I am currently working with a dataset that has columns for weekdays in a number format. For weekdays the number one represents Monday and 7 Sunday; preliminarily, I am trying to make use of some sort of library that can convert this numbers into string/text format. For example, if I were to pass the vector days I would like to get the number days as text form.
Input:
days<-c(1,3,5,7)
Desired output:
"monday", "wednesday", "friday", "sunday"
I am using the library lubridate in R when running this line of code I get:
> wday(days, week_start = getOption("lubridate.week.start", 1), label = TRUE)
[1] Sun Tue Thu Sat
Levels: Mon < Tue < Wed < Thu < Fri < Sat < Sun
Which is not what I want since number 1 must be Mon and 7 Sun and even if I try to change the parameter week_sart to any number, I still get Sun instead of Mon and thus all other days are incorrect.
> wday(days, week_start = getOption("lubridate.week.start", 7), label = TRUE)
[1] Sun Tue Thu Sat
Levels: Sun < Mon < Tue < Wed < Thu < Fri < Sat
So I ended up running this line to get my desired output:
wday(days+1, week_start = getOption("lubridate.week.start", 1), label = TRUE)
[1] Mon Wed Fri Sun
Levels: Mon < Tue < Wed < Thu < Fri < Sat < Sun
But what I really want to have a function that will set one as mon by default in case I have to work in other machines. How can I properly change the parameters of the lubridate::wday function to get my desired output?
You can do this efficiently without lubridate, using days as an index vector.
w <- tolower(weekdays(.Date(4:10)))
w
## [1] "monday" "tuesday" "wednesday" "thursday" "friday" "saturday" "sunday"
w[days]
## [1] "monday" "wednesday" "friday" "sunday"
If you want a factor, then you can do
gl(7L, 1L, labels = w)[days]
## [1] monday wednesday friday sunday
## Levels: monday tuesday wednesday thursday friday saturday sunday
optionally passing ordered = TRUE to gl.
It's worth mentioning that the weekdays result is locale-dependent. Non-English locales will use non-English names for week days, etc. If you want completely reproducible results, then construct w yourself.
w <- c("monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday")