r-devel, One other question just occurred to me - does R have any concept of times alone? I can see that there's dates, and datetimes (POSIXct etc), but how should I represent 12:34:56 as just a time?
Thanks, Phil > -----Original Message----- > From: Jeff Ryan [mailto:[EMAIL PROTECTED] > Sent: Wednesday, September 17, 2008 4:19 PM > To: Lee, Philip (IT) > Cc: r-devel@r-project.org > Subject: Re: [Rd] Dates in C api > > If you are looking for examples of handling dates/times (specifically > POSIXct) within C code, the dev branch of xts has quite a bit of code > now. > > http://r-forge.r- > project.org/plugins/scmsvn/viewcvs.php/dev/pkg/src/?root=xts > > Assigning the class (or any attribute) within the C code will be much > faster than doing it outside of C, at least in my experience with > larger data. > > setAttrib(ans, R_ClassSymbol, mkString("Date")) > > HTH > Jeff > > On Wed, Sep 17, 2008 at 12:24 PM, Lee, Philip (IT) > <[EMAIL PROTECTED]> wrote: > > r-devel, > > > > I've been trying to write a C plugin for R, and I'm struggling to > > understand how dates are represented. > > > > I can create a date in R: > >> mydate<-as.Date(1, origin="1900-01-01") mydate > > [1] "1900-01-02" > > > > When I pass my date to a plugin, though, it's type is that of a real. > > There doesn't seem to be a date type in Rinternals.h, is there a way > to > > recognize that a value is a date rather than a real? > > > > Equally, does anyone know if it's possible to create date values in > the > > C api? > > > > Thanks, > > Phil Lee > > > > Philip Lee > > Morgan Stanley | Technology > > 750 Seventh Avenue, 12th Floor | New York, NY 10019 > > [EMAIL PROTECTED] > > -------------------------------------------------------- > > > > NOTICE: If received in error, please destroy and notify sender. > Sender does not intend to waive confidentiality or privilege. Use of > this email is prohibited when received in error. > > > > ______________________________________________ > > R-devel@r-project.org mailing list > > https://stat.ethz.ch/mailman/listinfo/r-devel > > > > > > -- > Jeffrey Ryan > [EMAIL PROTECTED] > > ia: insight algorithmics > www.insightalgo.com -------------------------------------------------------- NOTICE: If received in error, please destroy and notify sender. Sender does not intend to waive confidentiality or privilege. Use of this email is prohibited when received in error. ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel
