| 1 | /* $Id$ $Revision$ */ | 
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| 2 | /* vim:set shiftwidth=4 ts=8: */ | 
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| 3 |  | 
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| 4 | /************************************************************************* | 
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| 5 | * Copyright (c) 2011 AT&T Intellectual Property | 
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| 6 | * All rights reserved. This program and the accompanying materials | 
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| 7 | * are made available under the terms of the Eclipse Public License v1.0 | 
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| 8 | * which accompanies this distribution, and is available at | 
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| 9 | * http://www.eclipse.org/legal/epl-v10.html | 
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| 10 | * | 
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| 11 | * Contributors: See CVS logs. Details at http://www.graphviz.org/ | 
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| 12 | *************************************************************************/ | 
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| 13 |  | 
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| 14 |  | 
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| 15 | #include "dot.h" | 
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| 16 |  | 
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| 17 | static node_t* | 
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| 18 | map_interclust_node(node_t * n) | 
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| 19 | { | 
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| 20 | node_t *rv; | 
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| 21 |  | 
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| 22 | if ((ND_clust(n) == NULL) || (  GD_expanded(ND_clust(n))) ) | 
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| 23 | rv = n; | 
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| 24 | else | 
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| 25 | rv = GD_rankleader(ND_clust(n))[ND_rank(n)]; | 
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| 26 | return rv; | 
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| 27 | } | 
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| 28 |  | 
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| 29 | /* make d slots starting at position pos (where 1 already exists) */ | 
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| 30 | static void | 
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| 31 | make_slots(graph_t * root, int r, int pos, int d) | 
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| 32 | { | 
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| 33 | int i; | 
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| 34 | node_t *v, **vlist; | 
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| 35 | vlist = GD_rank(root)[r].v; | 
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| 36 | if (d <= 0) { | 
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| 37 | for (i = pos - d + 1; i < GD_rank(root)[r].n; i++) { | 
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| 38 | v = vlist[i]; | 
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| 39 | ND_order(v) = i + d - 1; | 
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| 40 | vlist[ND_order(v)] = v; | 
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| 41 | } | 
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| 42 | for (i = GD_rank(root)[r].n + d - 1; i < GD_rank(root)[r].n; i++) | 
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| 43 | vlist[i] = NULL; | 
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| 44 | } else { | 
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| 45 | /*assert(ND_rank(root)[r].n + d - 1 <= ND_rank(root)[r].an);*/ | 
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| 46 | for (i = GD_rank(root)[r].n - 1; i > pos; i--) { | 
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| 47 | v = vlist[i]; | 
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| 48 | ND_order(v) = i + d - 1; | 
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| 49 | vlist[ND_order(v)] = v; | 
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| 50 | } | 
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| 51 | for (i = pos + 1; i < pos + d; i++) | 
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| 52 | vlist[i] = NULL; | 
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| 53 | } | 
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| 54 | GD_rank(root)[r].n += d - 1; | 
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| 55 | } | 
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| 56 |  | 
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| 57 | static node_t* | 
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| 58 | clone_vn(graph_t * g, node_t * vn) | 
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| 59 | { | 
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| 60 | node_t *rv; | 
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| 61 | int r; | 
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| 62 |  | 
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| 63 | r = ND_rank(vn); | 
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| 64 | make_slots(g, r, ND_order(vn), 2); | 
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| 65 | rv = virtual_node(g); | 
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| 66 | ND_lw(rv) = ND_lw(vn); | 
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| 67 | ND_rw(rv) = ND_rw(vn); | 
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| 68 | ND_rank(rv) = ND_rank(vn); | 
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| 69 | ND_order(rv) = ND_order(vn) + 1; | 
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| 70 | GD_rank(g)[r].v[ND_order(rv)] = rv; | 
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| 71 | return rv; | 
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| 72 | } | 
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| 73 |  | 
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| 74 | static void | 
