How do I convert 2021-22 to as year 2021-22-CodePudding

The year is in factor type. I want to convert as date. How do I convert it to date?data set image

CodePudding user response：

Suppose you have:

my_df <- data.frame(year = as.factor(c("1983-84", "1984-85")))

You could extract the ending year using:

my_df$year_num = as.numeric(substr(as.character(my_df$year), 1, 4))   1

This takes the year variable which is a factor, converts it to character based on its labels, extracts the first 4 characters (the starting year), converts to number, and adds one. If you want year_num to instead show the starting year, skip that last step.

You could also specify a specific date like the last day of the FY (assuming here June 30th) using:

my_df$FY_end = as.Date(paste0(my_df$year_num, "-06-30"))

Result

     year year_num     FY_end
1 1983-84     1984 1984-06-30
2 1984-85     1985 1985-06-30


> str(my_df)
'data.frame':   2 obs. of  3 variables:
 $ year    : Factor w/ 2 levels "1983-84","1984-85": 1 2
 $ year_num: num  1984 1985
 $ FY_end  : Date, format: "1984-06-30" "1985-06-30"