SUBROUTINE PZLARF( SIDE, M, N, V, IV, JV, DESCV, INCV, TAU, $ C, IC, JC, DESCC, WORK ) * * -- ScaLAPACK auxiliary routine (version 1.5) -- * University of Tennessee, Knoxville, Oak Ridge National Laboratory, * and University of California, Berkeley. * May 1, 1997 * * .. Scalar Arguments .. CHARACTER SIDE INTEGER IC, INCV, IV, JC, JV, M, N * .. * .. Array Arguments .. INTEGER DESCC( * ), DESCV( * ) COMPLEX*16 C( * ), TAU( * ), V( * ), WORK( * ) * .. * * Purpose * ======= * * PZLARF applies a complex elementary reflector Q to a complex M-by-N * distributed matrix sub( C ) = C(IC:IC+M-1,JC:JC+N-1), from either the * left or the right. Q is represented in the form * * Q = I - tau * v * v' * * where tau is a complex scalar and v is a complex vector. * * If tau = 0, then Q is taken to be the unit matrix. * * Notes * ===== * * Each global data object is described by an associated description * vector. This vector stores the information required to establish * the mapping between an object element and its corresponding process * and memory location. * * Let A be a generic term for any 2D block cyclicly distributed array. * Such a global array has an associated description vector DESCA. * In the following comments, the character _ should be read as * "of the global array". * * NOTATION STORED IN EXPLANATION * --------------- -------------- -------------------------------------- * DTYPE_A(global) DESCA( DTYPE_ )The descriptor type. In this case, * DTYPE_A = 1. * CTXT_A (global) DESCA( CTXT_ ) The BLACS context handle, indicating * the BLACS process grid A is distribu- * ted over. The context itself is glo- * bal, but the handle (the integer * value) may vary. * M_A (global) DESCA( M_ ) The number of rows in the global * array A. * N_A (global) DESCA( N_ ) The number of columns in the global * array A. * MB_A (global) DESCA( MB_ ) The blocking factor used to distribute * the rows of the array. * NB_A (global) DESCA( NB_ ) The blocking factor used to distribute * the columns of the array. * RSRC_A (global) DESCA( RSRC_ ) The process row over which the first * row of the array A is distributed. * CSRC_A (global) DESCA( CSRC_ ) The process column over which the * first column of the array A is * distributed. * LLD_A (local) DESCA( LLD_ ) The leading dimension of the local * array. LLD_A >= MAX(1,LOCr(M_A)). * * Let K be the number of rows or columns of a distributed matrix, * and assume that its process grid has dimension p x q. * LOCr( K ) denotes the number of elements of K that a process * would receive if K were distributed over the p processes of its * process column. * Similarly, LOCc( K ) denotes the number of elements of K that a * process would receive if K were distributed