Something strange. Your example work but... I have a zoo object. I extract its element 21
>> index(test[21]) > [1] (05/12/05 23:00:00) > >> index(test[21])+1/24 > [1] (05/12/05 24:00:00) > > Why 24:00 ? >> packageDescription("chron")$Version > [1] "2.3-35" >> R.version.string > [1] "R version 2.11.1 (2010-05-31)" > packageDescription("zoo")$Version [1] "1.7-0" cheers -- View this message in context: http://r.789695.n4.nabble.com/Bug-on-chron-tp2533135p2533194.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.