I'm new to R and have the following problem with difftime: if I directly assign date/time strings in difftime I get the expected result:
> a<-"2010-03-23 10:52:00" > a [1] "2010-03-23 10:52:00" > b<-"2010-03-23 11:53:00" > u2<-as.difftime(c(a,b), format ="%Y-%m-%d %H:%M:%S", units="mins") > u2 Time differences in mins [1] -18008 -17947 attr(,"tzone") However, if I first assign the values of "a" and "b" from a data frame within a loop I get a different result: a<-u[i] > a [1] 2010-03-23 10:52:00 6838 Levels: 2010-03-18 16:54:00 2010-03-18 16:55:00 ... 2010-03-23 11:53:00 b<-u[i+1] > b [1] 2010-03-23 11:53:00 6838 Levels: 2010-03-18 16:54:00 2010-03-18 16:55:00 ... 2010-03-23 11:53:00 u2<-as.difftime(c(a,b), format ="%Y-%m-%d %H:%M:%S", units="mins") > u2 Time differences in mins [1] 6837 6838 So, how do use difftime in the context of a loop? Thanks. -- View this message in context: http://n4.nabble.com/using-difftime-tp1751607p1751607.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.