R 데이터프레임 날짜 변경

1 개요

R 데이터프레임 날짜 변경

df <- read.table( header=T, stringsAsFactors=FALSE, text="
day         fruit    ea
2000-06-01  apple    1
2000-06-01  apple    1
2000-06-02  banana   2
2019-06-02  apple    3
2019-06-03  banana   4
")
df$day <- as.Date(df$day)
df
##          day  fruit ea
## 1 2000-06-01  apple  1
## 2 2000-06-01  apple  1
## 3 2000-06-02 banana  2
## 4 2019-06-02  apple  3
## 5 2019-06-03 banana  4

library("lubridate")
year(df[df$day < "2001-01-01",]$day) <- 2018
df
##          day  fruit ea
## 1 2018-06-01  apple  1
## 2 2018-06-01  apple  1
## 3 2018-06-02 banana  2
## 4 2019-06-02  apple  3
## 5 2019-06-03 banana  4

2 같이 보기

• R year()
• R 데이터 전처리

3 참고

• https://stackoverflow.com/questions/27287052/change-the-year-in-a-datetime-object-in-r