[R] Parsing unusual date format

[Phil Spector]

You can use regular expressions:
as.Date(sub('(\\d+)m(\\d+)','\\1-\\2-01',dts,perl=TRUE))

but as.Date isn't as inflexible as you think:
as.Date(paste(dts,'m01',sep=''),'%Ym%mm%d')

                                        - Phil Spector
 					 Statistical Computing Facility
 					 Department of Statistics
 					 UC Berkeley
 					 spector at stat.berkeley.edu


On Thu, 18 Dec 2008, markleeds at verizon.net wrote:

> hi: i tried regular expressions and , as usual, failed. but below does do the 
> job uglily using strsplit. i'd still be curious and appreciate if someone 
> could do the regular expression method. thanks.
>
> dts <- c("1990m12", "1992m8") #March 1990 and Aug 1992
>
> #SPLIT IT USING m
> temp <- strsplit(dts,"m")
>
> # PASTE THE #'S BUT CHECK
> # FOR GREATER THAN 9 UGLIFIES IT
> moddates <- lapply(temp,function(.str) {
>  if ( as.numeric(.str[2]) > 9 ) {
>    paste(.str[1],as.numeric(.str[2]),"01",sep="-")
>  } else {
>    paste(.str[1],"-0",as.numeric(.str[2]),"-01",sep="")
>  }
> })
>
> # MAKE  THE DATE
> datelist<-lapply(moddates,as.Date ,format="%Y-%m-%d")
>
>
>
>
> On Thu, Dec 18, 2008 at  1:14 AM, Shruthi Jayaram wrote:
>
>> Hello,
>> 
>> If I have a character string like
>> 
>> d <- c("1990m3", "1992m8") #March 1990 and Aug 1992
>> 
>> what is the easiest way to convert it into any standard date form; for
>> example,
>> 
>> d <- c("01/03/1990", "01/08/1992")
>> I looked at as.Date but it doesn't seem to address my problem as I have an
>> "m" stuck in the middle of my character string which R does not recognise.
>> 
>> Would be very grateful for any help on this.
>> Shruthi
>> -- 
>> View this message in context: 
>> http://www.nabble.com/Parsing-unusual-date-format-tp21067562p21067562.html
>> Sent from the R help mailing list archive at Nabble.com.
>> 
>> ______________________________________________
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>
> ______________________________________________
> R-help at r-project.org mailing list
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> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>