over the q processes of * its process row. * The values of LOCr() and LOCc() may be determined via a call to the * ScaLAPACK tool function, NUMROC: * LOCr( M ) = NUMROC( M, MB_A, MYROW, RSRC_A, NPROW ), * LOCc( N ) = NUMROC( N, NB_A, MYCOL, CSRC_A, NPCOL ). * An upper bound for these quantities may be computed by: * LOCr( M ) <= ceil( ceil(M/MB_A)/NPROW )*MB_A * LOCc( N ) <= ceil( ceil(N/NB_A)/NPCOL )*NB_A * * Because vectors may be viewed as a subclass of matrices, a * distributed vector is considered to be a distributed matrix. * * Restrictions * ============ * * If SIDE = 'Left' and INCV = 1, then the row process having the first * entry V(IV,JV) must also have the first row of sub( C ). Moreover, * MOD(IV-1,MB_V) must be equal to MOD(IC-1,MB_C), if INCV=M_V, only * the last equality must be satisfied. * * If SIDE = 'Right' and INCV = M_V then the column process having the * first entry V(IV,JV) must also have the first column of sub( C ) and * MOD(JV-1,NB_V) must be equal to MOD(JC-1,NB_C), if INCV = 1 only the * last equality must be satisfied. * * Arguments * ========= * * SIDE (global input) CHARACTER * = 'L': form Q * sub( C ), * = 'R': form sub( C ) * Q. * * M (global input) INTEGER * The number of rows to be operated on i.e the number of rows * of the distributed submatrix sub( C ). M >= 0. * * N (global input) INTEGER * The number of columns to be operated on i.e the number of * columns of the distributed submatrix sub( C ). N >= 0. * * V (local input) COMPLEX*16 pointer into the local memory * to an array of dimension (LLD_V,*) containing the local * pieces of the distributed vectors V representing the * Householder transformation Q, * V(IV:IV+M-1,JV) if SIDE = 'L' and INCV = 1, * V(IV,JV:JV+M-1) if SIDE = 'L' and INCV = M_V, * V(IV:IV+N-1,JV) if SIDE = 'R' and INCV = 1, * V(IV,JV:JV+N-1) if SIDE = 'R' and INCV = M_V, * * The vector v in the representation of Q. V is not used if * TAU = 0. * * IV (global input) INTEGER * The row index in the global array V indicating the first * row of sub( V ). * * JV (global input) INTEGER * The column index in the global array V indicating the * first column of sub( V ). * * DESCV (global and local input) INTEGER array of dimension DLEN_. * The array descriptor for the distributed matrix V. * * INCV (global input) INTEGER * The global increment for the elements of V. Only two values * of INCV are supported in this version, namely 1 and M_V. * INCV must not be zero. * * TAU (local input) COMPLEX*16, array, dimension LOCc(JV) if * INCV = 1, and LOCr(IV) otherwise. This array contains the * Householder scalars related to the Householder vectors. * TAU is tied to the distributed matrix V. * * C (local input/local