Re: st: How blanks are treated when vars are read in as string froman ASCII raw data file

[Ian Watson <ian.watson@tpg.com.au>]

Clare

I just thought of a simple test, which seems to confirm that infile and 
substr produce different results.

Using the substr approach (in yesterday's post):

. list if num=="  1"

     +----------------------+
     |     v1   alpha   num |
     |----------------------|
  1. | B    1       B     1 |
     +----------------------+

Using your infile approach:

. list if siteid=="  1"



ie. nothing.

In other words, infile is stripping out the leading blanks.


--
Kind regards,
Ian

-------------------------------
Ian Watson
Senior Researcher
acirrt, University of Sydney
NSW, 2006, Australia

phone: 02 9351 5622
email:i.watson@econ.usyd.edu.au
www.acirrt.com
-------------------------------




Ian Watson wrote:

> Clare
>
> I've reproduced your problem and compared it with yesterday's solution 
> and can only come up with one suggestion.
>
> When you infile the string and then split it, using the substr function, 
> the right hand component (which I called num in yesterday's post) has 
> leading blanks on it. These are then replaced by leading 0s using the 
> subinstr function.
>
> However, when you infile the string as two strings, Stata possibly 
> strips the leading blanks from it. Even though it has the designation of 
> a str3 type, it may not have the same "contents" as num did (which was 
> also a str3 type) because that latter was created from substr. That
> is " 23" and "23" look the same on the screen, but they're not the same 
> data.
>
> This is only a guess, and I can't find an easy way to test it. But it 
> suggests you're better off reading your string in as a full string, then 
> splitting it, rather than as two strings. At least that works (even if 
> the reason is not altogether clear to me why).
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