On Mon, 2005-04-25 at 15:18 -0500, Yong Wang wrote: > Dear R user, > if the dates are in format as "20050425" i.e., Apr. 25 2004" > can you suggest an easy way to transfom it to standard form > as "2005-04-25" or "2004Apr25" or "2005/04/25" or any other > format which is R recognizable? > if there is no easy way to do that, can you let me know what > is the function in R performing similiar function as the "string" > function in C or some other more basic language, so I can loop > through all dates to make the desired change. > thank you > regards
If you are just formatting the Date (ie. no time component) then look at ?as.Date, which has a format argument: > as.Date("20050425", "%Y%M%d") [1] "2005-04-25" Using the format argument, you then return a standard Date class object for use in R. The format argument varies as required for your data format. On the output side, there is the format() function, which has a method for Dates, that you can then use to convert the Date class object into a character vector: > MyDate <- as.Date("20050425", "%Y%M%d") > MyDate [1] "2005-04-25" > format(MyDate, "%B %d %Y") [1] "April 25 2005" Also see ?strftime for details on date format strings. HTH, Marc Schwartz ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html