R help - Sep 2009 - how to convert character string with only month and year into date

Dear R helpers.

I am new to plotting time data using R.
wonder how to convert character time info into date in R.
I searched over the web but did not find answer.

the input character string is something like 03_1993 or 03-1993, so the
precision is at month level.  I tried the following but failed.
#R code below.

 strptime(c("03_1993"),"%m_%Y")
strptime(c("03-1993"),"%m-%Y")

Can you someone kindly show me to do it?

Many thanks in advance!

-Sean

	[[alternative HTML version deleted]]

Try this:

strptime(paste(1, c("03_1993")),"%d %m_%Y")
strptime(paste(1, c("03-1993")),"%d %m_%Y")

On Tue, Sep 22, 2009 at 4:03 PM, Sean Zhang <seanecon at gmail.com>
wrote:
> Dear R helpers.
>
> I am new to plotting time data using R.
> wonder how to convert character time info into date in R.
> I searched over the web but did not find answer.
>
> the input character string is something like 03_1993 or 03-1993, so the
> precision is at month level. ?I tried the following but failed.
> #R code below.
>
> ?strptime(c("03_1993"),"%m_%Y")
> strptime(c("03-1993"),"%m-%Y")
>
> Can you someone kindly show me to do it?
>
> Many thanks in advance!
>
> -Sean
>
> ? ? ? ?[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.
>


-- 
Henrique Dallazuanna
Curitiba-Paran?-Brasil
25? 25' 40" S 49? 16' 22" O

Try this:
> library(zoo) # as.yearmon
>
> as.yearmon("03_1993", "%m_%Y")
[1] "Mar 1993"
> as.Date(as.yearmon("03_1993", "%m_%Y"))
[1] "1993-03-01"

On Tue, Sep 22, 2009 at 3:03 PM, Sean Zhang <seanecon at gmail.com>
wrote:
> Dear R helpers.
>
> I am new to plotting time data using R.
> wonder how to convert character time info into date in R.
> I searched over the web but did not find answer.
>
> the input character string is something like 03_1993 or 03-1993, so the
> precision is at month level. ?I tried the following but failed.
> #R code below.
>
> ?strptime(c("03_1993"),"%m_%Y")
> strptime(c("03-1993"),"%m-%Y")
>
> Can you someone kindly show me to do it?
>
> Many thanks in advance!
>
> -Sean
>
> ? ? ? ?[[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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.
>

On Sep 22, 2009, at 3:03 PM, Sean Zhang wrote:
> Dear R helpers.
>
> I am new to plotting time data using R.
> wonder how to convert character time info into date in R.
> I searched over the web but did not find answer.
>
> the input character string is something like 03_1993 or 03-1993, so  
> the
> precision is at month level.  I tried the following but failed.
> #R code below.
>
> strptime(c("03_1993"),"%m_%Y")
> strptime(c("03-1993"),"%m-%Y")
>
> Can you someone kindly show me to do it?
>
The usual R classes do not have a year-month version but package zoo  
does:

 > library(zoo)
 > as.yearmon("03_1993","%m_%Y")
[1] "Mar 1993"
>
--

David Winsemius, MD
Heritage Laboratories
West Hartford, CT