我的输出与代码不符，我无法确定哪里出错了

Question

我是 R 的新手，我想使用“case when”语句为我的 table 创建一个名为 Reporting Month 的新列（格式：日期），条件是使用一个名为 Period 的列（格式：字符）执行的代码但日期的输出范围仅为 31/01/2020 到 31/12/2020，2019 年或 2021 年没有，有人可以帮忙吗？如果有更简洁的方法，我也非常感谢您的建议！非常感谢！！

dt <- dt %>%  mutate(
  Reporting_Month = case_when(
    Period == 'ZZZ-MARCH-2019' ~ as.Date("31/03/2019", format("%d/%m/%y")),
    Period == 'ZZZ-APRIL-2019' ~ as.Date("30/04/2019", format("%d/%m/%y")),
    Period == 'ZZZ-MAY-2019' ~ as.Date("31/05/2019", format("%d/%m/%y")),
    Period == 'ZZZ-JUNE-2019' ~ as.Date("30/06/2019", format("%d/%m/%y")),
    Period == 'ZZZ-JULY-2019' ~ as.Date("31/07/2019", format("%d/%m/%y")),
    Period == 'ZZZ-AUGUST-2019' ~ as.Date("31/08/2019", format("%d/%m/%y")),
    Period == 'ZZZ-SEPTEMBER-2019' ~ as.Date("30/09/2019", format("%d/%m/%y")),
    Period == 'ZZZ-OCTOBER-2019' ~ as.Date("31/10/2019", format("%d/%m/%y")),
    Period == 'ZZZ-NOVEMBER-2019' ~ as.Date("30/11/2019", format("%d/%m/%y")),
    Period == 'ZZZ-DECEMBER-2019' ~ as.Date("31/12/2019", format("%d/%m/%y")),
    Period == 'ZZZ-JANUARY-2020' ~ as.Date("31/01/2020", format("%d/%m/%y")),
    Period == 'ZZZ-FEBRUARY-2020' ~ as.Date("29/02/2020", format("%d/%m/%y")),
    Period == 'ZZZ-MARCH-2020' ~ as.Date("31/03/2020", format("%d/%m/%y")),
    Period == 'ZZZ-APRIL-2020' ~ as.Date("30/04/2020", format("%d/%m/%y")),
    Period == 'ZZZ-MAY-2020' ~ as.Date("31/05/2020", format("%d/%m/%y")),
    Period == 'ZZZ-JUNE-2020' ~ as.Date("30/06/2020", format("%d/%m/%y")),
    Period == 'ZZZ-JULY-2020' ~ as.Date("31/07/2020", format("%d/%m/%y")),
    Period == 'ZZZ-AUGUST-2020' ~ as.Date("31/08/2020", format("%d/%m/%y")),
    Period == 'ZZZ-SEPTEMBER-2020' ~ as.Date("30/09/2020", format("%d/%m/%y")),
    Period == 'ZZZ-OCTOBER-2020' ~ as.Date("31/10/2020", format("%d/%m/%y")),
    Period == 'ZZZ-NOVEMBER-2020' ~ as.Date("30/11/2020", format("%d/%m/%y")),
    Period == 'ZZZ-DECEMBER-2020' ~ as.Date("31/12/2020", format("%d/%m/%y")),
    Period == 'ZZZ-JANUARY-2021' ~ as.Date("31/01/2021", format("%d/%m/%y")),
    TRUE                      ~  as.Date("31/01/2000")
  )
)

Answer 1

library(lubridate) 

dt %>%  mutate(
  Reporting_Month = ceiling_date(dmy(str_replace(Period, 'ZZZ', '01')), unit = 'month') - days(1))
             Period Reporting_Month
1    ZZZ-APRIL-2019      2019-04-30
2  ZZZ-OCTOBER-2019      2019-10-31
3     ZZZ-JULY-2020      2020-07-31
4 ZZZ-DECEMBER-2021      2021-12-31
5  ZZZ-JANUARY-2021      2021-01-31

用一个虚拟的例子

dt
> dt
             Period
1    ZZZ-APRIL-2019
2  ZZZ-OCTOBER-2019
3     ZZZ-JULY-2020
4 ZZZ-DECEMBER-2021
5  ZZZ-JANUARY-2021

Answer 2

您可以将 Period 更改为 yearmon class，然后将日期更改为 frac = 1 以获得该月的最后一天。

library(dplyr)
library(zoo)

dt %>% mutate(Reporting_Month = as.Date(as.yearmon(Period,'ZZZ-%b-%Y'),frac = 1))

#             Period Reporting_Month
#1    ZZZ-MARCH-2019      2019-03-31
#2     ZZZ-JUNE-2019      2019-06-30
#3  ZZZ-OCTOBER-2019      2019-10-31
#4 ZZZ-DECEMBER-2019      2019-12-31

数据

dt <- data.frame(Period = c('ZZZ-MARCH-2019', 'ZZZ-JUNE-2019', 
                            'ZZZ-OCTOBER-2019', 'ZZZ-DECEMBER-2019'))

我的输出与代码不符，我无法确定哪里出错了

My output is not as per the code and I cannot identify where have I gone wrong

r

dplyr

case-when