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#!/usr/bin/env python |
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|
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# $Id: boostgraph.py,v 1.5 2008/02/22 13:34:26 joko Exp $ |
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|
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# (c) 2008 Andreas Motl <andreas.motl@ilo.de> |
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# (c) 2008 Sebastian Utz <su@rotamente.com> |
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|
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# This program is free software: you can redistribute it and/or modify |
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# it under the terms of the GNU Affero General Public License as published by |
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# the Free Software Foundation, either version 3 of the License, or |
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# (at your option) any later version. |
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# |
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# This program is distributed in the hope that it will be useful, |
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# but WITHOUT ANY WARRANTY; without even the implied warranty of |
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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# GNU Affero General Public License for more details. |
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# |
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# You should have received a copy of the GNU Affero General Public License |
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# along with this program. If not, see <http://www.gnu.org/licenses/>. |
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|
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|
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|
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# Uses BGL-Python (depth_first_search) |
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# |
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# BGL-Python Homepage: http://osl.iu.edu/~dgregor/bgl-python/ |
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# |
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# Documentation (Boost): |
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# - http://www.boost.org/libs/graph/doc/graph_theory_review.html |
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# - http://www.boost.org/libs/graph/doc/depth_first_search.html |
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# - http://www.boost.org/boost/graph/depth_first_search.hpp |
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# - http://www.boost.org/libs/graph/doc/DFSVisitor.html |
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# - http://www.boost.org/libs/graph/example/dfs-example.cpp |
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# |
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# Documentation (BGL-Python): |
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# - http://osl.iu.edu/~dgregor/bgl-python/reference/boost.graph.html |
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# |
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# Subversion-Repository: https://svn.osl.iu.edu/svn/projects_viz/bgl-python/ |
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|
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|
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RANDOM_MAX_NODES = 10 |
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RANDOM_MAX_CHILDREN_PER_NODE = 10 |
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MAX_SEARCH_DEPTH = 50 |
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|
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|
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DEBUG = True |
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DEBUG = False |
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|
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ENABLE_PROFILING = False |
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|
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if ENABLE_PROFILING: |
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import profile |
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from profile import Profile |
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|
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|
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import sys, os |
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import random |
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|
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sys.path.append('bgl_python') |
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os.environ['PATH'] += ';' + './bgl_python' |
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|
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import boost.graph as bgl |
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|
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|
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|
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# from http://www.boost.org/libs/graph/doc/DFSVisitor.html |
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#class tree_edges_dfs_visitor(bgl.dfs_visitor): |
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class dfs_visitor_debug(bgl.dfs_visitor): |
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#class tree_edges_bfs_visitor(bgl.bfs_visitor): |
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|
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def __init__(self, startVertex, endVertex, maxdepth, color_map): |
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|
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print dir(self) |
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|
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#bgl.dfs_visitor.__init__(self) |
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#self.name_map = name_map |
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|
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self.startVertex = startVertex |
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self.endVertex = endVertex |
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|
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# for recognizing path switches |
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self.state = True |
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|
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# for tracking paths |
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self.paths = [] |
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self.current_path = [] |
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|
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# for limiting search depth |
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""" |
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self.color_map = color_map |
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self.maxdepth = maxdepth |
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self.depth = 0 |
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""" |
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|
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self.level = 0 |
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|
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|
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def back_edge(self, e, g): |
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self._touch_edge(e, g, 'back_edge') |
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|
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def forward_or_cross_edge(self, e, g): |
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self._touch_edge(e, g, 'forward_or_cross_edge') |
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|
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def tree_edge(self, e, g): |
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self._touch_edge(e, g, 'tree_edge') |
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|
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def examine_edge(self, e, g): |
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self._touch_edge(e, g, 'examine_edge') |
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|
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def _touch_edge(self, e, g, label=''): |
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|
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(u, v) = (g.source(e), g.target(e)) |
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|
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# increase current search depth (level) |
