EdgeRenderingFunction to produce edge labels in GraphPlot

*To*: mathgroup at smc.vnet.net*Subject*: [mg87549] EdgeRenderingFunction to produce edge labels in GraphPlot*From*: Murray Eisenberg <murray at math.umass.edu>*Date*: Sat, 12 Apr 2008 07:03:16 -0400 (EDT)*Organization*: Mathematics & Statistics, Univ. of Mass./Amherst*Reply-to*: murray at math.umass.edu

I'm having trouble fathoming from the documentation how EdgeRenderingFunction works. In a display produced by GraphPlot, applied to a graph that's a Graph object created with Combinatorica, I want to be able to put distinct labels on the edges. For example, take something very simple: g = Cycle[3]; I'd like to put labels "a", "b", "c" on the three {1,2}, {2,3}, {3,1}, respectively. Here's what I tried finally: labels = Characters["abc"]; edgeLabelFunction[{u_, v_}] := labels[[First@Flatten@Position[Edges[Cycle[3]], {u, v}]]] offset={0.05,0.05}; (* to move labels away from edges *) GraphPlot[g, Method -> None, EdgeRenderingFunction -> ({ Line[#1], Inset[edgeLabelFunction[#2], Mean[#1] + offset] ]} &) ] This does not work. How, exactly, do I index into the list of edges... Edges[g] {{1,2},{2,3},{1,3}} .. so as to select the labels. From the reference page on EdgeRenderingFunction, it seems to me that argument #2 is supposed to be the length 2 list {u,v} of vertices with which the edge is incident. -- Murray Eisenberg murray at math.umass.edu Mathematics & Statistics Dept. Lederle Graduate Research Tower phone 413 549-1020 (H) University of Massachusetts 413 545-2859 (W) 710 North Pleasant Street fax 413 545-1801 Amherst, MA 01003-9305

**Follow-Ups**:**Re: EdgeRenderingFunction to produce edge labels in GraphPlot***From:*Carl Woll <carlw@wolfram.com>