Bookmark and Share

Notice: On March 31, it was announced that Statalist is moving from an email list to a forum. The old list will shut down at the end of May, and its replacement, statalist.org is already up and running.


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

RE: st: wildcard in numeric variable


From   tashi lama <ltashi32@hotmail.com>
To   <statalist@hsphsun2.harvard.edu>
Subject   RE: st: wildcard in numeric variable
Date   Fri, 1 Jun 2012 14:26:01 +0000

I have an example that fails to replace string var using wildcard in expression. I tried this and it fails... Any idea? var1 is string. 

 

 

var1 

abc

ab

d

e

 

replace var1="" if var1=="a*"

0 obs replaced. 

 

Tashi
----------------------------------------
> From: n.j.cox@durham.ac.uk
> To: statalist@hsphsun2.harvard.edu
> Date: Fri, 1 Jun 2012 12:50:06 +0100
> Subject: RE: st: wildcard in numeric variable
>
> Missing ) inserted below.
>
> Nick
> n.j.cox@durham.ac.uk
>
>
> -----Original Message-----
> From: owner-statalist@hsphsun2.harvard.edu [mailto:owner-statalist@hsphsun2.harvard.edu] On Behalf Of Nick Cox
> Sent: 01 June 2012 12:35
> To: 'statalist@hsphsun2.harvard.edu'
> Subject: RE: st: wildcard in numeric variable
>
> The second argument of the -string()- function if you need it should be a _numeric_ display format. That's because you are specifying how a number should be displayed. Try something like
>
> ... if substr(string(numvar, "%20.0f"), 1, 4) == "9999"
>
> for "any suitable value of 20". (I think this was a Salomon Bochner joke.)
>
> Nick
> n.j.cox@durham.ac.uk
>
>
> -----Original Message-----
> From: owner-statalist@hsphsun2.harvard.edu [mailto:owner-statalist@hsphsun2.harvard.edu] On Behalf Of Colin Campbell
> Sent: 01 June 2012 12:27
> To: statalist@hsphsun2.harvard.edu
> Subject: Re: st: wildcard in numeric variable
>
> Thank you Nick,
>
> the solution
>
> ... if substr(string(numvar), 1, 4) == "9999"
>
> looks great and nearly works a treat. But, this solution will not replace those with 8 or more digits.
> I assume this has to do with the str format %#s but am not sure how to specify this correctly.
>
> I tried the following:
>
> replace cv =. if substr(string(cv, "%12s"), 1, 4) == "9999"
>
> but this returns "(0 real changes made)". Any other ideas?
>
> Colin
>
>
>
> ----- Original Message -----
> From: Nick Cox <njcoxstata@gmail.com>
> To: statalist@hsphsun2.harvard.edu
> Cc:
> Sent: Friday, 1 June 2012, 10:47
> Subject: Re: st: wildcard in numeric variable
>
> Wildcards don't apply to numeric values.
>
> ... if substr(string(numvar), 1, 4) == "9999"
>
> is the simplest solution that occurs to me. No need for new variables,
> -tostring- or any regex machinery.
>
> Nick
>
> On Fri, Jun 1, 2012 at 9:40 AM, Colin Campbell
> <col.campbell@rocketmail.com> wrote:
> >
> > Dear Statalist,
> >
> > I have a dataset in which a numeric variable cv contains values that need to be coded as missing.
> > There are a variety of numeric values 9999, 99999, 999999 etc that need to be recoded.
> > While I could replace each value individually, I wondered if there is a way to use wildcards with numeric variables such that e.g.
> >
> >
> > replace numvar =. if numvar == 9999*
> >
> > would work. I have a workaround using string variables as follows
> >
> > tostring cv, gen(cv_str)
> > gen cv_mis = regexm(cv_str, "9999")
> > replace cv =. if cv_mis ==1
> > drop cv_mis cv_str
> >
> > Is there a more elegant way to achieve this without resorting to strings?
>
>
> *
> * 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/ 		 	   		  
*
*   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/


© Copyright 1996–2014 StataCorp LP   |   Terms of use   |   Privacy   |   Contact us   |   Site index