split - In R: get multiple rows by splitting a column using tidyr and reshape2 -

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• split comma-separated column separate rows 4 answers

what simpel way using tidyr or reshape2 turn data:

data <- data.frame(       a=c(1,2,3),       b=c("b,g","g","b,g,q")) 

into (e.g. make row each comma separated value in variable b):

  b 1 1 b 2 1 g 3 2 g 4 3 b 5 3 g 6 3 q 

try

library(splitstackshape)  csplit(data, 'b', ',', 'long') 

or using base r

lst <- setnames(strsplit(as.character(data$b), ','), data$a) stack(lst) 

or

library(tidyr)  unnest(lst,a)