Full_Name: Rene Locher Version: 2.7.2 Patched (2008-09-12 r46541) OS: XP Submission from: (NULL) (160.85.231.40)
dat <- data.frame(event=factor(c("A","A","B")), time=as.POSIXct(c("2008-01-10","2008-01-01","2008-01-04"))) min(dat$time) ## "2008-01-01 CET" ## as expected aggregate(dat$time,by=list(event=dat$event),min) ## results in ## event x ## 1 A 1199142000 ## 2 B 1199401200 ## I expected: ## event x ## 1 A "2008-01-01 CET" ## 2 B "2008-01-04 CET" ## my system: sessionInfo() ## R version 2.7.2 Patched (2008-09-12 r46541) ## i386-pc-mingw32 ## ## locale: ## LC_COLLATE=German_Switzerland.1252;LC_CTYPE=German_Switzerland.1252;LC_MONETARY=German_Switzerland.1252;LC_NUMERIC=C;LC_TIME=German_Switzerland.1252 ## ## attached base packages: ## [1] stats graphics grDevices utils datasets methods base Kind regards Rene Locher E-Mail: [EMAIL PROTECTED] Institute for Data Analysis and Process Design Tel: +41 58 934 7810 Zurich University of Applied Sciences Fax: +41 58 935 7810 Rosenstrasse 3 Postfach CH-8401 Winterthur http://www.idp.zhaw.ch ______________________________________________ R-devel@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-devel