| *> | |
| *> \param[in] LDT | |
| *> \verbatim | |
| *>          LDT is INTEGER | |
| *>          The leading dimension of the array T. LDT >= K. | |
| *> \endverbatim | |
| *> | |
| *> \param[in,out] C | |
| *> \verbatim | |
| *>          C is COMPLEX array, dimension (LDC,N) | |
| *>          On entry, the M-by-N matrix C. | |
| *>          On exit, C is overwritten by H*C or H**H*C or C*H or C*H**H. | |
| *> \endverbatim | |
| *> | |
| *> \param[in] LDC | |
| *> \verbatim | |
| *>          LDC is INTEGER | |
| *>          The leading dimension of the array C. LDC >= max(1,M). | |
| *> \endverbatim | |
| *> | |
| *> \param[out] WORK | |
| *> \verbatim | |
| *>          WORK is COMPLEX array, dimension (LDWORK,K) | |
| *> \endverbatim | |
| *> | |
| *> \param[in] LDWORK | |
| *> \verbatim | |
| *>          LDWORK is INTEGER | |
| *>          The leading dimension of the array WORK. | |
| *>          If SIDE = 'L', LDWORK >= max(1,N); | |
| *>          if SIDE = 'R', LDWORK >= max(1,M). | |
| *> \endverbatim | |
| * | |
| *  Authors: | |
| *  ======== | |
| * | |
| *> \author Univ. of Tennessee  | |
| *> \author Univ. of California Berkeley  | |
| *> \author Univ. of Colorado Denver  | |
| *> \author NAG Ltd.  | |
| * | |
| *> \date November 2011 | |
| * | |
| *> \ingroup complexOTHERauxiliary | |
| * | |
| *> \par Further Details: | |
| *  ===================== | |
| *> | |
| *> \verbatim | |
| *> | |
| *>  The shape of the matrix V and the storage of the vectors which define | |
| *>  the H(i) is best illustrated by the following example with n = 5 and | |
| *>  k = 3. The elements equal to 1 are not stored; the corresponding | |
| *>  array elements are modified but restored on exit. The rest of the | |
| *>  array is not used. | |
| *> | |
| *>  DIRECT = 'F' and STOREV = 'C':         DIRECT = 'F' and STOREV = 'R': | |
| *> | |
| *>               V = (  1       )                 V = (  1 v1 v1 v1 v1 ) | |
| *>                   ( v1  1    )                     (     1 v2 v2 v2 ) | |
| *>                   ( v1 v2  1 )                     (        1 v3 v3 ) | |
| *>                   ( v1 v2 v3 ) | |
| *>                   ( v1 v2 v3 ) | |
| *> | |
| *>  DIRECT = 'B' and STOREV = 'C':         DIRECT = 'B' and STOREV = 'R': | |
| *> | |
| *>               V = ( v1 v2 v3 )                 V = ( v1 v1  1       ) | |
| *>                   ( v1 v2 v3 )                     ( v2 v2 v2  1    ) | |
| *>                   (  1 v2 v3 )                     ( v3 v3 v3 v3  1 ) | |
| *>                   (     1 v3 ) | |
| *>                   (        1 ) | |
| *> \endverbatim | |
| *> | |
| *  ===================================================================== | |
|       SUBROUTINE CLARFB( SIDE, TRANS, DIRECT, STOREV, M, N, K, V, LDV, | |
|      $                   T, LDT, C, LDC, WORK, LDWORK ) | |
| * | |
| *  -- LAPACK auxiliary routine (version 3.4.0) -- | |
| *  -- LAPACK is a software package provided by Univ. of Tennessee,    -- | |
| *  -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- | |
| *     November 2011 | |
| * | |
| *     .. Scalar Arguments .. | |
|       CHARACTER          DIRECT, SIDE, STOREV, TRANS | |
|       INTEGER            K, LDC, LDT, LDV, LDWORK, M, N | |
| *     .. | |
| *     .. Array Arguments .. | |
|       COMPLEX            C( LDC, * ), T( LDT, * ), V( LDV, * ), | |
|      $                   WORK( LDWORK, * ) | |
| *     .. | |
| * | |
| *  ===================================================================== | |
| * | |
| *     .. Parameters .. | |
|       COMPLEX            ONE | |
|       PARAMETER          ( ONE = ( 1.0E+0, 0.0E+0 ) ) | |
| *     .. | |
| *     .. Local Scalars .. | |
|       CHARACTER          TRANST | |
|       INTEGER            I, J, LASTV, LASTC | |
| *     .. | |
| *     .. External Functions .. | |
|       LOGICAL            LSAME | |
|       INTEGER            ILACLR, ILACLC | |
