Hi, I have some computations that I used to run without problems in Sage 4.2 but they do not work anymore in Sage 4.4. I believe that I have problems when I use something different from 0,1,2,.... for the name of the vertices of a DiGraph.
I get the same error in my laptop using the version for Ubuntu 64 bits and in a server that compiled Sage. Best, Diego Some toy examples that work in Sage 4.2 but not in Sage 4.4: ---------------------------------------------------------------------- | Sage Version 4.2, Release Date: 2009-10-24 | | Type notebook() for the GUI, and license() for information. | ---------------------------------------------------------------------- sage: G=DiGraph(weighted=True) sage: G.add_edge(0,1,5) sage: G.add_edge(1,2,2) sage: G.vertices() [0, 1, 2] sage: G.shortest_path_length(0,2,by_weight=True) 7 sage: G.shortest_path_length(G.vertices()[0],G.vertices() [2],by_weight=True) 7 sage: sage: G=DiGraph(weighted=True) sage: G.add_edge((0,0),(1,0),5) sage: G.add_edge((1,0),(2,0),2) sage: G.vertices() [(0, 0), (1, 0), (2, 0)] sage: G.shortest_path_length((0, 0),(2, 0),by_weight=True) 7 sage: G.shortest_path_length(G.vertices()[0],G.vertices() [2],by_weight=True) 7 But in Sage 4.4: (it does not even work when I use G.vertices()[0] and G.vertices()[2] ---------------------------------------------------------------------- | Sage Version 4.4, Release Date: 2010-04-24 | | Type notebook() for the GUI, and license() for information. | ---------------------------------------------------------------------- sage: G=DiGraph(weighted=True) sage: G.add_edge(0,1,5) sage: G.add_edge(1,2,2) sage: G.vertices() [0, 1, 2] sage: G.shortest_path_length(0,2,by_weight=True) 7 sage: G.shortest_path_length(G.vertices()[0],G.vertices() [2],by_weight=True) 7 sage: sage: G=DiGraph(weighted=True) sage: G.add_edge((0,0),(1,0),5) sage: G.add_edge((1,0),(2,0),2) sage: G.vertices() [(0, 0), (1, 0), (2, 0)] sage: G.shortest_path_length((0, 0),(2, 0),by_weight=True) --------------------------------------------------------------------------- RuntimeError Traceback (most recent call last) /user/diego/<ipython console> in <module>() /usr/local/sage-4.4/local/lib/python2.6/site-packages/sage/graphs/ generic_graph.pyc in shortest_path_length(self, u, v, by_weight, bidirectional, weight_sum) 7699 if weight_sum is None: 7700 weight_sum = by_weight -> 7701 path = self.shortest_path(u, v, by_weight, bidirectional) 7702 length = len(path) - 1 7703 if length == -1: /usr/local/sage-4.4/local/lib/python2.6/site-packages/sage/graphs/ generic_graph.pyc in shortest_path(self, u, v, by_weight, bidirectional) 7631 if bidirectional: 7632 try: -> 7633 L = self._backend.bidirectional_dijkstra(u,v) 7634 except AttributeError: 7635 try: /usr/local/sage-4.4/local/lib/python2.6/site-packages/sage/graphs/base/ c_graph.so in sage.graphs.base.c_graph.CGraphBackend.bidirectional_dijkstra (sage/ graphs/base/c_graph.c:12323)() /usr/local/sage-4.4/local/lib/python2.6/site-packages/sage/graphs/base/ sparse_graph.so in sage.graphs.base.sparse_graph.SparseGraphBackend.get_edge_label (sage/ graphs/base/sparse_graph.c:15511)() RuntimeError: 0 not a vertex of the graph. sage: G.shortest_path_length(G.vertices()[0],G.vertices() [2],by_weight=True) --------------------------------------------------------------------------- RuntimeError Traceback (most recent call last) /user/diego/<ipython console> in <module>() /usr/local/sage-4.4/local/lib/python2.6/site-packages/sage/graphs/ generic_graph.pyc in shortest_path_length(self, u, v, by_weight, bidirectional, weight_sum) 7699 if weight_sum is None: 7700 weight_sum = by_weight -> 7701 path = self.shortest_path(u, v, by_weight, bidirectional) 7702 length = len(path) - 1 7703 if length == -1: /usr/local/sage-4.4/local/lib/python2.6/site-packages/sage/graphs/ generic_graph.pyc in shortest_path(self, u, v, by_weight, bidirectional) 7631 if bidirectional: 7632 try: -> 7633 L = self._backend.bidirectional_dijkstra(u,v) 7634 except AttributeError: 7635 try: /usr/local/sage-4.4/local/lib/python2.6/site-packages/sage/graphs/base/ c_graph.so in sage.graphs.base.c_graph.CGraphBackend.bidirectional_dijkstra (sage/ graphs/base/c_graph.c:12323)() /usr/local/sage-4.4/local/lib/python2.6/site-packages/sage/graphs/base/ sparse_graph.so in sage.graphs.base.sparse_graph.SparseGraphBackend.get_edge_label (sage/ graphs/base/sparse_graph.c:15511)() RuntimeError: 0 not a vertex of the graph. sage: -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
