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/* Copyright 2011 ENSEIRB, INRIA & CNRS
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** This file is part of the Scotch software package for static mapping,
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** graph partitioning and sparse matrix ordering.
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** This software is governed by the CeCILL-C license under French law
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** and abiding by the rules of distribution of free software. You can
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** use, modify and/or redistribute the software under the terms of the
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** CeCILL-C license as circulated by CEA, CNRS and INRIA at the following
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** URL: "http://www.cecill.info".
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** As a counterpart to the access to the source code and rights to copy,
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** modify and redistribute granted by the license, users are provided
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** only with a limited warranty and the software's author, the holder of
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** the economic rights, and the successive licensors have only limited
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** In this respect, the user's attention is drawn to the risks associated
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** with loading, using, modifying and/or developing or reproducing the
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** software by the user in light of its specific status of free software,
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** that may mean that it is complicated to manipulate, and that also
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** therefore means that it is reserved for developers and experienced
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** professionals having in-depth computer knowledge. Users are therefore
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** encouraged to load and test the software's suitability as regards
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** their requirements in conditions enabling the security of their
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** systems and/or data to be ensured and, more generally, to use and
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** operate it in the same conditions as regards security.
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** The fact that you are presently reading this means that you have had
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** knowledge of the CeCILL-C license and that you accept its terms.
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/************************************************************/
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/** NAME : library_dgraph_coarsen.c **/
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/** AUTHOR : Francois PELLEGRINI **/
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/** FUNCTION : This module is the API for the **/
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/** distributed graph coarsening routine of **/
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/** the libSCOTCH library. **/
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/** DATES : # Version 5.1 : from : 07 aug 2011 **/
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/** to 07 aug 2011 **/
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/************************************************************/
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** The defines and includes.
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#include "dgraph_coarsen.h"
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/************************************/
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/* This routine is the C API for */
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/* the distributed graph coarsening */
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/************************************/
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/*+ This routine creates a distributed coarse graph
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*** from the given fine graph, unless the coarse graph
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*** is smaller than some threshold size or the
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*** coarsening ratio is above some other threshold.
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*** If the coarse graph is created, a coarse-to-fine
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*** vertex array is created, that contains a pair of
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*** fine indices for each coarse index. It is the
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*** user's responsibility to free this array when it
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*** is no longer needed.
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*** - 0 : if the graph has been coarsened.
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*** - 1 : if the graph could not be coarsened.
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SCOTCH_dgraphCoarsen (
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SCOTCH_Dgraph * restrict const finegrafptr, /* Fine graph structure to fill */
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SCOTCH_Dgraph * restrict const coargrafptr, /* Coarse graph */
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SCOTCH_Num * restrict const multloctab, /* Pointer to multinode array */
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const SCOTCH_Num coarnbr, /* Minimum number of coarse vertices */
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const double coarrat) /* Maximum contraction ratio */
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DgraphCoarsenMulti * restrict multlocptr;
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o = dgraphCoarsen ((Dgraph * restrict const) finegrafptr, (Dgraph * restrict const) coargrafptr,
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&multlocptr, 5, coarnbr, 0, 0, coarrat);
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if (o == 0) { /* If coarsening succeeded */
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SCOTCH_Num coarvertnbr;
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SCOTCH_dgraphSize (coargrafptr, NULL, &coarvertnbr, NULL, NULL); /* Get number of local coarse vertices */
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memCpy (multloctab, multlocptr, coarvertnbr * 2 * sizeof (Gnum));
added
removed
src/libscotch/library_dgraph_coarsen.c
