Re: st: Fwd: Converting weekly data of form yyyyww

[Nick Cox <njcoxstata@gmail.com>]

Don't -encode-, -destring-,  or use -real()- directly, which avoids  
creation of new variables. For example, -encode- would map "2009",  
"2010", "2011" to 1,2,3, not at all what you want.

Mapping anybody's else "weeks" onto Stata's weeks is still going to be  
a problem, however.

On 25 Jul 2012, at 13:55, Ruth Gilgenbach <rgrune@gmail.com> wrote:

> I have a data set with variable "dates" which are of the form yyyyww,
> and I am trying to convert them to a useable format, and am having no
> luck. I am running Stata 12.
>
> For example, if I use the following
> ************************
> inp str06 dates
> 201002
> 200953
> 201102
> 200935
> end
>
> gen delivery = weekly(dates,"YW")
> *************************
>
> I get the result: (4 missing values generated) rather than the  
> correct result.
>
> I know that the 53-week year in 2009 is also going to pose a problem,
> but this problem persists even in the absence of week 53.
>
> I have also attempted to split the string into components and build
> the dates from these, but I receive the same problem, that missing
> values are generated rather than the values themselves:
>
> ******************
> inp str06 dates
> 201002
> 200953
> 201102
> 200935
> end
>
> gen year =substr(dates,1,4)
> encode year, generate(nyear)
> gen week = substr(dates,5,2)
> encode week, generate(nweek)
>
> gen delivery2 = yw(nyear,nweek)
> *********************************
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/