|       EXTERNAL           LSAME, ILACLR, ILACLC | |
| *     .. | |
| *     .. External Subroutines .. | |
|       EXTERNAL           CCOPY, CGEMM, CLACGV, CTRMM | |
| *     .. | |
| *     .. Intrinsic Functions .. | |
|       INTRINSIC          CONJG | |
| *     .. | |
| *     .. Executable Statements .. | |
| * | |
| *     Quick return if possible | |
| * | |
|       IF( M.LE.0 .OR. N.LE.0 ) | |
|      $   RETURN | |
| * | |
|       IF( LSAME( TRANS, 'N' ) ) THEN | |
|          TRANST = 'C' | |
|       ELSE | |
|          TRANST = 'N' | |
|       END IF | |
| * | |
|       IF( LSAME( STOREV, 'C' ) ) THEN | |
| * | |
|          IF( LSAME( DIRECT, 'F' ) ) THEN | |
| * | |
| *           Let  V =  ( V1 )    (first K rows) | |
| *                     ( V2 ) | |
| *           where  V1  is unit lower triangular. | |
| * | |
|             IF( LSAME( SIDE, 'L' ) ) THEN | |
| * | |
| *              Form  H * C  or  H**H * C  where  C = ( C1 ) | |
| *                                                    ( C2 ) | |
| * | |
|                LASTV = MAX( K, ILACLR( M, K, V, LDV ) ) | |
|                LASTC = ILACLC( LASTV, N, C, LDC ) | |
| * | |
| *              W := C**H * V  =  (C1**H * V1 + C2**H * V2)  (stored in WORK) | |
| * | |
| *              W := C1**H | |
| * | |
|                DO 10 J = 1, K | |
|                   CALL CCOPY( LASTC, C( J, 1 ), LDC, WORK( 1, J ), 1 ) | |
|                   CALL CLACGV( LASTC, WORK( 1, J ), 1 ) | |
|    10          CONTINUE | |
| * | |
| *              W := W * V1 | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', 'No transpose', 'Unit', | |
|      $              LASTC, K, ONE, V, LDV, WORK, LDWORK ) | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 W := W + C2**H *V2 | |
| * | |
|                   CALL CGEMM( 'Conjugate transpose', 'No transpose', | |
|      $                 LASTC, K, LASTV-K, ONE, C( K+1, 1 ), LDC, | |
|      $                 V( K+1, 1 ), LDV, ONE, WORK, LDWORK ) | |
|                END IF | |
| * | |
| *              W := W * T**H  or  W * T | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', TRANST, 'Non-unit', | |
|      $              LASTC, K, ONE, T, LDT, WORK, LDWORK ) | |
| * | |
| *              C := C - V * W**H | |
| * | |
|                IF( M.GT.K ) THEN | |
| * | |
| *                 C2 := C2 - V2 * W**H | |
| * | |
|                   CALL CGEMM( 'No transpose', 'Conjugate transpose', | |
|      $                 LASTV-K, LASTC, K, -ONE, V( K+1, 1 ), LDV, | |
|      $                 WORK, LDWORK, ONE, C( K+1, 1 ), LDC ) | |
|                END IF | |
| * | |
| *              W := W * V1**H | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', 'Conjugate transpose', | |
|      $              'Unit', LASTC, K, ONE, V, LDV, WORK, LDWORK ) | |
| * | |
| *              C1 := C1 - W**H | |
| * | |
|                DO 30 J = 1, K | |
|                   DO 20 I = 1, LASTC | |
|                      C( J, I ) = C( J, I ) - CONJG( WORK( I, J ) ) | |
|    20             CONTINUE | |
|    30          CONTINUE | |
| * | |
|             ELSE IF( LSAME( SIDE, 'R' ) ) THEN | |
| * | |
| *              Form  C * H  or  C * H**H  where  C = ( C1  C2 ) | |
| * | |
|                LASTV = MAX( K, ILACLR( N, K, V, LDV ) ) | |
|                LASTC = ILACLR( M, LASTV, C, LDC ) | |
| * | |
| *              W := C * V  =  (C1*V1 + C2*V2)  (stored in WORK) | |
| * | |
| *              W := C1 | |
| * | |
|                DO 40 J = 1, K | |
|                   CALL CCOPY( LASTC, C( 1, J ), 1, WORK( 1, J ), 1 ) | |
|    40          CONTINUE | |
| * | |
| *              W := W * V1 | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', 'No transpose', 'Unit', | |
|      $              LASTC, K, ONE, V, LDV, WORK, LDWORK ) | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 W := W + C2 * V2 | |
| * | |
|                   CALL CGEMM( 'No transpose', 'No transpose', | |
|      $                 LASTC, K, LASTV-K, | |
