hi, to turn year and week into the date one can do the following:
as.Date('2018 05 Sun', "%Y %W %a") however, when we want the Sunday (1st day of week) of the 1st week of 2018 we get NA because 1/1/2018 was on Monday as.Date('2018 00 Mon',format="%Y %U %a") ## 2018-01-01 as.Date('2018 00 Sun',format="%Y %U %a") ## NA btw the same goes for last week as.Date('2017 53 Sun',format="%Y %U %a") ## 2017-12-31 as.Date('2017 53 Mon',format="%Y %U %a") ## NA So my question is : how do i get from "2018 00 Sun" to 2018-12-31 and from "2017 53 Mon" to 2018-01-01 i realize i can loop over days of week and do some if/then statements, but is there a built in function? thank you peter -- Peter Salzman, PhD Department of Biostatistics and Computational Biology University of Rochester [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.