[R] Convert day of year back into a date format.

Sam Albers tonightsthenight at gmail.com
Tue Mar 27 20:12:48 CEST 2012


I am having trouble figuring out how to convert a Day of Year integer
back into a Date format. For example I have the following:

date <- c('2008-01-01','2008-01-02','2008-01-03','2008-01-04','2008-01-05','2008-01-06','2008-01-07',

## this is then converted into a number corresponding to the day of
the year like so:

dayofyear <- strptime(date, format="%Y-%m-%d")$yday + 1

## Now my question is how do I get back to a date format (obviously
omitting the year).
## The end result is that I'd like to be able to have axis labels as
something like "Month-Day" or just "Month"
## instead of just an integers which isn't always intuitive for people
but I can't seem to figure out how to tell R
## to recognize an integer as a date.

Any suggestions?

Many thanks in advance!


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