On Fri, 15 May 2020, Poizot Emmanuel writes: > Dear all, > > I've a data frame with a column "Date": > > [1] 11-1993 11-1993 11-1993 11-1993 11-1993 11-1993 11-1996 11-1996 11-1996 > [10] 11-1996 11-1996 11-1996 02-1998 02-1998 02-1998 02-1998 02-1998 02-1998 > [19] 11-1998 11-1998 11-1998 11-1998 11-1998 11-1998 10-2001 10-2001 10-2001 > [28] 10-2001 10-2001 10-2001 02-2003 02-2003 02-2003 02-2003 02-2003 02-2003 > [37] 11-2004 11-2004 11-2004 11-2004 11-2004 11-2004 11-2005 11-2005 11-2005 > [46] 11-2005 11-2005 11-2005 11-2007 11-2007 11-2007 11-2007 11-2007 11-2007 > [55] 10-2008 10-2008 10-2008 10-2008 10-2008 10-2008 03-2009 03-2009 03-2009 > [64] 03-2009 03-2009 03-2009 10-2012 10-2012 10-2012 10-2012 10-2012 10-2012 > [73] 12-2017 12-2017 12-2017 12-2017 12-2017 12-2017 12-2018 12-2018 12-2018 > [82] 12-2018 12-2018 12-2018 > > I want to convert that into real dates: > as.POSIXct(Date, format="%m-%Y") always return "NA" values. > Where am I wrong ? > > regards
If you really want a date, I'd suggest 'as.Date'. The help for ?as.Date says: "If the date string does not specify the date completely, the returned answer may be system-specific." So perhaps try something like as.Date(paste0("01-", "11-1993"), format = "%d-%m-%Y") ## [1] "1993-11-01" Or look at 'yearmon' in package 'zoo': library("zoo") as.yearmon("11-1993", format = "%m-%Y") ## [1] "Nov 1993" -- Enrico Schumann Lucerne, Switzerland http://enricoschumann.net ______________________________________________ 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.