# igraph degree distribution: count elements

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Unfortunately, the degree.distribution() function of the igraph library returns the intensities of the distribution:**0xCAFEBABE**, and kindly contributed to R-bloggers]. (You can report issue about the content on this page here)Want to share your content on R-bloggers? click here if you have a blog, or here if you don't.

> g <- graph.ring(5) > plot(g) > summary(g) IGRAPH U--- 10 10 -- Ring graph attr: name (g/c), mutual (g/x), circular (g/x)

So instead of having the number of elements, the density/intensities value is returned:

> degree.distribution(g) [1] 0 0 1

You can easily verify this in the source code of the function:

> degree.distribution function (graph, cumulative = FALSE, ...) { if (!is.igraph(graph)) { stop("Not a graph object") } cs <- degree(graph, ...) hi <- hist(cs, -1:max(cs), plot = FALSE)$intensities if (!cumulative) { res <- hi } else { res <- rev(cumsum(rev(hi))) } res }

This caused me some minor issues, but the solution was easy. I simply created a new version of the function that is using

*$count*instead of

*$intensities*(BTW $intensities will be deprecated in R 3.0).

count.degree.distribution <- function (graph, cumulative = FALSE, ...) { if (!is.igraph(graph)) { stop("Not a graph object") } cs <- degree(graph, ...) hi <- hist(cs, -1:max(cs), plot = FALSE)$count if (!cumulative) { res <- hi } else { res <- rev(cumsum(rev(hi))) } res }Using it is identical to the original version:

> count.degree.distribution(g) [1] 0 0 10

To

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