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| 75 | map_path(node_t * from, node_t * to, edge_t * orig, edge_t * ve, int type) | 
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| 76 | { | 
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| 77 | int r; | 
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| 78 | node_t *u, *v; | 
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| 79 | edge_t *e; | 
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| 80 |  | 
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| 81 | assert(ND_rank(from) < ND_rank(to)); | 
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| 82 |  | 
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| 83 | if ((agtail(ve) == from) && (aghead(ve) == to)) | 
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| 84 | return; | 
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| 85 |  | 
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| 86 | if (ED_count(ve) > 1) { | 
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| 87 | ED_to_virt(orig) = NULL; | 
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| 88 | if (ND_rank(to) - ND_rank(from) == 1) { | 
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| 89 | if ((e = find_fast_edge(from, to)) && (ports_eq(orig, e))) { | 
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| 90 | merge_oneway(orig, e); | 
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| 91 | if ((ND_node_type(from) == NORMAL) | 
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| 92 | && (ND_node_type(to) == NORMAL)) | 
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| 93 | other_edge(orig); | 
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| 94 | return; | 
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| 95 | } | 
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| 96 | } | 
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| 97 | u = from; | 
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| 98 | for (r = ND_rank(from); r < ND_rank(to); r++) { | 
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| 99 | if (r < ND_rank(to) - 1) | 
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| 100 | v = clone_vn(dot_root(from), aghead(ve)); | 
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| 101 | else | 
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| 102 | v = to; | 
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| 103 | e = virtual_edge(u, v, orig); | 
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| 104 | ED_edge_type(e) = type; | 
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| 105 | u = v; | 
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| 106 | ED_count(ve)--; | 
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| 107 | ve = ND_out(aghead(ve)).list[0]; | 
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| 108 | } | 
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| 109 | } else { | 
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| 110 | if (ND_rank(to) - ND_rank(from) == 1) { | 
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| 111 | if ((ve = find_fast_edge(from, to)) && (ports_eq(orig, ve))) { | 
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| 112 | /*ED_to_orig(ve) = orig; */ | 
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| 113 | ED_to_virt(orig) = ve; | 
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| 114 | ED_edge_type(ve) = type; | 
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| 115 | ED_count(ve)++; | 
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| 116 | if ((ND_node_type(from) == NORMAL) | 
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| 117 | && (ND_node_type(to) == NORMAL)) | 
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| 118 | other_edge(orig); | 
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| 119 | } else { | 
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| 120 | ED_to_virt(orig) = NULL; | 
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| 121 | ve = virtual_edge(from, to, orig); | 
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| 122 | ED_edge_type(ve) = type; | 
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| 123 | } | 
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| 124 | } | 
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| 125 | if (ND_rank(to) - ND_rank(from) > 1) { | 
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| 126 | e = ve; | 
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| 127 | if (agtail(ve) != from) { | 
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| 128 | ED_to_virt(orig) = NULL; | 
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| 129 | e = ED_to_virt(orig) = virtual_edge(from, aghead(ve), orig); | 
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| 130 | delete_fast_edge(ve); | 
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| 131 | } else | 
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| 132 | e = ve; | 
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| 133 | while (ND_rank(aghead(e)) != ND_rank(to)) | 
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| 134 | e = ND_out(aghead(e)).list[0]; | 
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| 135 | if (aghead(e) != to) { | 
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| 136 | ve = e; | 
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| 137 | e = virtual_edge(agtail(e), to, orig); | 
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| 138 | ED_edge_type(e) = type; | 
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| 139 | delete_fast_edge(ve); | 
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| 140 | } | 
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| 141 | } | 
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| 142 | } | 
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| 143 | } | 
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| 144 |  | 
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| 145 | static void | 
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| 146 | make_interclust_chain(graph_t * g, node_t * from, node_t * to, edge_t * orig) | 
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| 147 | { | 
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| 148 | int newtype; | 
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| 149 | node_t *u, *v; | 
