/************************************************************************* * This function takes a bisection and constructs a minimum weight vertex * separator out of it. It uses the node-based separator refinement for it. **************************************************************************/ void ConstructSeparator(CtrlType *ctrl, GraphType *graph, float ubfactor) { int i, j, k, nvtxs, nbnd; idxtype *xadj, *where, *bndind; nvtxs = graph->nvtxs; xadj = graph->xadj; nbnd = graph->nbnd; bndind = graph->bndind; where = idxcopy(nvtxs, graph->where, idxwspacemalloc(ctrl, nvtxs)); /* Put the nodes in the boundary into the separator */ for (i=0; i<nbnd; i++) { j = bndind[i]; if (xadj[j+1]-xadj[j] > 0) /* Ignore islands */ where[j] = 2; } GKfree(&graph->rdata, LTERM); Allocate2WayNodePartitionMemory(ctrl, graph); idxcopy(nvtxs, where, graph->where); idxwspacefree(ctrl, nvtxs); ASSERT(IsSeparable(graph)); Compute2WayNodePartitionParams(ctrl, graph); ASSERT(CheckNodePartitionParams(graph)); FM_2WayNodeRefine(ctrl, graph, ubfactor, 8); ASSERT(IsSeparable(graph)); }
IsoString Filter::ToSource() const { IsoString s; if ( IsValid() ) { if ( IsSeparable() ) { s += "SeparableFilter {\n"; s += " name { " + Separable().Name().ToUTF8() + " }\n"; s += " row-vector { "; SeparableFilter::coefficient_vector H = Separable().RowFilter(); for ( int i = 0; i < H.Length(); ++i ) s.AppendFormat( ( H[i] < 0 ) ? "%.6f " : " %.6f ", H[i] ); s += "}\n"; s += " col-vector { "; SeparableFilter::coefficient_vector V = Separable().ColFilter(); for ( int i = 0; i < V.Length(); ++i ) s.AppendFormat( ( V[i] < 0 ) ? "%.6f " : " %.6f ", V[i] ); s += "}\n"; } else { s += "KernelFilter {\n"; s += " name { " + Kernel().Name().ToUTF8() + " }\n"; s += " coefficients {\n"; KernelFilter::coefficient_matrix M = Kernel().Coefficients(); for ( int i = 0; i < M.Rows(); ++i ) { s += " "; for ( int j = 0; ; ) { s.AppendFormat( ( M[i][j] < 0 ) ? "%.6f " : " %.6f ", M[i][j] ); if ( ++j == M.Cols() ) break; s += ' '; } s += '\n'; } s += " }\n"; } s += "}\n"; } return s; }
/************************************************************************* * This function takes a bisection and constructs a minimum weight vertex * separator out of it. It uses an unweighted minimum-cover algorithm * followed by node-based separator refinement. **************************************************************************/ void ConstructMinCoverSeparator0(CtrlType *ctrl, GraphType *graph, float ubfactor) { int i, ii, j, jj, k, l, nvtxs, nbnd, bnvtxs[3], bnedges[2], csize; idxtype *xadj, *adjncy, *bxadj, *badjncy; idxtype *where, *bndind, *bndptr, *vmap, *ivmap, *cover; nvtxs = graph->nvtxs; xadj = graph->xadj; adjncy = graph->adjncy; nbnd = graph->nbnd; bndind = graph->bndind; bndptr = graph->bndptr; where = graph->where; vmap = idxwspacemalloc(ctrl, nvtxs); ivmap = idxwspacemalloc(ctrl, nbnd); cover = idxwspacemalloc(ctrl, nbnd); if (nbnd > 0) { /* Go through the boundary and determine the sizes of the bipartite graph */ bnvtxs[0] = bnvtxs[1] = bnedges[0] = bnedges[1] = 0; for (i=0; i<nbnd; i++) { j = bndind[i]; k = where[j]; if (xadj[j+1]-xadj[j] > 0) { bnvtxs[k]++; bnedges[k] += xadj[j+1]-xadj[j]; } } bnvtxs[2] = bnvtxs[0]+bnvtxs[1]; bnvtxs[1] = bnvtxs[0]; bnvtxs[0] = 0; bxadj = idxmalloc(bnvtxs[2]+1, "ConstructMinCoverSeparator: bxadj"); badjncy = idxmalloc(bnedges[0]+bnedges[1]+1, "ConstructMinCoverSeparator: badjncy"); /* Construct the ivmap and vmap */ ASSERT(idxset(nvtxs, -1, vmap) == vmap); for (i=0; i<nbnd; i++) { j = bndind[i]; k = where[j]; if (xadj[j+1]-xadj[j] > 0) { vmap[j] = bnvtxs[k]; ivmap[bnvtxs[k]++] = j; } } /* OK, go through and put the vertices of each part starting from 0 */ bnvtxs[1] = bnvtxs[0]; bnvtxs[0] = 0; bxadj[0] = l = 0; for (k=0; k<2; k++) { for (ii=0; ii<nbnd; ii++) { i = bndind[ii]; if (where[i] == k && xadj[i] < xadj[i+1]) { for (j=xadj[i]; j<xadj[i+1]; j++) { jj = adjncy[j]; if (where[jj] != k) { ASSERT(bndptr[jj] != -1); ASSERTP(vmap[jj] != -1, ("%d %d %d\n", jj, vmap[jj], graph->bndptr[jj])); badjncy[l++] = vmap[jj]; } } bxadj[++bnvtxs[k]] = l; } } } ASSERT(l <= bnedges[0]+bnedges[1]); MinCover(bxadj, badjncy, bnvtxs[0], bnvtxs[1], cover, &csize); IFSET(ctrl->dbglvl, DBG_SEPINFO, printf("Nvtxs: %6d, [%5d %5d], Cut: %6d, SS: [%6d %6d], Cover: %6d\n", nvtxs, graph->pwgts[0], graph->pwgts[1], graph->mincut, bnvtxs[0], bnvtxs[1]-bnvtxs[0], csize)); for (i=0; i<csize; i++) { j = ivmap[cover[i]]; where[j] = 2; } GKfree(&bxadj, &badjncy, LTERM); for (i=0; i<nbnd; i++) bndptr[bndind[i]] = -1; for (nbnd=i=0; i<nvtxs; i++) { if (where[i] == 2) { bndind[nbnd] = i; bndptr[i] = nbnd++; } } } else { IFSET(ctrl->dbglvl, DBG_SEPINFO, printf("Nvtxs: %6d, [%5d %5d], Cut: %6d, SS: [%6d %6d], Cover: %6d\n", nvtxs, graph->pwgts[0], graph->pwgts[1], graph->mincut, 0, 0, 0)); } idxwspacefree(ctrl, nvtxs); idxwspacefree(ctrl, graph->nbnd); idxwspacefree(ctrl, graph->nbnd); graph->nbnd = nbnd; ASSERT(IsSeparable(graph)); }