How can I create a Month-Day vector in R?-CodePudding

I want to create a vector in R, which contains month abbreviation and date:

Jan1, Jan2, Jan3, ..., Dec29, Dec30, Dec31.

How can I create such a vector?

I have tried different approaches. Using paste0(month.abb,1:31) gives me a vector containing Jan1,Feb2,Mar3.

I also created 12 different vectors for each month (df_jan <- paste0("Jan",1:31) and so on). Then I attempted to rbind the 12 vectors, but that also doesn't help.

Can you suggest any way to do this?

CodePudding user response：

The solution is dependent on the year of the dates. A leap year would have Feb29 in it.

Here's a function which takes year as an argument and return dates in the required format.

monthday <- function(year) {
  format(seq(as.Date(paste0(year, '-01-01')), 
             as.Date(paste0(year, '-12-31')), by = 'day'), '%b%d')
}

monthday(2021)
# [1] "Jan01" "Jan02" "Jan03" "Jan04" "Jan05" "Jan06" "Jan07" "Jan08" "Jan09"
#...
#[55] "Feb24" "Feb25" "Feb26" "Feb27" "Feb28" "Mar01" "Mar02" "Mar03" "Mar04"
#....
#[361] "Dec27" "Dec28" "Dec29" "Dec30" "Dec31"


monthday(2020)
# [1] "Jan01" "Jan02" "Jan03" "Jan04" "Jan05" "Jan06" "Jan07" "Jan08" "Jan09"
#....
#[55] "Feb24" "Feb25" "Feb26" "Feb27" "Feb28" "Feb29" "Mar01" "Mar02" "Mar03"
#....
#[361] "Dec26" "Dec27" "Dec28" "Dec29" "Dec30" "Dec31"

CodePudding user response：

You can create a sequence of dates and convert it using format For more details on POSIX standard format use ?strptime

whole_year_dates <- seq.Date(as.Date("2021-01-01"), as.Date("2021-12-31"), by = "day")

whole_year_dates_abbr <- format(whole_year_dates, format= "%b%d")