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| 150 |  | 
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| 151 | u = map_interclust_node(from); | 
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| 152 | v = map_interclust_node(to); | 
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| 153 | if ((u == from) && (v == to)) | 
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| 154 | newtype = VIRTUAL; | 
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| 155 | else | 
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| 156 | newtype = CLUSTER_EDGE; | 
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| 157 | map_path(u, v, orig, ED_to_virt(orig), newtype); | 
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| 158 | } | 
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| 159 |  | 
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| 160 | /* | 
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| 161 | * attach and install edges between clusters. | 
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| 162 | * essentially, class2() for interclust edges. | 
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| 163 | */ | 
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| 164 | void interclexp(graph_t * subg) | 
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| 165 | { | 
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| 166 | graph_t *g; | 
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| 167 | node_t *n; | 
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| 168 | edge_t *e, *prev, *next; | 
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| 169 |  | 
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| 170 | g = dot_root(subg); | 
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| 171 | for (n = agfstnode(subg); n; n = agnxtnode(subg, n)) { | 
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| 172 |  | 
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| 173 | /* N.B. n may be in a sub-cluster of subg */ | 
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| 174 | prev = NULL; | 
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| 175 | for (e = agfstedge(g, n); e; e = next) { | 
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| 176 | next = agnxtedge(g, e, n); | 
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| 177 | if (agcontains(subg, e)) | 
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| 178 | continue; | 
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| 179 |  | 
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| 180 | /* canonicalize edge */ | 
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| 181 | e = AGMKOUT(e); | 
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| 182 | /* short/flat multi edges */ | 
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| 183 | if (mergeable(prev, e)) { | 
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| 184 | if (ND_rank(agtail(e)) == ND_rank(aghead(e))) | 
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| 185 | ED_to_virt(e) = prev; | 
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| 186 | else | 
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| 187 | ED_to_virt(e) = NULL; | 
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| 188 | if (ED_to_virt(prev) == NULL) | 
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| 189 | continue;	/* internal edge */ | 
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| 190 | merge_chain(subg, e, ED_to_virt(prev), FALSE); | 
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| 191 | safe_other_edge(e); | 
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| 192 | continue; | 
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| 193 | } | 
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| 194 |  | 
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| 195 | /* flat edges */ | 
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| 196 | if (ND_rank(agtail(e)) == ND_rank(aghead(e))) { | 
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| 197 | edge_t* fe; | 
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| 198 | if ((fe = find_flat_edge(agtail(e), aghead(e))) == NULL) { | 
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| 199 | flat_edge(g, e); | 
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| 200 | prev = e; | 
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| 201 | } else if (e != fe) { | 
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| 202 | safe_other_edge(e); | 
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| 203 | if (!ED_to_virt(e)) merge_oneway(e, fe); | 
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| 204 | } | 
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| 205 | continue; | 
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| 206 | } | 
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| 207 |  | 
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| 208 | /* forward edges */ | 
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| 209 | if (ND_rank(aghead(e)) > ND_rank(agtail(e))) { | 
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| 210 | make_interclust_chain(g, agtail(e), aghead(e), e); | 
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| 211 | prev = e; | 
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| 212 | continue; | 
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| 213 | } | 
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| 214 |  | 
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| 215 | /* backward edges */ | 
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| 216 | else { | 
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| 217 | /* | 
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| 218 | I think that make_interclust_chain should create call other_edge(e) anyway | 
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| 219 | if (agcontains(subg,agtail(e)) | 
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| 220 | && agfindedge(g,aghead(e),agtail(e))) other_edge(e); | 
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| 221 | */ | 
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| 222 | make_interclust_chain(g, aghead(e), agtail(e), e); | 
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| 223 | prev = e; | 
