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ScaLAPACK
2.0.2
ScaLAPACK: Scalable Linear Algebra PACKage
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ScaLAPACK
2.0.2
ScaLAPACK: Scalable Linear Algebra PACKage
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#include "../pblas.h"#include "../PBpblas.h"#include "../PBtools.h"#include "../PBblacs.h"#include "../PBblas.h"Go to the source code of this file.
Functions/Subroutines | |
| void | PB_CargFtoC (int IF, int JF, int *DESCIN, int *IC, int *JC, int *DESCOUT) |
| void PB_CargFtoC | ( | int | IF, |
| int | JF, | ||
| int * | DESCIN, | ||
| int * | IC, | ||
| int * | JC, | ||
| int * | DESCOUT | ||
| ) |
Definition at line 23 of file PB_CargFtoC.c.
{
/*
* Purpose
* =======
*
* PB_CargFtoC converts a descriptor DESCIN of type BLOCK_CYCLIC_2D
* or BLOCK_CYCLIC_INB_2D into a descriptor DESCOUT of type
* BLOCK_CYCLIC_INB_2D.
*
* Notes
* =====
*
* A description vector is associated with each 2D block-cyclicly dis-
* tributed matrix. This vector stores the information required to
* establish the mapping between a matrix entry and its corresponding
* process and memory location.
*
* In the following comments, the character _ should be read as
* "of the distributed matrix". Let A be a generic term for any 2D
* block cyclicly distributed matrix. Its description vector is DESCA:
*
* NOTATION STORED IN EXPLANATION
* ---------------- --------------- -----------------------------------
* DTYPE_A (global) DESCA( DTYPE1_ ) The descriptor type.
* CTXT_A (global) DESCA( CTXT1_ ) The BLACS context handle indicating
* the NPROW x NPCOL BLACS process
* grid A is distributed over. The
* context itself is global, but the
* handle (the integer value) may
* vary.
* M_A (global) DESCA( M1_ ) The number of rows in the distri-
* buted matrix A, M_A >= 0.
* N_A (global) DESCA( N1_ ) The number of columns in the dis-
* tributed matrix A, N_A >= 0.
* MB_A (global) DESCA( MB1_ ) The blocking factor used to distri-
* bute the rows of A, MB_A > 0.
* NB_A (global) DESCA( NB1_ ) The blocking factor used to distri-
* bute the columns of A, NB_A > 0.
* RSRC_A (global) DESCA( RSRC1_ ) The process row over which the
* first row of the matrix A is dis-
* tributed, NPROW > RSRC_A >= 0.
* CSRC_A (global) DESCA( CSRC1_ ) The process column over which the
* first column of A is distributed.
* NPCOL > CSRC_A >= 0.
* LLD_A (local) DESCA( LLD1_ ) The leading dimension of the local
* array storing the local blocks of
* the distributed matrix A,
* IF( Lc( 1, N_A ) > 0 )
* LLD_A >= MAX( 1, Lr( 1, M_A ) )
* ELSE
* LLD_A >= 1.
*
* Let K be the number of rows of a matrix A starting at the global in-
* dex IA,i.e, A( IA:IA+K-1, : ). Lr( IA, K ) denotes the number of rows
* that the process of row coordinate MYROW ( 0 <= MYROW < NPROW ) would
* receive if these K rows were distributed over NPROW processes. If K
* is the number of columns of a matrix A starting at the global index
* JA, i.e, A( :, JA:JA+K-1, : ), Lc( JA, K ) denotes the number of co-
* lumns that the process MYCOL ( 0 <= MYCOL < NPCOL ) would receive if
* these K columns were distributed over NPCOL processes.
*
* The values of Lr() and Lc() may be determined via a call to the func-
* tion PB_Cnumroc:
* Lr( IA, K ) = PB_Cnumroc( K, IA, MB_A, MB_A, MYROW, RSRC_A, NPROW )
* Lc( JA, K ) = PB_Cnumroc( K, JA, NB_A, NB_A, MYCOL, CSRC_A, NPCOL )
*
* A description vector is associated with each 2D block-cyclicly dis-
* tributed matrix. This vector stores the information required to
* establish the mapping between a matrix entry and its corresponding
* process and memory location.
*
* In the following comments, the character _ should be read as
* "of the distributed matrix". Let A be a generic term for any 2D
* block cyclicly distributed matrix. Its description vector is DESC_A:
*
* NOTATION STORED IN EXPLANATION
* ---------------- --------------- ------------------------------------
* DTYPE_A (global) DESCA[ DTYPE_ ] The descriptor type.
* CTXT_A (global) DESCA[ CTXT_ ] The BLACS context handle, indicating
* the NPROW x NPCOL BLACS process grid
* A is distributed over. The context
* itself is global, but the handle
* (the integer value) may vary.
* M_A (global) DESCA[ M_ ] The number of rows in the distribu-
* ted matrix A, M_A >= 0.
* N_A (global) DESCA[ N_ ] The number of columns in the distri-
* buted matrix A, N_A >= 0.
* IMB_A (global) DESCA[ IMB_ ] The number of rows of the upper left
* block of the matrix A, IMB_A > 0.
* INB_A (global) DESCA[ INB_ ] The number of columns of the upper
* left block of the matrix A,
* INB_A > 0.
* MB_A (global) DESCA[ MB_ ] The blocking factor used to distri-
* bute the last M_A-IMB_A rows of A,
* MB_A > 0.
* NB_A (global) DESCA[ NB_ ] The blocking factor used to distri-
* bute the last N_A-INB_A columns of
* A, NB_A > 0.
