Re: st: Mata void functions and pointers

[brendan.halpin@ul.ie (Brendan Halpin)]

On Thu, May 17 2012, Matthew Baker wrote:

> Dear listers:
>
>      I have a problem in which I am trying to populate the elements of
> a pointer with the results of a function. The problem is, the function
> is void and returns its results through an argument, which makes
> getting results into a pointer nontransparent. As a simple example,
> consider the following:

Perhaps I misunderstand your purpose: I assume you want a vector of
results, not necessarily pointers to a result. 

This code achieves that:

/* Begin example */
clear all
mata
void example(A,B,Ab) Ab=A*B

P=J(3,1,0) // <--- 0 not NULL
 
Ab = .     // <--- needs to exist

for (i=1;i<=3;i++) {
   example(i,i,Ab)

   P[i]=Ab // <--- No "&"

   }

/* Display results */

for (i=1;i<=3;i++) {
	P[i]   // <--- no need to dereference
   }
end
/* end example */


Regards,

Brendan
-- 
Brendan Halpin,   Department of Sociology,   University of Limerick,   Ireland
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