Hi, Sorry, I forgot to answer the second question. txt<-paste("\\10",unique(month(index(x.1))),"\\2",sep="") #without the as.character() also should work #because str(paste("\\10",unique(month(index(x.1))),"\\2",sep="")) # it returns a character # chr "\\101\\2"
#Here too: str(paste(10,unique(month(index(x.1))),2,sep="")) # chr "1012" #According to the description in paste() "Concatenate vectors after converting to character. " as.POSIXct(gsub("(.*\\-).*(\\-.*)",txt,index(y.1))) #[1] "2004-01-04 01:15:00 EST" "2004-01-04 01:30:00 EST" #[3] "2004-01-04 01:45:00 EST" "2004-01-04 02:00:00 EST" #[5] "2004-01-04 02:30:00 EST" "2004-01-04 03:30:00 EST" #Now, suppose if I want to change both the month and day from the original y.1 index(y.1)<-as.POSIXct(gsub("(.*\\-).*(\\-).*(\\s.*)","\\101\\207\\3",index(y.1))) #Here, the month will be 01 and day 07 y.1 # [,1] #2004-01-07 01:15:00 1 #2004-01-07 01:30:00 2 #2004-01-07 01:45:00 3 #2004-01-07 02:00:00 4 #2004-01-07 02:30:00 5 #2004-01-07 03:30:00 6 Hope it helps. A.K. ________________________________ From: Eric Morway <emor...@usgs.gov> To: arun <smartpink...@yahoo.com> Cc: R help <r-help@r-project.org> Sent: Saturday, November 3, 2012 12:32 PM Subject: Re: [R] override date in xts time series Sys.setenv(TZ="GMT") did the trick! Thank you very much. I'll continue to work the larger problem with this option. Out of curiosity, however, can the following code be modified so that the replacementargument is informed by the month of x.1?: index(y.1)<-as.POSIXct(gsub("(.*\\-).*(\\-.*)","\\101\\2",index(y.1))) Something to the tune of the following seems to work, but is it robust?: txt<-paste("\\10",as.character(unique(month(index(x.1)))),"\\2",sep="") index(y.1)<-as.POSIXct(gsub("(.*\\-).*(\\-.*)",txt,index(y.1))) index(y.1) # "2004-01-04 01:15:00 PST" "2004-01-04 01:30:00 PST" # "2004-01-04 01:45:00 PST" "2004-01-04 02:00:00 PST" # "2004-01-04 02:30:00 PST" "2004-01-04 03:30:00 PST" What would the gsub 'pattern' string be to replace the day, if I may ask? I'm not trying to push my luck, but the gsub approach is new to me and don't quite follow everything that is going on. -Eric ______________________________________________ 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.