r - Convert integer as "20160119" to different columns of "day" "year" "month"

Question

How can I convert a column of integers as dates:

       DATE PRCP
1: 19490101   25
2: 19490102    5
3: 19490118   18
4: 19490119  386
5: 19490202   38

to a table like this:

days   month   years   PRCP

Answer 1

We can use extract

library(tidyr)
extract(df, DATE, into=c('YEAR', 'MONTH', 'DAY'), 
         '(.{4})(.{2})(.{2})', remove=FALSE)
#       DATE YEAR MONTH DAY PRCP
#1 19490101 1949    01  01   25
#2 19490102 1949    01  02    5
#3 19490118 1949    01  18   18
#4 19490119 1949    01  19  386
#5 19490202 1949    02  02   38