extracting months from a data

On Mar 9, 2016, at 7:15 PM, Dalthorp, Daniel <ddalthorp at usgs.gov> wrote:

Or: 

x <- c( "3-Oct", "10-Nov" )
format(as.Date(paste0(x,rep("-1970",length(x))),format='%d-%b-%Y'),'%b')

# the 'paste0' appends a year to the text vector
# the 'as.Date' interprets the strings as dates with format  10-Jun-2016 (e.g.)
# the 'format' returns a string with date in format '%b' (which is just the name of the month)

On Wed, Mar 9, 2016 at 3:52 PM, Jeff Newmiller <jdnewmil at dcn.davis.ca.us <mailto:jdnewmil at dcn.davis.ca.us>> wrote:
Your dates are incomplete (no year) so I suggest staying away from the date functions for this. Read ?regex and ?sub.

x <- c( "3-Oct", "10-Nov" )
m <- sub( "^\\d+-([A-Za-z]{3})$", "\\1", x )

--
Sent from my phone. Please excuse my brevity.

On March 9, 2016 10:14:25 AM PST, KMNanus <kmnanus at gmail.com <mailto:kmnanus at gmail.com>> wrote:

I have a series of dates in  format 3-Oct, 10-Oct, 20-Oct, etc.

I want to create a variable of just the month.  If I convert the date
to a character string, substr is ineffective because some of the dates
have 5 characters (3-Oct) and some have 6 (10-Oct).

Is there a date function that accomplishes this easily?

Ken
kmnanus at gmail.com <mailto:kmnanus at gmail.com>
914-450-0816 (tel)
347-730-4813 (fax)

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