|      $                 ONE, C( 1, K+1 ), LDC, V( K+1, 1 ), LDV, | |
|      $                 ONE, WORK, LDWORK ) | |
|                END IF | |
| * | |
| *              W := W * T  or  W * T**H | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', TRANS, 'Non-unit', | |
|      $              LASTC, K, ONE, T, LDT, WORK, LDWORK ) | |
| * | |
| *              C := C - W * V**H | |
| * | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 C2 := C2 - W * V2**H | |
| * | |
|                   CALL CGEMM( 'No transpose', 'Conjugate transpose', | |
|      $                 LASTC, LASTV-K, K, | |
|      $                 -ONE, WORK, LDWORK, V( K+1, 1 ), LDV, | |
|      $                 ONE, C( 1, K+1 ), LDC ) | |
|                END IF | |
| * | |
| *              W := W * V1**H | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', 'Conjugate transpose', | |
|      $              'Unit', LASTC, K, ONE, V, LDV, WORK, LDWORK ) | |
| * | |
| *              C1 := C1 - W | |
| * | |
|                DO 60 J = 1, K | |
|                   DO 50 I = 1, LASTC | |
|                      C( I, J ) = C( I, J ) - WORK( I, J ) | |
|    50             CONTINUE | |
|    60          CONTINUE | |
|             END IF | |
| * | |
|          ELSE | |
| * | |
| *           Let  V =  ( V1 ) | |
| *                     ( V2 )    (last K rows) | |
| *           where  V2  is unit upper triangular. | |
| * | |
|             IF( LSAME( SIDE, 'L' ) ) THEN | |
| * | |
| *              Form  H * C  or  H**H * C  where  C = ( C1 ) | |
| *                                                    ( C2 ) | |
| * | |
|                LASTV = MAX( K, ILACLR( M, K, V, LDV ) ) | |
|                LASTC = ILACLC( LASTV, N, C, LDC ) | |
| * | |
| *              W := C**H * V  =  (C1**H * V1 + C2**H * V2)  (stored in WORK) | |
| * | |
| *              W := C2**H | |
| * | |
|                DO 70 J = 1, K | |
|                   CALL CCOPY( LASTC, C( LASTV-K+J, 1 ), LDC, | |
|      $                 WORK( 1, J ), 1 ) | |
|                   CALL CLACGV( LASTC, WORK( 1, J ), 1 ) | |
|    70          CONTINUE | |
| * | |
| *              W := W * V2 | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', 'No transpose', 'Unit', | |
|      $              LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV, | |
|      $              WORK, LDWORK ) | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 W := W + C1**H*V1 | |
| * | |
|                   CALL CGEMM( 'Conjugate transpose', 'No transpose', | |
|      $                 LASTC, K, LASTV-K, ONE, C, LDC, V, LDV, | |
|      $                 ONE, WORK, LDWORK ) | |
|                END IF | |
| * | |
| *              W := W * T**H  or  W * T | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', TRANST, 'Non-unit', | |
|      $              LASTC, K, ONE, T, LDT, WORK, LDWORK ) | |
| * | |
| *              C := C - V * W**H | |
| * | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 C1 := C1 - V1 * W**H | |
| * | |
|                   CALL CGEMM( 'No transpose', 'Conjugate transpose', | |
|      $                 LASTV-K, LASTC, K, -ONE, V, LDV, WORK, LDWORK, | |
|      $                 ONE, C, LDC ) | |
|                END IF | |
| * | |
| *              W := W * V2**H | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', 'Conjugate transpose', | |
|      $              'Unit', LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV, | |
|      $              WORK, LDWORK ) | |
| * | |
| *              C2 := C2 - W**H | |
| * | |
|                DO 90 J = 1, K | |
|                   DO 80 I = 1, LASTC | |
|                      C( LASTV-K+J, I ) = C( LASTV-K+J, I ) - | |
|      $                               CONJG( WORK( I, J ) ) | |
|    80             CONTINUE | |
|    90          CONTINUE | |
| * | |
|             ELSE IF( LSAME( SIDE, 'R' ) ) THEN | |
| * | |
| *              Form  C * H  or  C * H**H  where  C = ( C1  C2 ) | |
