# Subset of edges with a different color

I want to color a subset of the edges of my graph with a different color. My graph currently has a large number of edges, so the following is just a toy example

s = {1->2,1->3}
g = {1->2, 1->3,3->4,4->1}
GraphPlot[g,VertexLabeling->True]


Here s is a subset of g I would like to tell GraphPlot to plot the edges in s with a different color, and make the edges of s directed.

How to do this?

EDIT:

The closest I have coming after looking at some answer to another question on this site is

s = {{1,2},{1,3}}
g = {1->2, 1->3,3->4,4->1}
GraphPlot[g,VertexLabeling->True,EdgeRenderingFunction -> (If[
Intersection[s, {#2}] != {}, {Red ,Arrow[#1, .1]},
{Blue,Arrow[#1, .1]}] &)]


However, since I want the complement of the set s in g to be represented as blue segment (and not an arrow) I am not sure what I should write in place of Arrow inside {Blue,Arrow[#1, .1]} above.

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THere are several examples in the documentation for VertexRenderingFunction. The help file will show you how to apply it. –  bill s Jun 5 '13 at 19:41
Something like HighlightGraph[Graph[{1 -> 2, 1 -> 3, 3 -> 4, 4 -> 1}], {1 -> 2, 1 -> 3}]? –  Guess who it is. Jun 5 '13 at 19:43
@0x4A4D Yes almost, like that.However, please see edit. –  smilingbuddha Jun 5 '13 at 19:51
s = {{1, 2}, {1, 3}} g = {1 -> 2, 1 -> 3, 3 -> 4, 4 -> 1} GraphPlot[g, VertexLabeling -> True, EdgeRenderingFunction -> (If[ Intersection[s, {#2}] != {}, {Red, Line[#1]}, {Blue, Arrow[#1, .1]}] &)] –  belisarius Jun 5 '13 at 21:59
@Anon I posted an answer, let's see if the community thinks it has some value –  belisarius Jan 13 '14 at 0:23

s = {{1, 2}, {1, 3}};