Thanks a lot for your answer. It is something that I do not understand with R how the wrapper functions work really. As an example, check the code below  TimeDiffInSeconds<-diff((ISOdate(timeMatrix[,1],timeMatrix[,2],timeMatrix[,3],timeMatrix[,4],timeMatrix[,5],timeMatrix[,6])),units="secs");       returns an error
even though I make it   TimeDiffInSeconds<-difftime((ISOdate(timeMatrix[,1],timeMatrix[,2],timeMatrix[,3],timeMatrix[,4],timeMatrix[,5],timeMatrix[,6])),units="secs");       I would like to thank you in advance for your help B.R Alex ________________________________ From: Jeff Newmiller <jdnew...@dcn.davis.ca.us> Cc: "R-help@r-project.org" <R-help@r-project.org> Sent: Monday, October 10, 2011 12:23 PM Subject: Re: [R] Handling Time in R No, read ?difftime and look at as.double. There is a units parameter that you must set if you want predictable results. --------------------------------------------------------------------------- Jeff Newmiller The ..... ..... Go Live... DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... Live: OO#.. Dead: OO#.. Playing Research Engineer (Solar/Batteries O.O#. #.O#. with /Software/Embedded Controllers) .OO#. .OO#. rocks...1k --------------------------------------------------------------------------- Sent from my phone. Please excuse my brevity. Do you mean something like that? > > >as.double(diff(c(ISOdatetime(2011,6,1,11,59,1.09),ISOdatetime(2011,6,5,11,59,1.09))),length=20) >[1] 345600 > > > > > >________________________________ >From: Jeff Newmiller <jdnew...@dcn.davis.ca.us> >Cc: "R-help@r-project.org" <R-help@r-project.org> >Sent: Monday, October 10, 2011 10:42 AM >Subject: Re: [R] Handling Time in R > > >Difftime doesn't "report" things. When you print it, it automatically selects >an appropriate human-readable unit to display in, but that does not change its >internal representation. If you must convert to seconds, you can do so using >the as.double generic (as.double.difftime) with a units parameter. >--------------------------------------------------------------------------- >Jeff Newmiller The ..... ..... Go Live... >DCN:<jdnew...@dcn.davis.ca.us> Basics: ##.#. ##.#. Live Go... >Live: OO#.. Dead: OO#.. Playing >Research Engineer (Solar/Batteries O.O#. #.O#. with >/Software/Embedded Controllers) .OO#. .OO#. rocks...1k >--------------------------------------------------------------------------- >Sent from my phone. Please excuse my brevity. > > >Thanks a lot. >> >>That helped. >>One thing now is to have the difftime(y,x) to always report seconds. There >>are times that there is a change in the day and thus the diff will report few >>days difference. How can it always report only seconds? >> >>I would like to thank you in advance for your help >> >>B.R >>Alex >> >> >> >>>>________________________________ >> >>From: jim holtman <jholt...@gmail.com> >> >>Cc: "R-help@r-project.org" <R-help@r-project.org> >>Sent: Friday, October 7, 2011 5:34 PM >>Subject: Re: [R] Handling Time in R >> >>?ISOdatetime >> >> >>> x <- ISOdatetime(2011,10,6,16,23,30.539) >>> str(x) >>POSIXct[1:1], format: "2011-10-06 16:23:30" >>> y <- ISOdatetime(2011,10,6,16,23,30.939) >>> difftime(y,x) >>Time difference of 0.3999999 secs >>> >> >> >> >>> Dear all, >>> I would like to ask your help regarding handling time stamps in R. I think first I need a reference to read about their logic and how I should handle them. >>> >>> For example, this is a struct I have >>> >>> >>> str(MyStruct$TimeStamps) >>> �num [1:100, 1:6] 2011 2011 2011 2011 2011 ... >>> >>> MyStruct$TimeStamps[1,] >>> [1] 2011.000�� 10.000��� 6.000�� 16.000�� 23.000�� >>> 30.539 >>> >>> the last field contains seconds.milliseconds. >>> >>> How I can for example make calculations with time stamps like see if the >>> MyStruct$TimeStamps[1,]-MyStruct$TimeStamps[2,] differ more than >>> 300millisecond, or 3 days have passed? >>> >>> I would like to thank you in advance for your suggestions >>> >>> B.R >>> Alex >>> >>> � � � �[[alternative HTML version deleted]] >>> >>> >>> >>________________________________ >> >>> R-help@r-project.org mailing list< br />> https://stat.ethz.ch/mailman/listinfo/r-help >>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >>> and provide commented, minimal, self-contained, reproducible code. >>> >>> >> >> >> >>-- >>Jim Holtman >>Data Munger Guru >> >>What is the problem that you are trying to solve? >>[[alternative HTML version deleted]] >> >>>>________________________________ >> >>R-help@r-project.org mailing list >>https://stat.ethz.ch/mailman/listinfo/r-help >>PLEASE do read the posting guide http://www.R-project.org/posting-guide.html >>and provide commented, minimal, self-contained, reproducible code. >> > > [[alternative HTML version deleted]]
______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