output) COMPLEX*16 pointer into the * local memory to an array of dimension (LLD_C, LOCc(JC+N-1) ), * containing the local pieces of sub( C ). On exit, sub( C ) * is overwritten by the Q * sub( C ) if SIDE = 'L', or * sub( C ) * Q if SIDE = 'R'. * * IC (global input) INTEGER * The row index in the global array C indicating the first * row of sub( C ). * * JC (global input) INTEGER * The column index in the global array C indicating the * first column of sub( C ). * * DESCC (global and local input) INTEGER array of dimension DLEN_. * The array descriptor for the distributed matrix C. * * WORK (local workspace) COMPLEX*16 array, dimension (LWORK) * If INCV = 1, * if SIDE = 'L', * if IVCOL = ICCOL, * LWORK >= NqC0 * else * LWORK >= MpC0 + MAX( 1, NqC0 ) * end if * else if SIDE = 'R', * LWORK >= NqC0 + MAX( MAX( 1, MpC0 ), NUMROC( NUMROC( * N+ICOFFC,NB_V,0,0,NPCOL ),NB_V,0,0,LCMQ ) ) * end if * else if INCV = M_V, * if SIDE = 'L', * LWORK >= MpC0 + MAX( MAX( 1, NqC0 ), NUMROC( NUMROC( * M+IROFFC,MB_V,0,0,NPROW ),MB_V,0,0,LCMP ) ) * else if SIDE = 'R', * if IVROW = ICROW, * LWORK >= MpC0 * else * LWORK >= NqC0 + MAX( 1, MpC0 ) * end if * end if * end if * * where LCM is the least common multiple of NPROW and NPCOL and * LCM = ILCM( NPROW, NPCOL ), LCMP = LCM / NPROW, * LCMQ = LCM / NPCOL, * * IROFFC = MOD( IC-1, MB_C ), ICOFFC = MOD( JC-1, NB_C ), * ICROW = INDXG2P( IC, MB_C, MYROW, RSRC_C, NPROW ), * ICCOL = INDXG2P( JC, NB_C, MYCOL, CSRC_C, NPCOL ), * MpC0 = NUMROC( M+IROFFC, MB_C, MYROW, ICROW, NPROW ), * NqC0 = NUMROC( N+ICOFFC, NB_C, MYCOL, ICCOL, NPCOL ), * * ILCM, INDXG2P and NUMROC are ScaLAPACK tool functions; * MYROW, MYCOL, NPROW and NPCOL can be determined by calling * the subroutine BLACS_GRIDINFO. * * Alignment requirements * ====================== * * The distributed submatrices V(IV:*, JV:*) and C(IC:IC+M-1,JC:JC+N-1) * must verify some alignment properties, namely the following * expressions should be true: * * MB_V = NB_V, * * If INCV = 1, * If SIDE = 'Left', * ( MB_V.EQ.MB_C .AND. IROFFV.EQ.IROFFC .AND. IVROW.EQ.ICROW ) * If SIDE = 'Right', * ( MB_V.EQ.NB_A .AND. MB_V.EQ.NB_C .AND. IROFFV.EQ.ICOFFC ) * else if INCV = M_V, * If SIDE = 'Left', * ( MB_V.EQ.NB_V .AND. MB_V.EQ.MB_C .AND. ICOFFV.EQ.IROFFC ) * If SIDE = 'Right', * ( NB_V.EQ.NB_C .AND. ICOFFV.EQ.ICOFFC .AND. IVCOL.EQ.ICCOL ) * end if * * ===================================================================== * * .. Parameters .. INTEGER BLOCK_CYCLIC_2D, CSRC_, CTXT_, DLEN_, DTYPE_, $ LLD_, MB_, M_, NB_, N_, RSRC_ PARAMETER ( BLOCK_CYCLIC_2D = 1, DLEN_ = 9, DTYPE_ = 1, $ CTXT_ = 2, M_ = 3, N_ = 4, MB_ = 5, NB_ = 6, $ RSRC_ = 7, CSRC_ = 8, LLD_ = 9 ) COMPLEX*16 ONE, ZERO PARAMETER ( ONE = ( 1.0D+0, 