dplyr - R calculating grouped frequency table with percentage -

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• calculate percentage each time series observations per group in r 2 answers

giving following data.frame, calculate occurance of each variable of var , percentage of these occurence grouping variable group:

group<-c("g1","g2","g1","g2","g3","g3","g1") var<-c("a","b","b","a","b","b","a") d<-data.frame(group,var) 

with table(), nice frequency table, counting occurences of combinations of 2 variables:

d<-as.data.frame(table(d))   group var freq 1    g1      2 2    g2      1 3    g3      0 4    g1   b    1 5    g2   b    1 6    g3   b    2 

now calculate percentage of each variable var group. far i'm splitting data.frame group , calculate percentage seperately g1, g2 , g3 , merging afterwards.

d.g1<-d[d$group=="g1",] d.g1$per<-d.g1$freq/sum(d.g1$freq) d.g1   group var freq       per 1    g1      2 0.6666667 4    g1   b    1 0.3333333 

...

d.merge<-rbind(d.g1,d.g2,d.g3) d.merge  group var freq       per 1    g1      2 0.6666667 4    g1   b    1 0.3333333 2    g2      1 0.5000000 5    g2   b    1 0.5000000 3    g3      0 0.0000000 6    g3   b    2 1.0000000 

is there more elegant solution using example reshape2 package?

with dplyrpackage can do:

require(dplyr)  d <- d %>% group_by(group) %>% mutate(per = freq/sum(freq))