* RSRC_A (global) DESCA[ RSRC_ ] The process row over which the first
* row of the matrix A is distributed,
* NPROW > RSRC_A >= 0.
* CSRC_A (global) DESCA[ CSRC_ ] The process column over which the
* first column of A is distributed.
* NPCOL > CSRC_A >= 0.
* LLD_A (local) DESCA[ LLD_ ] The leading dimension of the local
* array storing the local blocks of
* the distributed matrix A,
* IF( Lc( 1, N_A ) > 0 )
* LLD_A >= MAX( 1, Lr( 1, M_A ) )
* ELSE
* LLD_A >= 1.
*
* Let K be the number of rows of a matrix A starting at the global in-
* dex IA,i.e, A( IA:IA+K-1, : ). Lr( IA, K ) denotes the number of rows
* that the process of row coordinate MYROW ( 0 <= MYROW < NPROW ) would
* receive if these K rows were distributed over NPROW processes. If K
* is the number of columns of a matrix A starting at the global index
* JA, i.e, A( :, JA:JA+K-1, : ), Lc( JA, K ) denotes the number of co-
* lumns that the process MYCOL ( 0 <= MYCOL < NPCOL ) would receive if
* these K columns were distributed over NPCOL processes.
*
* The values of Lr() and Lc() may be determined via a call to the func-
* tion PB_Cnumroc:
* Lr( IA, K ) = PB_Cnumroc( K, IA, IMB_A, MB_A, MYROW, RSRC_A, NPROW )
* Lc( JA, K ) = PB_Cnumroc( K, JA, INB_A, NB_A, MYCOL, CSRC_A, NPCOL )
*
* Arguments
* =========
*
* IF (global input) INTEGER
* On entry, IF specifies the global row Fortran index of the
* distributed subarray described by DESCIN. IF must be at least
* one.
*
* JF (global input) INTEGER
* On entry, JF specifies the global column Fortran index of
* the distributed subarray described by DESCIN. JF must be at
* least one.
*
* DESCIN (global and local input) INTEGER array
* On entry, DESCIN is an array of dimension DLEN1_ or DLEN_ as
* specified by its first entry DESCIN( DTYPE_ ). DESCIN is the
* source array descriptor of type BLOCK_CYCLIC_2D or of type
* BLOCK_CYCLIC_2D_INB.
*
* IC (global output) INTEGER
* On exit, IC specifies the global row C index of the distribu-
* ted subarray described by DESCOUT. IC = IF - 1, i.e IC is at
* least zero.
*
* JC (global output) INTEGER
* On entry, JC specifies the global column Fortran index of
* the distributed subarray described by DESCOUT. JC = JF - 1,
* i.e JC is at least zero.
*
* DESCOUT (global and local output) INTEGER array
* On entry, DESCOUT is an array of dimension DLEN_. DESCOUT is
* the target array descriptor of type BLOCK_CYCLIC_2D_INB.
*
* -- Written on April 1, 1998 by
* Antoine Petitet, University of Tennessee, Knoxville 37996, USA.
*
* ---------------------------------------------------------------------
*/
/* ..
* .. Executable Statements ..
*
*/
*IC = IF - 1;
*JC = JF - 1;
if ( DESCIN[DTYPE_] == BLOCK_CYCLIC_2D )
{
DESCOUT[DTYPE_] = BLOCK_CYCLIC_2D_INB;
DESCOUT[M_ ] = DESCIN[M1_ ];
DESCOUT[N_ ] = DESCIN[N1_ ];
DESCOUT[IMB_ ] = DESCIN[MB1_ ];
DESCOUT[INB_ ] = DESCIN[NB1_ ];
DESCOUT[MB_ ] = DESCIN[MB1_ ];
DESCOUT[NB_ ] = DESCIN[NB1_ ];
DESCOUT[RSRC_ ] = DESCIN[RSRC1_ ];
DESCOUT[CSRC_ ] = DESCIN[CSRC1_ ];
DESCOUT[CTXT_ ] = DESCIN[CTXT1_ ];
DESCOUT[LLD_ ] = DESCIN[LLD1_ ];
}
else if ( DESCIN[DTYPE_] == BLOCK_CYCLIC_2D_INB )
{
DESCOUT[DTYPE_] = BLOCK_CYCLIC_2D_INB;
DESCOUT[M_ ] = DESCIN[M_ ];
DESCOUT[N_ ] = DESCIN[N_ ];
DESCOUT[IMB_ ] = DESCIN[IMB_ ];
DESCOUT[INB_ ] = DESCIN[INB_ ];
DESCOUT[MB_ ] = DESCIN[MB_ ];
DESCOUT[NB_ ] = DESCIN[NB_ ];
DESCOUT[RSRC_ ] = DESCIN[RSRC_ ];
DESCOUT[CSRC_ ] = DESCIN[CSRC_ ];
DESCOUT[CTXT_ ] = DESCIN[CTXT_ ];
DESCOUT[LLD_ ] = DESCIN[LLD_ ];
}
else
{
DESCOUT[DTYPE_] = DESCIN[0];
DESCOUT[CTXT_ ] = DESCIN[1];
DESCOUT[M_ ] = 0;
DESCOUT[N_ ] = 0;
DESCOUT[IMB_ ] = 1;
DESCOUT[INB_ ] = 1;
DESCOUT[MB_ ] = 1;
DESCOUT[NB_ ] = 1;
DESCOUT[RSRC_ ] = 0;
DESCOUT[CSRC_ ] = 0;
DESCOUT[LLD_ ] = 1;
}
/*
* End of PB_CargFtoC
*/
}
