using graph.adjacency() in R

Question

I have a sample code in R as follows:

library(igraph)
rm(list=ls())
dat=read.csv(file.choose(),header=TRUE,row.names=1,check.names=T) # read .csv file
m=as.m         


        

Answer 1

Just a small working example below, much clearer than CSV input.

library('igraph');
adjm1<-matrix(sample(0:1,100,replace=TRUE,prob=c(0.9,01)),nc=10); 
g1<-graph.adjacency(adjm1); 
plot(g1)

P.s. ?graph.adjacency has a lot of good examples (remember to run library('igraph')).

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Answer 2

The problem seems to be due to the data-type of the matrix elements. graph.adjacency expects elements of type numeric. Not sure if its a bug.

After you do,

m <- as.matrix(dat)

set its mode to numeric by:

mode(m) <- "numeric"

And then do:

net <- graph.adjacency(m, mode = "undirected", weighted = TRUE, diag = FALSE)
> E(net)$weight
[1]  8  1 10  1 15  1  1  5  7  1