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rigraph

R: Making a network graph using comma separated values in a column

Is there a way I can make a network graph like this, for instance:

Colour               IDs
Red                  12,14,15
Green                17,20,25
Blue                 20,39,46

where (12,14,15) will be a network, (17,20,25) will be a network, and (20,39,46) will also be a network, but the 20 from Green and Blue will be connected.

Is there a function for this, or do I have to manually split the comma separated values?

Thank you!

Solution

  • Using tidyverse and igraph libraries:

    library(tidyverse)
library(igraph)

dat %>% 
  separate_rows(IDs) %>% 
  group_by(Colour) %>% 
  do(data.frame(t(combn(.$IDs, 2)))) %>% 
  select(X1, X2, color = Colour) %>% 
  graph_from_data_frame(directed = F) %>% 
  plot()

    enter image description here

    An alternative when some groups have only one node:

    dat %>% 
  separate_rows(IDs) %>% 
  group_by(Colour) %>% 
  summarise(new = ifelse(n() > 1, paste(combn(IDs, 2), collapse = "-"), as.character(IDs))) %>% 
  separate_rows(new, sep = "(?:[^-]*(?:-[^-]*){1})\\K-") %>% 
  separate(new, into = c("X1", "X2")) %>% 
  select(X1, X2, color = Colour) %>% 
  graph_from_data_frame(directed = F) %>% 
  plot()