st: Re: function el() fails

[Kit Baum <baum@bc.edu>]

< >
This program works fine. The problem is the evil notion that allows  
Stata to consider variable abbreviations.  I always have the setting

set varabbrev off

and with varabbrev off the program works fine. If you turn it on the  
program fails with 'type mismatch' on the last statement. Clearly the  
parser, with varabbrev on, is mistakenly looking around for variables  
whose names begin with p. This does appear to be a bug, because Stata  
should be looking for a MATRIX name as the first argument to the el()  
function. It should not examine the namespace of variables, whether or  
not their names are abbreviated.

Kit Baum, Boston College Economics and DIW Berlin
http://ideas.repec.org/e/pba1.html
An Introduction to Modern Econometrics Using Stata:
http://www.stata-press.com/books/imeus.html


On Aug 16, 2008, at 02:33 , Sergiy wrote:


> // ----- BEGIN -------
>   sysuse auto
>
>   matrix p=1
>   matrix a=p
>
>   matrix dir
>
>   matrix list a
>   di a[1,1]
>   di el(a,1,1)
>
>   matrix list p
>   di p[1,1]
>   di el(p,1,1)
> // ----- END -------
>
> According to the help file for Stata 9:
>
> el(A,i,j)       the i,j element of A (same as A[i,j])
>
> Note that the program above works for matrix name "a" and not "p".
> This made it difficult to identify the problem. Because the problem is
> observed for some datasets and not for others.
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