| * | |
|                LASTV = MAX( K, ILACLR( N, K, V, LDV ) ) | |
|                LASTC = ILACLR( M, LASTV, C, LDC ) | |
| * | |
| *              W := C * V  =  (C1*V1 + C2*V2)  (stored in WORK) | |
| * | |
| *              W := C2 | |
| * | |
|                DO 100 J = 1, K | |
|                   CALL CCOPY( LASTC, C( 1, LASTV-K+J ), 1, | |
|      $                 WORK( 1, J ), 1 ) | |
|   100          CONTINUE | |
| * | |
| *              W := W * V2 | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', 'No transpose', 'Unit', | |
|      $              LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV, | |
|      $              WORK, LDWORK ) | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 W := W + C1 * V1 | |
| * | |
|                   CALL CGEMM( 'No transpose', 'No transpose', | |
|      $                 LASTC, K, LASTV-K, | |
|      $                 ONE, C, LDC, V, LDV, ONE, WORK, LDWORK ) | |
|                END IF | |
| * | |
| *              W := W * T  or  W * T**H | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', TRANS, 'Non-unit', | |
|      $              LASTC, K, ONE, T, LDT, WORK, LDWORK ) | |
| * | |
| *              C := C - W * V**H | |
| * | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 C1 := C1 - W * V1**H | |
| * | |
|                   CALL CGEMM( 'No transpose', 'Conjugate transpose', | |
|      $                 LASTC, LASTV-K, K, -ONE, WORK, LDWORK, V, LDV, | |
|      $                 ONE, C, LDC ) | |
|                END IF | |
| * | |
| *              W := W * V2**H | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', 'Conjugate transpose', | |
|      $              'Unit', LASTC, K, ONE, V( LASTV-K+1, 1 ), LDV, | |
|      $              WORK, LDWORK ) | |
| * | |
| *              C2 := C2 - W | |
| * | |
|                DO 120 J = 1, K | |
|                   DO 110 I = 1, LASTC | |
|                      C( I, LASTV-K+J ) = C( I, LASTV-K+J ) | |
|      $                    - WORK( I, J ) | |
|   110             CONTINUE | |
|   120          CONTINUE | |
|             END IF | |
|          END IF | |
| * | |
|       ELSE IF( LSAME( STOREV, 'R' ) ) THEN | |
| * | |
|          IF( LSAME( DIRECT, 'F' ) ) THEN | |
| * | |
| *           Let  V =  ( V1  V2 )    (V1: first K columns) | |
| *           where  V1  is unit upper triangular. | |
| * | |
|             IF( LSAME( SIDE, 'L' ) ) THEN | |
| * | |
| *              Form  H * C  or  H**H * C  where  C = ( C1 ) | |
| *                                                    ( C2 ) | |
| * | |
|                LASTV = MAX( K, ILACLC( K, M, V, LDV ) ) | |
|                LASTC = ILACLC( LASTV, N, C, LDC ) | |
| * | |
| *              W := C**H * V**H  =  (C1**H * V1**H + C2**H * V2**H) (stored in WORK) | |
| * | |
| *              W := C1**H | |
| * | |
|                DO 130 J = 1, K | |
|                   CALL CCOPY( LASTC, C( J, 1 ), LDC, WORK( 1, J ), 1 ) | |
|                   CALL CLACGV( LASTC, WORK( 1, J ), 1 ) | |
|   130          CONTINUE | |
| * | |
| *              W := W * V1**H | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', 'Conjugate transpose', | |
|      $                     'Unit', LASTC, K, ONE, V, LDV, WORK, LDWORK ) | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 W := W + C2**H*V2**H | |
| * | |
|                   CALL CGEMM( 'Conjugate transpose', | |
|      $                 'Conjugate transpose', LASTC, K, LASTV-K, | |
|      $                 ONE, C( K+1, 1 ), LDC, V( 1, K+1 ), LDV, | |
|      $                 ONE, WORK, LDWORK ) | |
|                END IF | |
| * | |
| *              W := W * T**H  or  W * T | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', TRANST, 'Non-unit', | |
|      $              LASTC, K, ONE, T, LDT, WORK, LDWORK ) | |
| * | |
| *              C := C - V**H * W**H | |
| * | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 C2 := C2 - V2**H * W**H | |
