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: macro problem


From   Jeph Herrin <stata@spandrel.net>
To   Richard Goldstein <richgold@ix.netcom.com>
Subject   Re: st: macro problem
Date   Mon, 11 Jun 2012 12:17:54 -0400

There is no problem with -strpos-, which never returns missing and which is zero exactly when I want it to be. The problem was in creating the original macro and then referencing the elements so that they appear in -strpos- with the correct number of quotations marks; I was achieving either too many or too few of the latter.

The solution (or at least, a solution) is for local -matchlist- needed to be enclosed in compound quotes, and then ditto the reference:

   local matchlist `""string 1" "string 2" "string 3" .... "string 55""'

   gen byte match=0
   foreach S of local matchlist {
        replace match = 1 if strpos(strvar,`"`S'"')
   }


The reference in -strpos- looks wrong to me - I would anticipate that `S' would include the necessary "'s for -strpos-, but it does not. Without the extra quotes on the original local, however, `"`S'"' resolves to include too many "'s.

cheers,
Jeph


Otherwise,

On 6/11/2012 11:58 AM, Richard Goldstein wrote:
you don't make it clear about what doesn't work

but here is a guess: you are getting match=1 in all cases (or at least
all where strvar is not missing); remember, however, that strpos=0 if
"S" is not found; so, in addition to the quotes, etc., I guess you want
to ensure that strpos is>0 (and maybe<.)

Rich

On 6/11/12 11:50 AM, Jeph Herrin wrote:
This should be trivial, but for some reason I cannot get it.

I have a string variable, and I have a list of string values I need to
match against it. There are occasional trailing or leading characters in
the variable, so I am using -strpos- to find matches. Thus

   local matchlist "string 1" "string 2"  "string 3" .... "string 55"

   gen byte match=0
   foreach S in `matchlist' {
         replace match = 1 if strpos(strvar,`S')
   }

Now, I know I have got the quotes and macro evaluations wrong, but that
is the problem: I've tried this many different ways, and yet cannot seem
to find a combination that works. Any thoughts?

thanks,
Jeph


*
*   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