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""" |
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self.depth += 1 |
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|
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# check if maximum depth reached |
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if self.depth == self.maxdepth: |
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# color all succeeding vertices to black (mark as "already visited") |
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# BUG!!! marks too many nodes |
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for child_edge in g.out_edges(v): |
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end_vertex = g.target(child_edge) |
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#self.color_map[end_vertex] = bgl.Color(bgl.Color.gray) |
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""" |
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|
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name_map = g.vertex_properties['node_id'] |
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|
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if label: |
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print "%s:\t" % label, |
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#print "edge ", |
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print name_map[u], |
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print " -> ", |
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print name_map[v] |
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|
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#self.state = True |
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|
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if u == self.startVertex: |
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print "starting" |
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self.current_path = [] |
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|
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# skip circular references |
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if v != self.startVertex: |
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self.current_path.append(e) |
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|
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if v == self.endVertex and self.current_path: |
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print "found:" |
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print self.current_path |
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self.paths.append(self.current_path) |
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self.current_path = [] |
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|
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|
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def _touch_vertex(self, v, g, label=''): |
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name_map = g.vertex_properties['node_id'] |
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id = name_map[v] |
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print '%s:\t%s' % (label, id) |
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|
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|
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def start_vertex(self, v, g): |
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self._touch_vertex(v, g, 'start_vertex') |
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|
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def discover_vertex(self, v, g): |
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self._touch_vertex(v, g, 'discover_vertex') |
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|
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def initialize_vertex(self, v, g): |
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self._touch_vertex(v, g, 'initialize_vertex') |
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|
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def examine_vertex(self, v, g): |
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self._touch_vertex(v, g, 'examine_vertex') |
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|
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def finish_vertex(self, v, g): |
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self._touch_vertex(v, g, 'finish_vertex') |
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|
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|
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""" |
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def start_vertex(self, v, g): |
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self._seperator('start_vertex') |
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#pass |
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#print 'sssss' |
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|
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def discover_vertex(self, v, g): |
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#print '>>>' |
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self._seperator('discover_vertex') |
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#pass |
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|
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def initialize_vertex(self, v, g): |
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#print '>>>' |
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self._seperator('initialize_vertex') |
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|
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def examine_vertex(self, v, g): |
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self._seperator('examine_vertex') |
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|
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def finish_vertex(self, v, g): |
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#print '<<<' |
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if self.current_path: |
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self.paths.append(self.current_path) |
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self.current_path = [] |
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self.depth = 0 |
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self._seperator('finish_vertex') |
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""" |
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|
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def _seperator(self, label = 'unknown'): |
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if 1 or self.state: |
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print '-' * 21, label |
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self.state = False |
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|
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|
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class tree_edges_dfs_visitor(bgl.dfs_visitor): |
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|
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def __init__(self, startVertex, endVertex, maxdepth, color_map): |
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|
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#print dir(self) |
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|
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#bgl.dfs_visitor.__init__(self) |
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#self.name_map = name_map |
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|
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self.startVertex = startVertex |
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self.endVertex = endVertex |
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|
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# for recognizing path switches |
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self.state = True |
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|
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# for tracking paths |
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self.paths = [] |
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self.current_path = [] |
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|
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# for limiting search depth |
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""" |
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self.color_map = color_map |
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self.maxdepth = maxdepth |
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self.depth = 0 |
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""" |
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|