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| 224 | } | 
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| 225 | } | 
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| 226 | } | 
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| 227 | } | 
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| 228 |  | 
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| 229 | static void | 
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| 230 | merge_ranks(graph_t * subg) | 
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| 231 | { | 
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| 232 | int i, d, r, pos, ipos; | 
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| 233 | node_t *v; | 
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| 234 | graph_t *root; | 
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| 235 |  | 
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| 236 | root = dot_root(subg); | 
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| 237 | if (GD_minrank(subg) > 0) | 
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| 238 | GD_rank(root)[GD_minrank(subg) - 1].valid = FALSE; | 
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| 239 | for (r = GD_minrank(subg); r <= GD_maxrank(subg); r++) { | 
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| 240 | d = GD_rank(subg)[r].n; | 
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| 241 | ipos = pos = ND_order(GD_rankleader(subg)[r]); | 
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| 242 | make_slots(root, r, pos, d); | 
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| 243 | for (i = 0; i < GD_rank(subg)[r].n; i++) { | 
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| 244 | v = GD_rank(root)[r].v[pos] = GD_rank(subg)[r].v[i]; | 
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| 245 | ND_order(v) = pos++; | 
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| 246 | /* real nodes automatically have v->root = root graph */ | 
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| 247 | if (ND_node_type(v) == VIRTUAL) | 
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| 248 | v->root = agroot(root); | 
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| 249 | delete_fast_node(subg, v); | 
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| 250 | fast_node(root, v); | 
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| 251 | GD_n_nodes(root)++; | 
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| 252 | } | 
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| 253 | GD_rank(subg)[r].v = GD_rank(root)[r].v + ipos; | 
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| 254 | GD_rank(root)[r].valid = FALSE; | 
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| 255 | } | 
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| 256 | if (r < GD_maxrank(root)) | 
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| 257 | GD_rank(root)[r].valid = FALSE; | 
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| 258 | GD_expanded(subg) = TRUE; | 
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| 259 | } | 
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| 260 |  | 
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| 261 | static void | 
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| 262 | remove_rankleaders(graph_t * g) | 
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| 263 | { | 
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| 264 | int r; | 
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| 265 | node_t *v; | 
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| 266 | edge_t *e; | 
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| 267 |  | 
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| 268 | for (r = GD_minrank(g); r <= GD_maxrank(g); r++) { | 
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| 269 | v = GD_rankleader(g)[r]; | 
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| 270 |  | 
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| 271 | /* remove the entire chain */ | 
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| 272 | while ((e = ND_out(v).list[0])) | 
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| 273 | delete_fast_edge(e); | 
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| 274 | while ((e = ND_in(v).list[0])) | 
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| 275 | delete_fast_edge(e); | 
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| 276 | delete_fast_node(dot_root(g), v); | 
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| 277 | GD_rankleader(g)[r] = NULL; | 
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| 278 | } | 
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| 279 | } | 
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| 280 |  | 
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| 281 | /* delete virtual nodes of a cluster, and install real nodes or sub-clusters */ | 
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| 282 | void expand_cluster(graph_t * subg) | 
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| 283 | { | 
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| 284 | /* build internal structure of the cluster */ | 
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| 285 | class2(subg); | 
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| 286 | GD_comp(subg).size = 1; | 
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| 287 | GD_comp(subg).list[0] = GD_nlist(subg); | 
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| 288 | allocate_ranks(subg); | 
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| 289 | build_ranks(subg, 0); | 
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| 290 | merge_ranks(subg); | 
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| 291 |  | 
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| 292 | /* build external structure of the cluster */ | 
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| 293 | interclexp(subg); | 
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| 294 | remove_rankleaders(subg); | 
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| 295 | } | 
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| 296 |  | 
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| 297 | /* this function marks every node in <g> with its top-level cluster under <g> */ | 
