R ddply()

1 개요

R ddply()

library(plyr)
df = data.frame(x1=c(0,1,1,1,2,3,3,3),
                x2=c(0,1,1,3,2,3,3,2),
                x3=c(0,1,1,1,2,3,3,2))
ddply(df, .(x1, x2, x3), nrow)
##   x1 x2 x3 V1
## 1  0  0  0  1
## 2  1  1  1  2
## 3  1  3  1  1
## 4  2  2  2  1
## 5  3  2  2  1
## 6  3  3  3  2

2 같이 보기

• R tapply()
• R d_ply()
• R daply()
• R dlply()
• R adply()
• R ldply()
• R mdply()

3 참고

• https://www.rdocumentation.org/packages/plyr/versions/1.8.4/topics/ddply