You need to specify the origin: as.Date(730456, origin = "matlabs origin date")
HTH, Josh P.S. Alternately, you may be able to do something like: ## find R's numeric representation of 02-Dec-1999 and use the difference from Matlabs to offset MatLabROffset <- 730456 - as.numeric(as.Date("1999-12-02")) as.Date(730456 - MatLabROffset) On Sat, Jul 16, 2011 at 8:50 PM, Eduardo M. A. M. Mendes <emammen...@gmail.com> wrote: > Hello > > I am new to R and I need to convert some dates (numeric format by matlab) to > actual dates in R. > > For instance, > > Matlab -> 730456 -> >> datestr(730456) > > ans = > > 02-Dec-1999 > > R - > >> library(zoo) >> as.Date(730456) > [1] "3969-12-03" > > I don't not mind the output format but it needs to be right. > > > Many thanks > > Ed > > ______________________________________________ > 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. > -- Joshua Wiley Ph.D. Student, Health Psychology University of California, Los Angeles https://joshuawiley.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.