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| 298 | void mark_clusters(graph_t * g) | 
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| 299 | { | 
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| 300 | int c; | 
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| 301 | node_t *n, *nn, *vn; | 
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| 302 | edge_t *orig, *e; | 
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| 303 | graph_t *clust; | 
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| 304 |  | 
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| 305 | /* remove sub-clusters below this level */ | 
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| 306 | for (n = agfstnode(g); n; n = agnxtnode(g, n)) { | 
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| 307 | if (ND_ranktype(n) == CLUSTER) | 
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| 308 | UF_singleton(n); | 
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| 309 | ND_clust(n) = NULL; | 
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| 310 | } | 
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| 311 |  | 
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| 312 | for (c = 1; c <= GD_n_cluster(g); c++) { | 
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| 313 | clust = GD_clust(g)[c]; | 
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| 314 | for (n = agfstnode(clust); n; n = nn) { | 
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| 315 | nn = agnxtnode(clust,n); | 
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| 316 | if (ND_ranktype(n) != NORMAL) { | 
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| 317 | agerr(AGWARN, | 
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| 318 | "%s was already in a rankset, deleted from cluster %s\n", | 
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| 319 | agnameof(n), agnameof(g)); | 
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| 320 | agdelete(clust,n); | 
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| 321 | continue; | 
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| 322 | } | 
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| 323 | UF_setname(n, GD_leader(clust)); | 
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| 324 | ND_clust(n) = clust; | 
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| 325 | ND_ranktype(n) = CLUSTER; | 
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| 326 |  | 
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| 327 | /* here we mark the vnodes of edges in the cluster */ | 
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| 328 | for (orig = agfstout(clust, n); orig; | 
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| 329 | orig = agnxtout(clust, orig)) { | 
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| 330 | if ((e = ED_to_virt(orig))) { | 
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| 331 | while (e && ND_node_type(vn =aghead(e)) == VIRTUAL) { | 
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| 332 | ND_clust(vn) = clust; | 
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| 333 | e = ND_out(aghead(e)).list[0]; | 
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| 334 | /* trouble if concentrators and clusters are mixed */ | 
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| 335 | } | 
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| 336 | } | 
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| 337 | } | 
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| 338 | } | 
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| 339 | } | 
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| 340 | } | 
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| 341 |  | 
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| 342 | void build_skeleton(graph_t * g, graph_t * subg) | 
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| 343 | { | 
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| 344 | int r; | 
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| 345 | node_t *v, *prev, *rl; | 
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| 346 | edge_t *e; | 
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| 347 |  | 
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| 348 | prev = NULL; | 
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| 349 | GD_rankleader(subg) = N_NEW(GD_maxrank(subg) + 2, node_t *); | 
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| 350 | for (r = GD_minrank(subg); r <= GD_maxrank(subg); r++) { | 
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| 351 | v = GD_rankleader(subg)[r] = virtual_node(g); | 
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| 352 | ND_rank(v) = r; | 
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| 353 | ND_ranktype(v) = CLUSTER; | 
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| 354 | ND_clust(v) = subg; | 
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| 355 | if (prev) { | 
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| 356 | e = virtual_edge(prev, v, NULL); | 
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| 357 | ED_xpenalty(e) *= CL_CROSS; | 
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| 358 | } | 
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| 359 | prev = v; | 
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| 360 | } | 
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| 361 |  | 
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| 362 | /* set the counts on virtual edges of the cluster skeleton */ | 
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| 363 | for (v = agfstnode(subg); v; v = agnxtnode(subg, v)) { | 
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| 364 | rl = GD_rankleader(subg)[ND_rank(v)]; | 
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| 365 | ND_UF_size(rl)++; | 
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| 366 | for (e = agfstout(subg, v); e; e = agnxtout(subg, e)) { | 
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| 367 | for (r = ND_rank(agtail(e)); r < ND_rank(aghead(e)); r++) { | 
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| 368 | ED_count(ND_out(rl).list[0])++; | 
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| 369 | } | 
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| 370 | } | 
