[BioC] removeEdge: strange error

[Dan Bebber]

Hello,

I am having problems removing multiple edges from graphs.
When I try to remove many edges, I get 'Error: subscript out of bounds', 
despite the fact that there are enough edges in the graph.
An example follows:

library(graph) #load library
From<-c(1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, #these 
are the 'from' nodes
2, 5, 5, 8, 8, 8, 8, 8, 11, 11, 12, 12, 12, 14, 14, 16, 16, 20,
20, 23, 23, 24, 24, 25, 25, 29, 29, 32, 32, 32, 32, 38, 38, 41,
41, 41, 43, 43, 54, 54, 59, 59, 60, 68, 68, 69, 72, 82, 83, 88,
88, 88, 88, 89, 89, 90, 90, 96, 97, 98, 98, 98)
To<-c(2, 5, 8, 11, 12, 14, 16, 20, 23, 37, 38, 54, 57, 68, 72, 81, #these 
are the 'to' nodes
86, 87, 97, 88, 100, 32, 102, 38, 41, 49, 51, 53, 58, 59, 60,
63, 67, 71, 72, 75, 76, 84, 85, 24, 29, 25, 28, 26, 27, 30, 31,
33, 34, 35, 36, 40, 41, 42, 43, 47, 44, 45, 55, 56, 60, 62, 61,
70, 71, 71, 73, 84, 84, 89, 90, 93, 94, 97, 141, 95, 141, 141,
98, 99, 141, 158)
FT<-matrix(c(From,To),nc=2) #create a 'from-to' matrix
g<-ftM2graphNEL(FT,edgemode="undirected") #generate the graph
g
gr<-removeEdge(from=as.character(From[1:2]),to=as.character(To[1:2]),g) 
#this works, and removes 2 edges
gr
gr<-removeEdge(from=as.character(From[1:20]),to=as.character(To[1:20]),g) 
#this gives 'Error: subscript out of bounds'


Thanks,
Dan Bebber
________________________
Dr. Daniel P. Bebber
Department of Plant Sciences
University of Oxford
South Parks Road
Oxford OX1 3RB
UK
Tel. 01865 275060