0.0D+0 ), $ ZERO = ( 0.0D+0, 0.0D+0 ) ) * .. * .. Local Scalars .. LOGICAL CCBLCK, CRBLCK CHARACTER COLBTOP, ROWBTOP INTEGER ICCOL, ICOFF, ICROW, ICTXT, IIC, IIV, IOFFC, $ IOFFV, IPW, IROFF, IVCOL, IVROW, JJC, JJV, LDC, $ LDV, MYCOL, MYROW, MP, NCC, NCV, NPCOL, NPROW, $ NQ, RDEST COMPLEX*16 TAULOC * .. * .. External Subroutines .. EXTERNAL BLACS_GRIDINFO, INFOG2L, PTOPGET, PBZTRNV, $ ZCOPY, ZGEBR2D, ZGEBS2D, ZGEMV, $ ZGERC, ZGERV2D, ZGESD2D, ZGSUM2D, $ ZLASET * .. * .. External Functions .. LOGICAL LSAME INTEGER NUMROC EXTERNAL LSAME, NUMROC * .. * .. Intrinsic Functions .. INTRINSIC MIN, MOD * .. * .. Executable Statements .. * * Quick return if possible * IF( M.LE.0 .OR. N.LE.0 ) $ RETURN * * Get grid parameters. * ICTXT = DESCC( CTXT_ ) CALL BLACS_GRIDINFO( ICTXT, NPROW, NPCOL, MYROW, MYCOL ) * * Figure local indexes * CALL INFOG2L( IC, JC, DESCC, NPROW, NPCOL, MYROW, MYCOL, IIC, JJC, $ ICROW, ICCOL ) CALL INFOG2L( IV, JV, DESCV, NPROW, NPCOL, MYROW, MYCOL, IIV, JJV, $ IVROW, IVCOL ) NCC = NUMROC( DESCC( N_ ), DESCC( NB_ ), MYCOL, DESCC( CSRC_ ), $ NPCOL ) NCV = NUMROC( DESCV( N_ ), DESCV( NB_ ), MYCOL, DESCV( CSRC_ ), $ NPCOL ) LDC = DESCC( LLD_ ) LDV = DESCV( LLD_ ) IIC = MIN( IIC, LDC ) IIV = MIN( IIV, LDV ) JJC = MIN( JJC, NCC ) JJV = MIN( JJV, NCV ) IOFFC = IIC+(JJC-1)*LDC IOFFV = IIV+(JJV-1)*LDV * IROFF = MOD( IC-1, DESCC( MB_ ) ) ICOFF = MOD( JC-1, DESCC( NB_ ) ) MP = NUMROC( M+IROFF, DESCC( MB_ ), MYROW, ICROW, NPROW ) NQ = NUMROC( N+ICOFF, DESCC( NB_ ), MYCOL, ICCOL, NPCOL ) IF( MYROW.EQ.ICROW ) $ MP = MP - IROFF IF( MYCOL.EQ.ICCOL ) $ NQ = NQ - ICOFF * * Is sub( C ) only distributed over a process row ? * CRBLCK = ( M.LE.(DESCC( MB_ )-IROFF) ) * * Is sub( C ) only distributed over a process column ? * CCBLCK = ( N.LE.(DESCC( NB_ )-ICOFF) ) * IF( LSAME( SIDE, 'L' ) ) THEN * IF( CRBLCK ) THEN RDEST = ICROW ELSE RDEST = -1 END IF * IF( CCBLCK ) THEN * * sub( C ) is distributed over a process column * IF( DESCV( M_ ).EQ.INCV ) THEN * * Transpose row vector V * IPW = MP+1 CALL PBZTRNV( ICTXT, 'Rowwise', 'Transpose', M, $ DESCV( NB_ ), IROFF, V( IOFFV ), LDV, ZERO, $ WORK, 1, IVROW, IVCOL, ICROW, ICCOL, $ WORK( IPW ) ) * * Perform the local computation within a process column * IF( MYCOL.EQ.ICCOL ) THEN * IF( MYROW.EQ.IVROW ) THEN * CALL ZGEBS2D( ICTXT, 'Columnwise', ' ', 1, 1, $ TAU( IIV ), 1 ) TAULOC = TAU( IIV ) * ELSE * CALL ZGEBR2D( ICTXT, 'Columnwise', ' ', 1, 1, $ TAULOC, 1, IVROW, MYCOL ) * END IF * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C )' * v * IF( MP.GT.0 ) THEN CALL ZGEMV( 'Conjugate transpose', MP, NQ, ONE, $ C( IOFFC ), LDC, WORK, 1, ZERO, $ WORK( IPW ), 1 ) ELSE CALL ZLASET( 'All', NQ, 1, ZERO, ZERO, $ WORK( IPW ), MAX( 1, NQ ) ) END IF CALL ZGSUM2D( ICTXT, 'Columnwise', ' ', NQ, 1, $ WORK( IPW ), MAX( 1, NQ ), RDEST, $ MYCOL ) * * sub( C ) := sub( C ) - v * w' * CALL ZGERC( MP, NQ, -TAULOC, WORK, 1, WORK( IPW ), $ 1, C( IOFFC ), LDC ) END IF * END IF * ELSE * * V is a column vector * IF( IVCOL.EQ.ICCOL ) THEN * * Perform the local computation within a process column * IF( MYCOL.EQ.ICCOL ) THEN * TAULOC = TAU( JJV ) * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C )' * v * IF( MP.GT.0 ) THEN CALL ZGEMV( 'Conjugate transpose', MP, NQ, $ ONE, C( IOFFC ), LDC, V( IOFFV ), 1, $ ZERO, WORK, 1 ) ELSE CALL ZLASET( 'All', NQ, 1, ZERO, ZERO, $ WORK, MAX( 1, NQ ) ) END IF CALL ZGSUM2D( ICTXT, 'Columnwise', ' ', NQ, 1, $ WORK, MAX( 1, NQ ), RDEST, MYCOL ) * * sub( C ) := sub( C ) - v * w' * CALL ZGERC( MP, NQ, -TAULOC, V( IOFFV ), 1, $ WORK, 1, C( IOFFC ), LDC ) END IF * END IF * ELSE * * Send V and TAU to the process column ICCOL * IF( MYCOL.EQ.IVCOL ) THEN * IPW = MP+1 CALL ZCOPY( MP, V( IOFFV ), 1, WORK, 1 ) WORK( IPW ) = TAU( JJV ) CALL ZGESD2D( ICTXT, IPW, 1, WORK, IPW, MYROW, $ ICCOL ) * ELSE IF( MYCOL.EQ.ICCOL ) THEN * IPW = MP+1 CALL ZGERV2D( ICTXT, IPW, 1, WORK, IPW, MYROW, $ IVCOL ) TAULOC = WORK( IPW ) * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C )' * v * IF( MP.GT.0 ) THEN CALL ZGEMV( 'Conjugate transpose', MP, NQ, $ ONE, C( IOFFC ), LDC, WORK, 1, $ ZERO, WORK( IPW ), 1 ) ELSE CALL ZLASET( 'All', NQ, 1, ZERO, ZERO, $ WORK( IPW ), MAX( 1, NQ ) ) END IF CALL ZGSUM2D( ICTXT, 'Columnwise', ' ', NQ, 1, $ WORK( IPW ), MAX( 1, NQ ), RDEST, $ MYCOL ) * * sub( C ) := sub( C ) - v * w' * CALL ZGERC( MP, NQ, -TAULOC, WORK, 1, $ WORK( IPW ), 1, C( IOFFC ), LDC ) END IF * END IF * END IF * END IF * ELSE * * sub( C ) is a proper distributed matrix * IF( DESCV( M_ ).EQ.INCV ) THEN * * Transpose and broadcast row vector V * IPW = MP+1 CALL PBZTRNV( ICTXT, 'Rowwise', 'Transpose', M, $ DESCV( NB_ ), IROFF, V( IOFFV ), LDV, ZERO, $ WORK, 1, IVROW, IVCOL, ICROW, -1, $ WORK( IPW ) ) * * Perform the local computation within a process column * IF( MYROW.EQ.IVROW ) THEN * CALL ZGEBS2D( ICTXT, 'Columnwise', ' ', 1, 1, $ TAU( IIV ), 1 ) TAULOC = TAU( IIV ) * ELSE * CALL ZGEBR2D( ICTXT, 'Columnwise', ' ', 1, 1, TAULOC, $ 1, IVROW, MYCOL ) * END IF * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C )' * v * IF( MP.GT.0 ) THEN CALL ZGEMV( 'Conjugate transpose', MP, NQ, ONE, $ C( IOFFC ), LDC, WORK, 1, ZERO, $ WORK( IPW ), 1 ) ELSE CALL ZLASET( 'All', NQ, 1, ZERO, ZERO, $ WORK( IPW ), MAX( 1, NQ ) ) END IF CALL ZGSUM2D( ICTXT, 'Columnwise', ' ', NQ, 1, $ WORK( IPW ), MAX( 1, NQ ), RDEST, $ MYCOL ) * * sub( C ) := sub( C ) - v * w' * CALL ZGERC( MP, NQ, -TAULOC, WORK, 1, WORK( IPW ), 1, $ C( IOFFC ), LDC ) END IF * ELSE * * Broadcast column vector V * CALL PTOPGET( ICTXT, 'Broadcast', 'Rowwise', ROWBTOP ) IF( MYCOL.EQ.IVCOL ) THEN * IPW = MP+1 CALL ZCOPY( MP, V( IOFFV ), 1, WORK, 1 ) WORK(IPW) = TAU( JJV ) CALL ZGEBS2D( ICTXT, 'Rowwise', ROWBTOP, IPW, 1, $ WORK, IPW ) TAULOC = TAU( JJV ) * ELSE * IPW = MP+1 CALL ZGEBR2D( ICTXT, 'Rowwise', ROWBTOP, IPW, 1, WORK, $ IPW, MYROW, IVCOL ) TAULOC = WORK( IPW ) * END IF * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C )' * v * IF( MP.GT.0 ) THEN CALL ZGEMV( 'Conjugate transpose', MP, NQ, ONE, $ C( IOFFC ), LDC, WORK, 1, ZERO, $ WORK( IPW ), 1 ) ELSE CALL ZLASET( 'All', NQ, 1, ZERO, ZERO, $ WORK( IPW ), MAX( 1, NQ ) ) END IF CALL ZGSUM2D( ICTXT, 'Columnwise', ' ', NQ, 1, $ WORK( IPW ), MAX( 1, NQ ), RDEST, $ MYCOL ) * * sub( C ) := sub( C ) - v * w' * CALL ZGERC( MP, NQ, -TAULOC, WORK, 1, WORK( IPW ), 1, $ C( IOFFC ), LDC ) END IF * END IF * END IF * ELSE * IF( CCBLCK ) THEN RDEST = MYROW ELSE RDEST = -1 END IF * IF( CRBLCK ) THEN * * sub( C ) is distributed over a process row * IF( DESCV( M_ ).EQ.INCV ) THEN * * V is a row vector * IF( IVROW.EQ.ICROW ) THEN * * Perform the local computation within a process row * IF( MYROW.EQ.ICROW ) THEN * TAULOC = TAU( IIV ) * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C ) * v * IF( NQ.GT.0 ) THEN CALL ZGEMV( 'No transpose', MP, NQ, ONE, $ C( IOFFC ), LDC, V( IOFFV ), LDV, $ ZERO, WORK, 1 ) ELSE CALL ZLASET( 'All', MP, 1, ZERO, ZERO, $ WORK, MAX( 1, MP ) ) END IF CALL ZGSUM2D( ICTXT, 'Rowwise', ' ', MP, 1, $ WORK, MAX( 1, MP ), RDEST, ICCOL ) * * sub( C ) := sub( C ) - w * v' * CALL ZGERC( MP, NQ, -TAULOC, WORK, 1, $ V( IOFFV ), LDV, C( IOFFC ), LDC ) END IF * END IF * ELSE * * Send V and TAU to the process row ICROW * IF( MYROW.EQ.IVROW ) THEN * IPW = NQ+1 CALL ZCOPY( NQ, V( IOFFV ), LDV, WORK, 1 ) WORK(IPW) = TAU( IIV ) CALL ZGESD2D( ICTXT, IPW, 1, WORK, IPW, ICROW, $ MYCOL ) * ELSE IF( MYROW.EQ.ICROW ) THEN * IPW = NQ+1 CALL ZGERV2D( ICTXT, IPW, 1, WORK, IPW, IVROW, $ MYCOL ) TAULOC = WORK( IPW ) * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C ) * v * IF( NQ.GT.0 ) THEN CALL ZGEMV( 'No transpose', MP, NQ, ONE, $ C( IOFFC ), LDC, WORK, 1, ZERO, $ WORK( IPW ), 1 ) ELSE CALL ZLASET( 'All', MP, 1, ZERO, ZERO, $ WORK( IPW ), MAX( 1, MP ) ) END IF CALL ZGSUM2D( ICTXT, 'Rowwise', ' ', MP, 1, $ WORK( IPW ), MAX( 1, MP ), RDEST, $ ICCOL ) * * sub( C ) := sub( C ) - w * v' * CALL ZGERC( MP, NQ, -TAULOC, WORK( IPW ), 1, $ WORK, 1, C( IOFFC ), LDC ) END IF * END IF * END IF * ELSE * * Transpose column vector V * IPW = NQ+1 CALL PBZTRNV( ICTXT, 'Columnwise', 'Transpose', N, $ DESCV( MB_ ), ICOFF, V( IOFFV ), 1, ZERO, $ WORK, 1, IVROW, IVCOL, ICROW, ICCOL, $ WORK( IPW ) ) * * Perform the local computation within a process column * IF( MYROW.EQ.ICROW ) THEN * IF( MYCOL.EQ.IVCOL ) THEN * CALL ZGEBS2D( ICTXT, 'Rowwise', ' ', 1, 1, $ TAU( JJV ), 1 ) TAULOC = TAU( JJV ) * ELSE * CALL ZGEBR2D( ICTXT, 'Rowwise', ' ', 1, 1, TAULOC, $ 1, MYROW, IVCOL ) * END IF * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C ) * v * IF( NQ.GT.0 ) THEN CALL ZGEMV( 'No transpose', MP, NQ, ONE, $ C( IOFFC ), LDC, WORK, 1, ZERO, $ WORK( IPW ), 1 ) ELSE CALL ZLASET( 'All', MP, 1, ZERO, ZERO, $ WORK( IPW ), MAX( 1, MP ) ) END IF CALL ZGSUM2D( ICTXT, 'Rowwise', ' ', MP, 1, $ WORK( IPW ), MAX( 1, MP ), RDEST, $ ICCOL ) * * sub( C ) := sub( C ) - w * v' * CALL ZGERC( MP, NQ, -TAULOC, WORK( IPW ), 1, WORK, $ 1, C( IOFFC ), LDC ) END IF * END IF * END IF * ELSE * * sub( C ) is a proper distributed matrix * IF( DESCV( M_ ).EQ.INCV ) THEN * * Broadcast row vector V * CALL PTOPGET( ICTXT, 'Broadcast', 'Columnwise', COLBTOP ) IF( MYROW.EQ.IVROW ) THEN * IPW = NQ+1 CALL ZCOPY( NQ, V( IOFFV ), LDV, WORK, 1 ) WORK(IPW) = TAU( IIV ) CALL ZGEBS2D( ICTXT, 'Columnwise', COLBTOP, IPW, 1, $ WORK, IPW ) TAULOC = TAU( IIV ) * ELSE * IPW = NQ+1 CALL ZGEBR2D( ICTXT, 'Columnwise', COLBTOP, IPW, 1, $ WORK, IPW, IVROW, MYCOL ) TAULOC = WORK( IPW ) * END IF * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C ) * v * IF( NQ.GT.0 ) THEN CALL ZGEMV( 'No Transpose', MP, NQ, ONE, $ C( IOFFC ), LDC, WORK, 1, ZERO, $ WORK( IPW ), 1 ) ELSE CALL ZLASET( 'All', MP, 1, ZERO, ZERO, $ WORK( IPW ), MAX( 1, MP ) ) END IF CALL ZGSUM2D( ICTXT, 'Rowwise', ' ', MP, 1, $ WORK( IPW ), MAX( 1, MP ), RDEST, $ ICCOL ) * * sub( C ) := sub( C ) - w * v' * CALL ZGERC( MP, NQ, -TAULOC, WORK( IPW ), 1, WORK, 1, $ C( IOFFC ), LDC ) END IF * ELSE * * Transpose and broadcast column vector V * IPW = NQ+1 CALL PBZTRNV( ICTXT, 'Columnwise', 'Transpose', N, $ DESCV( MB_ ), ICOFF, V( IOFFV ), 1, ZERO, $ WORK, 1, IVROW, IVCOL, -1, ICCOL, $ WORK( IPW ) ) * * Perform the local computation within a process column * IF( MYCOL.EQ.IVCOL ) THEN * CALL ZGEBS2D( ICTXT, 'Rowwise', ' ', 1, 1, TAU( JJV ), $ 1 ) TAULOC = TAU( JJV ) * ELSE * CALL ZGEBR2D( ICTXT, 'Rowwise', ' ', 1, 1, TAULOC, 1, $ MYROW, IVCOL ) * END IF * IF( TAULOC.NE.ZERO ) THEN * * w := sub( C ) * v * IF( NQ.GT.0 ) THEN CALL ZGEMV( 'No transpose', MP, NQ, ONE, $ C( IOFFC ), LDC, WORK, 1, ZERO, $ WORK( IPW ), 1 ) ELSE CALL ZLASET( 'All', MP, 1, ZERO, ZERO, WORK( IPW ), $ MAX( 1, MP ) ) END IF CALL ZGSUM2D( ICTXT, 'Rowwise', ' ', MP, 1, $ WORK( IPW ), MAX( 1, MP ), RDEST, $ ICCOL ) * * sub( C ) := sub( C ) - w * v' * CALL ZGERC( MP, NQ, -TAULOC, WORK( IPW ), 1, WORK, 1, $ C( IOFFC ), LDC ) END IF * END IF * END IF * END IF * RETURN * * End of PZLARF * END