| * | |
|                   CALL CGEMM( 'Conjugate transpose', | |
|      $                 'Conjugate transpose', LASTV-K, LASTC, K, | |
|      $                 -ONE, V( 1, K+1 ), LDV, WORK, LDWORK, | |
|      $                 ONE, C( K+1, 1 ), LDC ) | |
|                END IF | |
| * | |
| *              W := W * V1 | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', 'No transpose', 'Unit', | |
|      $              LASTC, K, ONE, V, LDV, WORK, LDWORK ) | |
| * | |
| *              C1 := C1 - W**H | |
| * | |
|                DO 150 J = 1, K | |
|                   DO 140 I = 1, LASTC | |
|                      C( J, I ) = C( J, I ) - CONJG( WORK( I, J ) ) | |
|   140             CONTINUE | |
|   150          CONTINUE | |
| * | |
|             ELSE IF( LSAME( SIDE, 'R' ) ) THEN | |
| * | |
| *              Form  C * H  or  C * H**H  where  C = ( C1  C2 ) | |
| * | |
|                LASTV = MAX( K, ILACLC( K, N, V, LDV ) ) | |
|                LASTC = ILACLR( M, LASTV, C, LDC ) | |
| * | |
| *              W := C * V**H  =  (C1*V1**H + C2*V2**H)  (stored in WORK) | |
| * | |
| *              W := C1 | |
| * | |
|                DO 160 J = 1, K | |
|                   CALL CCOPY( LASTC, C( 1, J ), 1, WORK( 1, J ), 1 ) | |
|   160          CONTINUE | |
| * | |
| *              W := W * V1**H | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', 'Conjugate transpose', | |
|      $                     'Unit', LASTC, K, ONE, V, LDV, WORK, LDWORK ) | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 W := W + C2 * V2**H | |
| * | |
|                   CALL CGEMM( 'No transpose', 'Conjugate transpose', | |
|      $                 LASTC, K, LASTV-K, ONE, C( 1, K+1 ), LDC, | |
|      $                 V( 1, K+1 ), LDV, ONE, WORK, LDWORK ) | |
|                END IF | |
| * | |
| *              W := W * T  or  W * T**H | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', TRANS, 'Non-unit', | |
|      $              LASTC, K, ONE, T, LDT, WORK, LDWORK ) | |
| * | |
| *              C := C - W * V | |
| * | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 C2 := C2 - W * V2 | |
| * | |
|                   CALL CGEMM( 'No transpose', 'No transpose', | |
|      $                 LASTC, LASTV-K, K, | |
|      $                 -ONE, WORK, LDWORK, V( 1, K+1 ), LDV, | |
|      $                 ONE, C( 1, K+1 ), LDC ) | |
|                END IF | |
| * | |
| *              W := W * V1 | |
| * | |
|                CALL CTRMM( 'Right', 'Upper', 'No transpose', 'Unit', | |
|      $              LASTC, K, ONE, V, LDV, WORK, LDWORK ) | |
| * | |
| *              C1 := C1 - W | |
| * | |
|                DO 180 J = 1, K | |
|                   DO 170 I = 1, LASTC | |
|                      C( I, J ) = C( I, J ) - WORK( I, J ) | |
|   170             CONTINUE | |
|   180          CONTINUE | |
| * | |
|             END IF | |
| * | |
|          ELSE | |
| * | |
| *           Let  V =  ( V1  V2 )    (V2: last K columns) | |
| *           where  V2  is unit lower triangular. | |
| * | |
|             IF( LSAME( SIDE, 'L' ) ) THEN | |
| * | |
| *              Form  H * C  or  H**H * C  where  C = ( C1 ) | |
| *                                                    ( C2 ) | |
| * | |
|                LASTV = MAX( K, ILACLC( K, M, V, LDV ) ) | |
|                LASTC = ILACLC( LASTV, N, C, LDC ) | |
| * | |
| *              W := C**H * V**H  =  (C1**H * V1**H + C2**H * V2**H) (stored in WORK) | |
| * | |
| *              W := C2**H | |
| * | |
|                DO 190 J = 1, K | |
|                   CALL CCOPY( LASTC, C( LASTV-K+J, 1 ), LDC, | |
|      $                 WORK( 1, J ), 1 ) | |
|                   CALL CLACGV( LASTC, WORK( 1, J ), 1 ) | |
|   190          CONTINUE | |
| * | |
| *              W := W * V2**H | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', 'Conjugate transpose', | |
|      $              'Unit', LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV, | |