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self.level = 0 |
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|
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def tree_edge(self, e, g): |
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self._touch_edge(e, g, 'tree_edge') |
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|
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def forward_or_cross_edge(self, e, g): |
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#self._touch_edge(e, g, 'forward_or_cross_edge') |
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self.find_new_variations_from_source(e, g) |
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self.find_new_variations_to_target(e, g) |
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|
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|
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def find_new_variations_from_source(self, e, g): |
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# find additional solutions as parts of already established ones (e.g. shortcuts) |
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localEndVertex = g.target(e) |
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path_additional = [] |
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for path in self.paths: |
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found = False |
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for edge in path: |
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if found: |
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path_additional.append(edge) |
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else: |
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if g.source(edge) == localEndVertex: |
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#print "found2" |
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found = True |
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path_additional.append(e) |
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path_additional.append(edge) |
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|
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#print "find_new_variations_from_source:", path_additional |
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if path_additional: |
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self.paths.append(path_additional) |
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|
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def find_new_variations_to_target(self, e, g): |
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# find additional solutions as parts of already established ones (e.g. shortcuts) |
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localStartVertex = g.source(e) |
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localEndVertex = g.target(e) |
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|
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#return |
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|
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#if not (self.endVertex == localEndVertex and self.startVertex != localStartVertex): |
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if not (self.endVertex == localEndVertex): |
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return |
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|
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# find "direct" solution (start- and end-vertices are directly connected) |
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if self.startVertex == localStartVertex: |
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self.paths.append([e]) |
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return |
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|
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#print "check" |
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path_additional = [] |
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for path_iter in self.paths: |
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found = False |
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path = list(path_iter) |
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path.reverse() |
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for edge in path: |
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if found: |
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path_additional.insert(0, edge) |
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else: |
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if g.target(edge) == localStartVertex: |
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#print "found2" |
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found = True |
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path_additional.append(e) |
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path_additional.insert(0, edge) |
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|
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#print "find_new_variations_to_target:", path_additional |
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if path_additional: |
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self.paths.append(path_additional) |
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|
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def _touch_edge(self, e, g, label=''): |
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|
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(u, v) = (g.source(e), g.target(e)) |
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|
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# increase current search depth (level) |
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""" |
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self.depth += 1 |
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|
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# check if maximum depth reached |
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if self.depth == self.maxdepth: |
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# color all succeeding vertices to black (mark as "already visited") |
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# BUG!!! marks too many nodes |
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for child_edge in g.out_edges(v): |
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end_vertex = g.target(child_edge) |
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#self.color_map[end_vertex] = bgl.Color(bgl.Color.gray) |
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""" |
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|
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name_map = g.vertex_properties['node_id'] |
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|
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if DEBUG: |
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if label: |
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print "%s:\t" % label, |
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#print "edge ", |
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print name_map[u], |
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print " -> ", |
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print name_map[v] |
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|
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#self.state = True |
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|
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if u == self.startVertex: |
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#print "starting" |
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self.current_path = [] |
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|
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# skip circular references |
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if v != self.startVertex: |
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self.current_path.append(e) |
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|
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# finish current path if target found |
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if v == self.endVertex and self.current_path: |
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#print "found:" |
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#print self.current_path |
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self.paths.append(self.current_path) |
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self.current_path = [] |
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|
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|
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def build_fixed_graph(): |
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|
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graph = bgl.Graph() |
