I know there must be a one-line data.table
solution for this, probably with dcast
, but I can't figure it out.
I have data like this:
library(data.table)
data1 <- data.table(
id = seq(1:5),
code = c("A","A","B","A","B"),
date = as.Date( c("2021-08-11","2021-01-05","2021-02-18","2021-02-13","2021-12-13" ))
)
data2 <- data.table(
id = seq(1:5),
code = c("B","B","A","B","A"),
date = as.Date( c("2021-08-13","2021-01-05","2021-02-19","2021-02-14","2021-12-13" ))
)
data3 <- rbind(data1, data2)
I simply wish to reshape to a wide format like this
data_want <- data.table(
id = seq(1:5),
code1 = c("A", "A","B","A","B"),
data1 = c("2021-08-11", "2021-01-05","2021-02-18","2021-02-13","2021-12-13"),
code2 = c("B", "B","A","B","A"),
data2 = c("2021-08-13", "2021-01-05","2021-02-19","2021-02-14","2021-12-13")
)
How to do it with dcast
?
You could also make use of rowid
as follows
dcast(data3, id ~ rowid(id), value.var = c("code", "date"))
# id code_1 code_2 date_1 date_2
#1: 1 A B 2021-08-11 2021-08-13
#2: 2 A B 2021-01-05 2021-01-05
#3: 3 B A 2021-02-18 2021-02-19
#4: 4 A B 2021-02-13 2021-02-14
#5: 5 B A 2021-12-13 2021-12-13