How to transform a key/value string into separate columns?

Question

I\'ve got a data.frame with key/value string column containing information about features and their values for a set of users. Something like this:

Answer 1

We can use cSplit to do this in a cleaner way. Convert the data to 'long' format by splitting at ,, then do the split at : and dcast from 'long' to 'wide'

library(splitstackshape)
library(data.table)
dcast(cSplit(cSplit(data, "str", ",", "long"), "str", ":"), 
                    id+statid~str_1, value.var="str_2", fill = 0)
#   id statid 7 a b  c
#1:  1  s003e 2 1 0  0
#2:  2  s093u 0 1 0  4
#3:  3  s085t 0 3 5 33