[BioC] Package "graph": bug in function addEdge

[Dirk Koschützki]

Hello,

the graph package contains a bug in the function addEdge. If I add a
second edge between vertices s and t, then any existing edge gets
replaced.

The following code shows this effect:

library (graph)
rm (list=ls())

installed.packages ()["graph",]

G1 <- new ("graphNEL", nodes=c ("A", "B", "C", "D"), edgemode="directed")
numNodes (G1)
nodes (G1)

G2 <- addEdge ("C", "D", G1, 1.1)
numEdges (G2)
edges (G2)
edgeWeights (G2)

G3 <- addEdge ("C", "D", G2, 2.2)
numEdges (G3)
edges (G3)
edgeWeights (G3)

G4 <- addEdge ("C", "D", G3, 3.3)
numEdges (G4)
edges (G4)
edgeWeights (G4)


With R 2.2.1 and graph package 1.8.0 G4 contains three edges with the
expected weights and in R 2.4.1 running the current version of the
package G4 only contains the edge with the weight 3.3.

With kind regards,
Dirk