|      $              WORK, LDWORK ) | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 W := W + C1**H * V1**H | |
| * | |
|                   CALL CGEMM( 'Conjugate transpose', | |
|      $                 'Conjugate transpose', LASTC, K, LASTV-K, | |
|      $                 ONE, C, LDC, V, LDV, ONE, WORK, LDWORK ) | |
|                END IF | |
| * | |
| *              W := W * T**H  or  W * T | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', TRANST, 'Non-unit', | |
|      $              LASTC, K, ONE, T, LDT, WORK, LDWORK ) | |
| * | |
| *              C := C - V**H * W**H | |
| * | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 C1 := C1 - V1**H * W**H | |
| * | |
|                   CALL CGEMM( 'Conjugate transpose', | |
|      $                 'Conjugate transpose', LASTV-K, LASTC, K, | |
|      $                 -ONE, V, LDV, WORK, LDWORK, ONE, C, LDC ) | |
|                END IF | |
| * | |
| *              W := W * V2 | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', 'No transpose', 'Unit', | |
|      $              LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV, | |
|      $              WORK, LDWORK ) | |
| * | |
| *              C2 := C2 - W**H | |
| * | |
|                DO 210 J = 1, K | |
|                   DO 200 I = 1, LASTC | |
|                      C( LASTV-K+J, I ) = C( LASTV-K+J, I ) - | |
|      $                               CONJG( WORK( I, J ) ) | |
|   200             CONTINUE | |
|   210          CONTINUE | |
| * | |
|             ELSE IF( LSAME( SIDE, 'R' ) ) THEN | |
| * | |
| *              Form  C * H  or  C * H**H  where  C = ( C1  C2 ) | |
| * | |
|                LASTV = MAX( K, ILACLC( K, N, V, LDV ) ) | |
|                LASTC = ILACLR( M, LASTV, C, LDC ) | |
| * | |
| *              W := C * V**H  =  (C1*V1**H + C2*V2**H)  (stored in WORK) | |
| * | |
| *              W := C2 | |
| * | |
|                DO 220 J = 1, K | |
|                   CALL CCOPY( LASTC, C( 1, LASTV-K+J ), 1, | |
|      $                 WORK( 1, J ), 1 ) | |
|   220          CONTINUE | |
| * | |
| *              W := W * V2**H | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', 'Conjugate transpose', | |
|      $              'Unit', LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV, | |
|      $              WORK, LDWORK ) | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 W := W + C1 * V1**H | |
| * | |
|                   CALL CGEMM( 'No transpose', 'Conjugate transpose', | |
|      $                 LASTC, K, LASTV-K, ONE, C, LDC, V, LDV, ONE, | |
|      $                 WORK, LDWORK ) | |
|                END IF | |
| * | |
| *              W := W * T  or  W * T**H | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', TRANS, 'Non-unit', | |
|      $              LASTC, K, ONE, T, LDT, WORK, LDWORK ) | |
| * | |
| *              C := C - W * V | |
| * | |
|                IF( LASTV.GT.K ) THEN | |
| * | |
| *                 C1 := C1 - W * V1 | |
| * | |
|                   CALL CGEMM( 'No transpose', 'No transpose', | |
|      $                 LASTC, LASTV-K, K, -ONE, WORK, LDWORK, V, LDV, | |
|      $                 ONE, C, LDC ) | |
|                END IF | |
| * | |
| *              W := W * V2 | |
| * | |
|                CALL CTRMM( 'Right', 'Lower', 'No transpose', 'Unit', | |
|      $              LASTC, K, ONE, V( 1, LASTV-K+1 ), LDV, | |
|      $              WORK, LDWORK ) | |
| * | |
| *              C1 := C1 - W | |
| * | |
|                DO 240 J = 1, K | |
|                   DO 230 I = 1, LASTC | |
|                      C( I, LASTV-K+J ) = C( I, LASTV-K+J ) | |
|      $                    - WORK( I, J ) | |
|   230             CONTINUE | |
|   240          CONTINUE | |
| * | |
|             END IF | |
| * | |
|          END IF | |
|       END IF | |
| * | |
|       RETURN | |
| * | |
| *     End of CLARFB | |
| * | |
|       END
 |