--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/app/graph/readwrite.py Wed Nov 26 23:56:19 2008 +0000
@@ -0,0 +1,302 @@
+# Copyright (c) 2007-2008 Pedro Matiello <pmatiello@gmail.com>
+#
+# Permission is hereby granted, free of charge, to any person
+# obtaining a copy of this software and associated documentation
+# files (the "Software"), to deal in the Software without
+# restriction, including without limitation the rights to use,
+# copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following
+# conditions:
+
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+# OTHER DEALINGS IN THE SOFTWARE.
+
+
+"""
+Functions for reading and writing graphs.
+
+@sort: read_xml, write_xml, write_dot_graph, write_dot_digraph, write_dot_hypergraph
+"""
+
+
+# Imports
+from xml.dom.minidom import Document, parseString
+
+
+# Values
+colors = ['aquamarine4', 'blue4', 'brown4', 'cornflowerblue', 'cyan4',
+ 'darkgreen', 'darkorange3', 'darkorchid4', 'darkseagreen4', 'darkslategray',
+ 'deeppink4', 'deepskyblue4', 'firebrick3', 'hotpink3', 'indianred3',
+ 'indigo', 'lightblue4', 'lightseagreen', 'lightskyblue4', 'magenta4',
+ 'maroon', 'palevioletred3', 'steelblue', 'violetred3']
+
+
+# XML
+
+def write_xml(graph):
+ """
+ Return a string specifying the given graph as a XML document.
+
+ @type graph: graph
+ @param graph: Graph.
+
+ @rtype: string
+ @return: String specifying the graph as a XML document.
+ """
+
+ # Document root
+ grxml = Document()
+ grxmlr = grxml.createElement('graph')
+ grxml.appendChild(grxmlr)
+
+ # Each node...
+ for each_node in graph.nodes():
+ node = grxml.createElement('node')
+ node.setAttribute('id',str(each_node))
+ grxmlr.appendChild(node)
+ for each_attr in graph.get_node_attributes(each_node):
+ attr = grxml.createElement('attribute')
+ attr.setAttribute('attr', each_attr[0])
+ attr.setAttribute('value', each_attr[1])
+ node.appendChild(attr)
+
+ # Each edge...
+ for edge_from, edge_to in graph.edges():
+ edge = grxml.createElement('edge')
+ edge.setAttribute('from',str(edge_from))
+ edge.setAttribute('to',str(edge_to))
+ edge.setAttribute('wt',str(graph.get_edge_weight(edge_from, edge_to)))
+ edge.setAttribute('label',str(graph.get_edge_label(edge_from, edge_to)))
+ grxmlr.appendChild(edge)
+ for attr_name, attr_value in graph.get_edge_attributes(edge_from, edge_to):
+ attr = grxml.createElement('attribute')
+ attr.setAttribute('attr', attr_name)
+ attr.setAttribute('value', attr_value)
+ edge.appendChild(attr)
+
+ return grxml.toprettyxml()
+
+
+def write_xml_hypergraph(hypergraph):
+ """
+ Return a string specifying the given hypergraph as a XML document.
+
+ @type hypergraph: hypergraph
+ @param hypergraph: Hypergraph.
+
+ @rtype: string
+ @return: String specifying the graph as a XML document.
+ """
+
+ # Document root
+ grxml = Document()
+ grxmlr = grxml.createElement('hypergraph')
+ grxml.appendChild(grxmlr)
+
+ # Each node...
+ nodes = hypergraph.nodes()
+ hyperedges = hypergraph.get_hyperedges()
+ for each_node in (nodes + hyperedges):
+ if (each_node in nodes):
+ node = grxml.createElement('node')
+ else:
+ node = grxml.createElement('hyperedge')
+ node.setAttribute('id',str(each_node))
+ grxmlr.appendChild(node)
+
+ # and its outgoing edge
+ for each_edge in hypergraph.get_links(each_node):
+ edge = grxml.createElement('link')
+ edge.setAttribute('to',str(each_edge))
+ node.appendChild(edge)
+
+ return grxml.toprettyxml()
+
+
+def read_xml(graph, string):
+ """
+ Read a graph from a XML document. Nodes and edges specified in the input will be added to the current graph.
+
+ @type graph: graph
+ @param graph: Graph
+
+ @type string: string
+ @param string: Input string in XML format specifying a graph.
+ """
+ dom = parseString(string)
+
+ # Read nodes...
+ for each_node in dom.getElementsByTagName("node"):
+ graph.add_node(each_node.getAttribute('id'))
+ for each_attr in each_node.getElementsByTagName("attribute"):
+ graph.add_node_attribute(each_node.getAttribute('id'), (each_attr.getAttribute('attr'),
+ each_attr.getAttribute('value')))
+
+ # Read edges...
+ for each_edge in dom.getElementsByTagName("edge"):
+ graph.add_edge(each_edge.getAttribute('from'), each_edge.getAttribute('to'), \
+ wt=float(each_edge.getAttribute('wt')), label=each_edge.getAttribute('label'))
+ for each_attr in each_edge.getElementsByTagName("attribute"):
+ attr_tuple = (each_attr.getAttribute('attr'), each_attr.getAttribute('value'))
+ if (attr_tuple not in graph.get_edge_attributes(each_edge.getAttribute('from'), \
+ each_edge.getAttribute('to'))):
+ graph.add_edge_attribute(each_edge.getAttribute('from'), \
+ each_edge.getAttribute('to'), attr_tuple)
+
+
+def read_xml_hypergraph(hypergraph, string):
+ """
+ Read a graph from a XML document. Nodes and hyperedges specified in the input will be added to the current graph.
