Esempio n. 1
0
int main(int argc, char *argv[])
{
  ssize_t i, j, niter;
  params_t *params;
  gk_csr_t *mat;
  FILE *fpout;
 
  /* get command-line options */
  params = parse_cmdline(argc, argv);

  /* read the data */
  mat = gk_csr_Read(params->infile, GK_CSR_FMT_METIS, 1, 1);

  /* display some basic stats */
  print_init_info(params, mat);



  if (params->ntvs != -1) {
    /* compute the pr for different randomly generated restart-distribution vectors */
    float **prs;

    prs = gk_fAllocMatrix(params->ntvs, mat->nrows, 0.0, "main: prs");

    /* generate the random restart vectors */
    for (j=0; j<params->ntvs; j++) {
      for (i=0; i<mat->nrows; i++)
        prs[j][i] = RandomInRange(931);
      gk_fscale(mat->nrows, 1.0/gk_fsum(mat->nrows, prs[j], 1), prs[j], 1);

      niter = gk_rw_PageRank(mat, params->lamda, params->eps, params->niter, prs[j]);
      printf("tvs#: %zd; niters: %zd\n", j, niter);
    }

    /* output the computed pr scores */
    fpout = gk_fopen(params->outfile, "w", "main: outfile");
    for (i=0; i<mat->nrows; i++) {
      for (j=0; j<params->ntvs; j++) 
        fprintf(fpout, "%.4e ", prs[j][i]);
      fprintf(fpout, "\n");
    }
    gk_fclose(fpout);

    gk_fFreeMatrix(&prs, params->ntvs, mat->nrows);
  }
  else if (params->ppr != -1) {
    /* compute the personalized pr from the specified vertex */
    float *pr;

    pr = gk_fsmalloc(mat->nrows, 0.0, "main: pr");

    pr[params->ppr-1] = 1.0;

    niter = gk_rw_PageRank(mat, params->lamda, params->eps, params->niter, pr);
    printf("ppr: %d; niters: %zd\n", params->ppr, niter);

    /* output the computed pr scores */
    fpout = gk_fopen(params->outfile, "w", "main: outfile");
    for (i=0; i<mat->nrows; i++) 
      fprintf(fpout, "%.4e\n", pr[i]);
    gk_fclose(fpout);

    gk_free((void **)&pr, LTERM);
  }
  else {
    /* compute the standard pr */
    int jmax;
    float diff, maxdiff;
    float *pr;

    pr = gk_fsmalloc(mat->nrows, 1.0/mat->nrows, "main: pr");

    niter = gk_rw_PageRank(mat, params->lamda, params->eps, params->niter, pr);
    printf("pr; niters: %zd\n", niter);

    /* output the computed pr scores */
    fpout = gk_fopen(params->outfile, "w", "main: outfile");
    for (i=0; i<mat->nrows; i++) {
      for (jmax=i, maxdiff=0.0, j=mat->rowptr[i]; j<mat->rowptr[i+1]; j++) {
        if ((diff = fabs(pr[i]-pr[mat->rowind[j]])) > maxdiff) {
          maxdiff = diff;
          jmax = mat->rowind[j];
        }
      }
      fprintf(fpout, "%.4e %10zd %.4e %10d\n", pr[i], 
          mat->rowptr[i+1]-mat->rowptr[i], maxdiff, jmax+1);
    }
    gk_fclose(fpout);

    gk_free((void **)&pr, LTERM);
  }

  gk_csr_Free(&mat);

  /* display some final stats */
  print_final_info(params);
}
Esempio n. 2
0
/*************************************************************************
* This function takes a graph and produces a bisection of it
**************************************************************************/
idxtype MlevelRecursiveBisection(CtrlType *ctrl, GraphType *graph, 
          idxtype nparts, idxtype *part, float *tpwgts, float ubfactor, 
          idxtype fpart)
{
  idxtype i, j, nvtxs, cut, tvwgt, tpwgts2[2];
  idxtype *label, *where;
  GraphType lgraph, rgraph;
  float wsum;

  nvtxs = graph->nvtxs;
  if (nvtxs == 0) {
    mprintf("\t***Cannot bisect a graph with 0 vertices!\n\t***You are trying to partition a graph into too many parts!\n");
    return 0;
  }

  /* Determine the weights of the partitions */
  tvwgt = idxsum(nvtxs, graph->vwgt, 1);
  tpwgts2[0] = tvwgt*gk_fsum(nparts/2, tpwgts, 1);
  tpwgts2[1] = tvwgt-tpwgts2[0];

  MlevelEdgeBisection(ctrl, graph, tpwgts2, ubfactor);
  cut = graph->mincut;

  /* mprintf("%5D %5D %5D [%5D %f]\n", tpwgts2[0], tpwgts2[1], cut, tvwgt, gk_fsum(nparts/2, tpwgts, 1));*/

  label = graph->label;
  where = graph->where;
  for (i=0; i<nvtxs; i++)
    part[label[i]] = where[i] + fpart;

  if (nparts > 2) {
    SplitGraphPart(ctrl, graph, &lgraph, &rgraph);
    /* mprintf("%D %D\n", lgraph.nvtxs, rgraph.nvtxs); */
  }


  /* Free the memory of the top level graph */
  FreeGraph(graph, 0);

  /* Scale the fractions in the tpwgts according to the true weight */
  wsum = gk_fsum(nparts/2, tpwgts, 1);
  gk_fscale(nparts/2, 1.0/wsum, tpwgts, 1);
  gk_fscale(nparts-nparts/2, 1.0/(1.0-wsum), tpwgts+nparts/2, 1);
  /*
  for (i=0; i<nparts; i++)
    mprintf("%5.3f ", tpwgts[i]);
  mprintf("[%5.3f]\n", wsum);
  */

  /* Do the recursive call */
  if (nparts > 3) {
    cut += MlevelRecursiveBisection(ctrl, &lgraph, nparts/2, part, tpwgts, ubfactor, fpart);
    cut += MlevelRecursiveBisection(ctrl, &rgraph, nparts-nparts/2, part, tpwgts+nparts/2, ubfactor, fpart+nparts/2);
  }
  else if (nparts == 3) {
    cut += MlevelRecursiveBisection(ctrl, &rgraph, nparts-nparts/2, part, tpwgts+nparts/2, ubfactor, fpart+nparts/2);
    FreeGraph(&lgraph, 0);
  }

  return cut;
}