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| 371 | } | 
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| 372 | for (r = GD_minrank(subg); r <= GD_maxrank(subg); r++) { | 
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| 373 | rl = GD_rankleader(subg)[r]; | 
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| 374 | if (ND_UF_size(rl) > 1) | 
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| 375 | ND_UF_size(rl)--; | 
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| 376 | } | 
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| 377 | } | 
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| 378 |  | 
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| 379 | void install_cluster(graph_t * g, node_t * n, int pass, nodequeue * q) | 
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| 380 | { | 
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| 381 | int r; | 
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| 382 | graph_t *clust; | 
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| 383 |  | 
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| 384 | clust = ND_clust(n); | 
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| 385 | if (GD_installed(clust) != pass + 1) { | 
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| 386 | for (r = GD_minrank(clust); r <= GD_maxrank(clust); r++) | 
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| 387 | install_in_rank(g, GD_rankleader(clust)[r]); | 
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| 388 | for (r = GD_minrank(clust); r <= GD_maxrank(clust); r++) | 
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| 389 | enqueue_neighbors(q, GD_rankleader(clust)[r], pass); | 
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| 390 | GD_installed(clust) = pass + 1; | 
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| 391 | } | 
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| 392 | } | 
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| 393 |  | 
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| 394 | static void mark_lowcluster_basic(Agraph_t * g); | 
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| 395 | void mark_lowclusters(Agraph_t * root) | 
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| 396 | { | 
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| 397 | Agnode_t *n, *vn; | 
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| 398 | Agedge_t *orig, *e; | 
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| 399 |  | 
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| 400 | /* first, zap any previous cluster labelings */ | 
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| 401 | for (n = agfstnode(root); n; n = agnxtnode(root, n)) { | 
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| 402 | ND_clust(n) = NULL; | 
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| 403 | for (orig = agfstout(root, n); orig; orig = agnxtout(root, orig)) { | 
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| 404 | if ((e = ED_to_virt(orig))) { | 
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| 405 | while (e && (ND_node_type(vn = aghead(e))) == VIRTUAL) { | 
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| 406 | ND_clust(vn) = NULL; | 
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| 407 | e = ND_out(aghead(e)).list[0]; | 
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| 408 | } | 
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| 409 | } | 
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| 410 | } | 
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| 411 | } | 
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| 412 |  | 
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| 413 | /* do the recursion */ | 
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| 414 | mark_lowcluster_basic(root); | 
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| 415 | } | 
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| 416 |  | 
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| 417 | static void mark_lowcluster_basic(Agraph_t * g) | 
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| 418 | { | 
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| 419 | Agraph_t *clust; | 
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| 420 | Agnode_t *n, *vn; | 
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| 421 | Agedge_t *orig, *e; | 
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| 422 | int c; | 
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| 423 |  | 
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| 424 | for (c = 1; c <= GD_n_cluster(g); c++) { | 
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| 425 | clust = GD_clust(g)[c]; | 
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| 426 | mark_lowcluster_basic(clust); | 
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| 427 | } | 
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| 428 | /* see what belongs to this graph that wasn't already marked */ | 
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| 429 | for (n = agfstnode(g); n; n = agnxtnode(g, n)) { | 
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| 430 | if (ND_clust(n) == NULL) | 
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| 431 | ND_clust(n) = g; | 
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| 432 | for (orig = agfstout(g, n); orig; orig = agnxtout(g, orig)) { | 
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| 433 | if ((e = ED_to_virt(orig))) { | 
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| 434 | while (e && (ND_node_type(vn = aghead(e))) == VIRTUAL) { | 
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| 435 | if (ND_clust(vn) == NULL) | 
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| 436 | ND_clust(vn) = g; | 
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| 437 | e = ND_out(aghead(e)).list[0]; | 
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| 438 | } | 
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| 439 | } | 
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| 440 | } | 
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| 441 | } | 
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| 442 | } | 
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| 443 |  | 
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