+
+ @type hypergraph: hypergraph
+ @param hypergraph: Hypergraph
+
+ @type string: string
+ @param string: Input string in XML format specifying a graph.
+ """
+ dom = parseString(string)
+ for each_node in dom.getElementsByTagName("node"):
+ hypergraph.add_nodes(each_node.getAttribute('id'))
+ for each_node in dom.getElementsByTagName("hyperedge"):
+ hypergraph.add_hyperedges(each_node.getAttribute('id'))
+ dom = parseString(string)
+ for each_node in dom.getElementsByTagName("node"):
+ for each_edge in each_node.getElementsByTagName("link"):
+ hypergraph.link(each_node.getAttribute('id'), each_edge.getAttribute('to'))
+
+
+# DOT Language
+
+def _dot_node_str(graph, node, wt):
+ line = '\t"%s" [ ' % str(node)
+ attrlist = graph.get_node_attributes(node)
+ for each in attrlist:
+ attr = '%s="%s" ' % (each[0], each[1])
+ line = line + attr
+ line = line + ']\n'
+ return line
+
+
+def _dot_edge_str(graph, u, v, wt):
+ line = '\t"%s" -- "%s" [ ' % (str(u), str(v))
+ attrlist = graph.get_edge_attributes(u, v) + [('label',graph.get_edge_label(u, v))]
+ for each in attrlist:
+ attr = '%s="%s" ' % (each[0], each[1])
+ line = line + attr
+ line = line + ']\n'
+ return line
+
+
+def _dot_arrow_str(graph, u, v, wt):
+ line = '\t"%s" -> "%s" [ ' % (str(u), str(v))
+ attrlist = graph.get_edge_attributes(u, v) + [('label',graph.get_edge_label(u, v))]
+ for each in attrlist:
+ attr = '%s="%s" ' % (each[0], each[1])
+ line = line + attr
+ line = line + ']\n'
+ return line
+
+
+def write_dot_graph(graph, wt):
+ """
+ Return a string specifying the given graph in DOT Language.
+
+ @type graph: graph
+ @param graph: Graph.
+
+ @type wt: boolean
+ @param wt: Whether edges should be labelled with its weight.
+
+ @rtype: string
+ @return: String specifying the graph in DOT Language.
+ """
+ doc = 'graph graphname \n{\n'
+ for node in graph:
+ doc = doc + _dot_node_str(graph, node, wt)
+ for edge in graph[node]:
+ if (node >= edge):
+ doc = doc + _dot_edge_str(graph, node, edge, wt)
+ doc = doc + '}'
+ return doc
+
+
+def write_dot_digraph(graph, wt):
+ """
+ Return a string specifying the given digraph in DOT Language.
+
+ @type graph: graph
+ @param graph: Graph.
+
+ @type wt: boolean
+ @param wt: Whether arrows should be labelled with its weight.
+
+ @rtype: string
+ @return: String specifying the graph in DOT Language.
+ """
+ doc = 'digraph graphname \n{\n'
+ for node in graph:
+ doc = doc + _dot_node_str(graph, node, wt)
+ for edge in graph[node]:
+ doc = doc + _dot_arrow_str(graph, node, edge, wt)
+ doc = doc + '}'
+ return doc
+
+
+def write_dot_hypergraph(hypergraph, coloured=False):
+ """
+ Return a string specifying the given hypergraph in DOT Language.
+
+ @type hypergraph: hypergraph
+ @param hypergraph: Hypergraph.
+
+ @type coloured: boolean
+ @param coloured: Whether hyperedges should be coloured.
+
+ @rtype: string
+ @return: String specifying the hypergraph in DOT Language.
+ """
+ # Start document
+ doc = ""
+ doc = doc + "graph graphname" + "\n{\n"
+ colortable = {}
+ colorcount = 0
+
+
+ # Add hyperedges
+ color = ''
+ for each_hyperedge in hypergraph.hyperedges():
+ colortable[each_hyperedge] = colors[colorcount % len(colors)]
+ colorcount = colorcount + 1
+ if (coloured):
+ color = " color=%s" % colortable[each_hyperedge]
+ vars = {
+ 'hyperedge' : str(each_hyperedge),
+ 'color' : color
+ }
+ doc = doc + '\t"%(hyperedge)s" [shape=point %(color)s]\n' % vars
+
+ color = "\n"
+ # Add nodes and links
+ for each_node in hypergraph.nodes():
+ doc = doc + "\t\"%s\"\n" % str(each_node)
+ for each_link in hypergraph.links(each_node):
+ if (coloured):
+ color = " [color=%s]\n" % colortable[each_link]
+ linkvars = {
+ 'node' : str(each_node),
+ 'hyperedge' : str(each_link)
+ }
+ doc = doc + '\t %(node)s -- %(hyperedge)s' % linkvars + color
+
+ doc = doc + "}"
+ return doc