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I have very basic issue with igraph (in R): renaming of the node ids.

For example, I have following graph in form of edgelist.

10,12
10,14
12,14
12,15
14,15
12,17
17,34
17,100
100,34

I want to calculate local clustering coefficient for each node. First I have read the edgelist in object g using readcsv. Then, I used the following command to dump the local CC for each node. 

write.csv(transitivity(g,type="local"),file="DumpLocalCC.csv")

Now the problem is, igraph changes the node IDs starting from 1 and I get following output

"","x"
"1",NA
"2",0.333333333333333
"3",0.333333333333333
"4",0.333333333333333
"5",1
"6",1
"7",1

Now how can I resolute which node id is what ? That is if 7 in the output file points to 100 or 34 ? Is there anyway, we can force igraph to dump actual nodeids like 10, 34, 100 etc and their respective Local CC ?

I was googling and found people suggested "V(g)$name <- as.character(V(g))" for preserving the nodeids. I tried however, I think I am not using it correctly. Also, since the data is large, I would not like to change the nodeids manually to make them sequential from 1 .... myself.

P.s: Here I noticed a similar question has been asked. It has been suggested to "assign these numbers as vertex names". How to do that ? Can someone exemplify it please ?

Another similar question like this (I understand its the similar question), where it was suggested to open an issue. I am not sure if this has been resolved ?

Thanks in advance.

Community
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raj
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  • It would be easier to help you if you provided a proper [reproducible example](http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example) with code we can copy/paste into R to test. Show exactly how you are creating the graph object. – MrFlick May 17 '17 at 18:24
  • Edge list has been provided. I am using following code to read it DF <- read.csv("PATH OF EDGELIST.csv") g <- graph.DF(advice_data_frame) and above I provided example of how I am calculating Clustering coefficient (transitivity) and dumping it in the file – raj May 17 '17 at 18:34

1 Answers1

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You just need to combine the stats with the node names when you write the table. For example

DF <- read.csv(text="10,12
    10,14
    12,14
    12,15
    14,15
    12,17
    17,34
    17,100
    100,34", header=FALSE)
g <- graph.data.frame(DF)
outdata <- data.frame(node=names(V(g)), trans=transitivity(g, type="local"))
write.csv(outdata, file="DumpLocalCC.csv")
MrFlick
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  • May I know what if I have calculated the 'edge betweennness' using centrality_auto(), and I need the node IDs instead of 1,2, 3...? V(g) gives node names for node centrality, but for edgelists, the node names in the edgelist cannot be joined by the above method. – Grace Oct 23 '21 at 12:45