[R] Week number from a date
Hi My data looks like this startDate=2008-06-01 dateRange =c( 2008-10-01,2008-12-01) Is there any method to find the week number from the startDate range - Thanks in Advance Arun -- View this message in context: http://r.789695.n4.nabble.com/Week-number-from-a-date-tp4410223p4410223.html Sent from the R help mailing list archive at Nabble.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.
Re: [R] Week number from a date
?strptime is a good place to start hth, Ingmar On Wed, Feb 22, 2012 at 2:09 PM, arunkumar akpbond...@gmail.com wrote: Hi My data looks like this startDate=2008-06-01 dateRange =c( 2008-10-01,2008-12-01) Is there any method to find the week number from the startDate range - Thanks in Advance Arun -- View this message in context: http://r.789695.n4.nabble.com/Week-number-from-a-date-tp4410223p4410223.html Sent from the R help mailing list archive at Nabble.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. [[alternative HTML version deleted]] __ 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.
Re: [R] Week number from a date
To give a little more detail, you can convert your character strings into POSIX objects, then extract from it virtually anything you would want using strftime. In particular, %W is how you get the week number: dateRange - c(2008-10-01,2008-12-01) x - as.POSIXlt(dateRange) strftime(x,format=%W) [1] 39 48 --Patrick On 02/22/2012 08:37 AM, Ingmar Visser wrote: ?strptime is a good place to start hth, Ingmar On Wed, Feb 22, 2012 at 2:09 PM, arunkumarakpbond...@gmail.com wrote: Hi My data looks like this startDate=2008-06-01 dateRange =c( 2008-10-01,2008-12-01) Is there any method to find the week number from the startDate range __ 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.
Re: [R] Week number from a date
The suggestion below gives you week numbers with week 1 being the week containing the first monday of the year and weeks going from monday to sunday. There are other conventions. The ISO convention is that week 1 is the first week containing at least 4 days in the new year (week 1 of 2012 starts on 2nd januari; week 1 of 2008 starts on december 29th 2008). http://www.r-bloggers.com/iso-week/ gives a function for that type of week numbers (not tested by me). Jan Patrick Breheny patrick.breh...@uky.edu schreef: To give a little more detail, you can convert your character strings into POSIX objects, then extract from it virtually anything you would want using strftime. In particular, %W is how you get the week number: dateRange - c(2008-10-01,2008-12-01) x - as.POSIXlt(dateRange) strftime(x,format=%W) [1] 39 48 --Patrick On 02/22/2012 08:37 AM, Ingmar Visser wrote: ?strptime is a good place to start hth, Ingmar On Wed, Feb 22, 2012 at 2:09 PM, arunkumarakpbond...@gmail.com wrote: Hi My data looks like this startDate=2008-06-01 dateRange =c( 2008-10-01,2008-12-01) Is there any method to find the week number from the startDate range __ 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. __ 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.
Re: [R] Week number from a date
On Wed, Feb 22, 2012 at 8:09 AM, arunkumar akpbond...@gmail.com wrote: Hi My data looks like this startDate=2008-06-01 dateRange =c( 2008-10-01,2008-12-01) Is there any method to find the week number from the startDate range Is the question how many weeks are from the startDate to each of the dateRange dates? If so, then try this: startDate - as.Date(2008-06-01) dateRange - as.Date(c( 2008-10-01,2008-12-01)) floor(as.numeric(dateRange - startDate) / 7) or depending on what the week is supposed to be we might want ceiling in place of floor or neither floor nor ceiling if we want fractional weeks. -- Statistics Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.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.
