Converting date with additional characters in format

Question

I have a string variable that I want to parse to class Date. In addition to the day, year and month, the format has other characters like separators (,

Answer 1

You don't need to strip the characters not used in the conversion specification. In the Details section of ?strptime we find that:

"[a]ny character in the format string not part of a conversion specification is interpreted literally"

That is, in the format argument of as.Date, you may include not only the conversion specification (introduced by %) but also the "other characters":

Furthermore, from ?as.Date:

Character strings are processed as far as necessary for the format specified: any trailing characters are ignored

Thus, this works:

as.Date("(u'9', u'2005', u'06')", format = "(u'%d', u'%Y', u'%m")
# [1] "2005-06-09"