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index = {} |
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|
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# doesn't this work? see http://www.nabble.com/-Graph--Getting-PageRank-to-work-in-BGL-Python-td14207115.html |
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#graph.add_vertex_property_map(name='my_name', type='float') |
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|
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# 'write_graphviz' requires property 'node_id' on vertices |
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# see http://lists.boost.org/boost-users/2006/06/19877.php |
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vmap = graph.vertex_property_map('string') |
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graph.vertex_properties['node_id'] = vmap |
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|
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|
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v1 = graph.add_vertex() |
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vmap[v1] = '1' |
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index['1'] = v1 |
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|
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v2 = graph.add_vertex() |
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vmap[v2] = '2' |
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index['2'] = v2 |
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|
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v3 = graph.add_vertex() |
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vmap[v3] = '3' |
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index['3'] = v3 |
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|
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v4 = graph.add_vertex() |
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vmap[v4] = '4' |
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index['4'] = v4 |
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|
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e1 = graph.add_edge(v1, v2) |
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e2 = graph.add_edge(v1, v3) |
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e3 = graph.add_edge(v3, v4) |
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|
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e4 = graph.add_edge(v1, v4) |
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e5 = graph.add_edge(v2, v3) |
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e6 = graph.add_edge(v2, v4) |
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|
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""" |
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for vertex in graph.vertices: |
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#print vertex.id, vertex |
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print vmap[vertex], vertex |
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#print vertex.__getattribute__('id') |
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#print vertex['id'] |
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#print vertex.get('id') |
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#print |
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""" |
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|
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graph.write_graphviz('friends.dot') |
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|
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return (graph, index) |
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|
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|
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def build_random_graph(): |
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|
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graph = bgl.Graph() |
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index = {} |
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|
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vmap = graph.vertex_property_map('string') |
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graph.vertex_properties['node_id'] = vmap |
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|
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count = 0 |
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for parent_id in range(1, RANDOM_MAX_NODES + 1): |
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count += 1 |
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if count % 100 == 0: |
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sys.stderr.write('.') |
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|
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parent_id_str = str(parent_id) |
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v1New = False |
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if not index.has_key(parent_id_str): |
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#print "adding v1:", parent_id_str |
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myVertex1 = graph.add_vertex() |
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vmap[myVertex1] = parent_id_str |
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index[parent_id_str] = myVertex1 |
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v1New = True |
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|
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|
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count = 0 |
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#for j in range(1, random.randint(1, RANDOM_MAX_CHILDREN_PER_NODE)): |
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for j in range(1, RANDOM_MAX_CHILDREN_PER_NODE): |
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|
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count += 1 |
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if count % 100 == 0: |
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sys.stderr.write('.') |
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|
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parent_id_str = random.choice(index.keys()) |
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|
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child_id_str = parent_id_str |
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while child_id_str == parent_id_str: |
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child_id_str = random.choice(index.keys()) |
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#print child_id_str |
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|
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myVertex1 = index[parent_id_str] |
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myVertex2 = index[child_id_str] |
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|
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graph.add_edge(myVertex1, myVertex2) |
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|
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sys.stderr.write("\n") |
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|
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return (graph, index) |
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|
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|
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def dump_track(graph, track): |
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track_ids = [] |
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for node in track: |
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node_id = graph.vertex_properties['node_id'][node] |
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track_ids.append(node_id) |
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|
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print ' -> '.join(track_ids) |
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|
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def dump_edges(g, edges): |
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name_map = g.vertex_properties['node_id'] |
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for e in edges: |
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(u, v) = (g.source(e), g.target(e)) |
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print "edge ", |
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print name_map[u], |
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print " -> ", |
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print name_map[v] |
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|
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def find_path_solutions(source, target, graph, paths): |
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|
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print |
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print "=" * 42 |
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print "find_path_solutions" |
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print "=" * 42 |
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|
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#print visitor.paths |
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#(u, v) = (g.source(e), g.target(e)) |
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for path in paths: |
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startVertex = graph.source(path[0]) |
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|
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track = [] |
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track.append(startVertex) |
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|
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for edge in path: |
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endVertex = graph.target(edge) |
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track.append(endVertex) |
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if source == startVertex and target == endVertex: |
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#print "found:", track |
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dump_track(graph, track) |
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|
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def dump_graph(graph): |
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for edge in graph.edges: |
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(u, v) = (graph.source(edge), graph.target(edge)) |
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startIndex = graph.vertex_properties['node_id'][u] |
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endIndex = graph.vertex_properties['node_id'][v] |
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print "%s -> %s" % (startIndex, endIndex) |
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|
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def dump_edges_vertices(graph, edge_list): |
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startVertex = graph.source(edge_list[0]) |
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|
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track = [] |
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track.append(startVertex) |
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|
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for edge in edge_list: |
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endVertex = graph.target(edge) |
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track.append(endVertex) |
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dump_track(graph, track) |
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|
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def print_path_solutions(graph, paths): |
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for path in paths: |
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if DEBUG: |
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print '-' * 21 |
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dump_edges(graph, path) |
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dump_edges_vertices(graph, path) |
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|
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|
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|
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def main(): |
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|
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# Load a graph from the GraphViz file 'mst.dot' |
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#graph = bgl.Graph.read_graphviz('mst.dot') |
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|
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# 1. fixed graph with fixed required solution |
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(graph, index) = build_fixed_graph() |
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startIndex = '1' |
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endIndex = '4' |
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|
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# 2. random graph with according solution |
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#(graph, index) = build_random_graph() |
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#startIndex = random.choice(index.keys()) |
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#endIndex = random.choice(index.keys()) |
527 |
|
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print '-' * 42 |
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print "complete graph:" |
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dump_graph(graph) |
531 |
print '-' * 42 |
532 |
|
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# Compute all paths rooted from each vertex |
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#mst_edges = bgl.kruskal_minimum_spanning_tree(graph, weight) |
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#bgl.depth_first_search(graph, root_vertex = None, visitor = None, color_map = None) |
536 |
|
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""" |
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for root in graph.vertices: |
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print |
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print '=' * 42 |
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print 'Paths originating from node %s' % graph.vertex_properties['node_id'][root] |
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#cmap = graph.vertex_property_map('color') |
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cmap = None |
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visitor = tree_edges_dfs_visitor(3, graph.vertex_properties['node_id'], cmap) |
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#visitor = tree_edges_bfs_visitor(3, graph.vertex_properties['node_id'], cmap) |
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bgl.depth_first_search(graph, root_vertex = root, visitor = visitor, color_map = None) |
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#bgl.breadth_first_search(graph, root_vertex = root, visitor = visitor, color_map = None) |
548 |
#find_path_solutions(index['1'], index['4'], graph, visitor.paths) |
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#sys.exit(0) |
550 |
""" |
551 |
|
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print "Trying to find solution for: %s -> %s" % (startIndex, endIndex) |
553 |
|
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startVertex = index[startIndex] |
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endVertex = index[endIndex] |
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|
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def doCompute(): |
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cmap = graph.vertex_property_map('color') |
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visitor = tree_edges_dfs_visitor(startVertex, endVertex, MAX_SEARCH_DEPTH, cmap) |
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bgl.depth_first_search(graph, root_vertex = startVertex, visitor = visitor, color_map = None) |
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#bgl.depth_first_visit(graph, root_vertex = startVertex, visitor = visitor, color_map = cmap) |
562 |
#find_path_solutions(startVertex, endVertex, graph, visitor.paths) |
563 |
print '-' * 42 |
564 |
print "solution(s):" |
565 |
print_path_solutions(graph, visitor.paths) |
566 |
|
567 |
if ENABLE_PROFILING: |
568 |
global paths |
569 |
paths = [] |
570 |
p = Profile() |
571 |
p.runcall(doCompute) |
572 |
p.print_stats() |
573 |
else: |
574 |
paths = doCompute() |
575 |
|
576 |
|
577 |
# STOP HERE |
578 |
sys.exit(0) |
579 |
|
580 |
|
581 |
|
582 |
|
583 |
|
584 |
# Compute the weight of the minimum spanning tree |
585 |
#print 'MST weight =',sum([weight[e] for e in mst_edges]) |
586 |
|
587 |
# Put the weights into the label. Make MST edges solid while all other |
588 |
# edges remain dashed. |
589 |
label = graph.edge_property_map('string') |
590 |
style = graph.edge_property_map('string') |
591 |
for e in graph.edges: |
592 |
label[e] = str(weight[e]) |
593 |
if e in mst_edges: |
594 |
style[e] = 'solid' |
595 |
else: |
596 |
style[e] = 'dashed' |
597 |
|
598 |
# Associate the label and style property maps with the graph for output |
599 |
graph.edge_properties['label'] = label |
600 |
graph.edge_properties['style'] = style |
601 |
|
602 |
# Write out the graph in GraphViz DOT format |
603 |
graph.write_graphviz('friends_path_2to3.dot') |
604 |
|
605 |
|
606 |
if __name__ == '__main__': |
607 |
main() |