[Gretl-devel] Bugs, missing features and a suggestion

[Riccardo (Jack) Lucchetti]

On Mon, 15 Oct 2007, andreas.rosenblad at ltv.se wrote:

>> svetosch at gmx.net @ INTERNET skrev 2007-09-25 14:02:40 :
>>
>>> andreas.rosenblad at ltv.se schrieb:
>>>
>>>>
>>>> If it is a missing feature, please do implement it, so that the the
>>>> combined expression X = 1 & Y = 2 can be used for matrices
>>>
>>> I'm not against that feature, but note that you can do for example
>>> ((x=1).*(y=2) = 1), or ((x=1)+(y=2) = 2).
>>
>>
>> Yes, but it is more cumbersome and less intuitive. Especially since X = 1
> &
>> Y = 2 is allowed for scalars and data series, it should also be allowed
> for
>> matrices.
>
>
> Is there any chance that Z = (X = 1 & Y = 2) will be allowed for matrices
> too, considering that it is allowed for scalars and data series?

The truble is the OR operator. The output of (X=1) is a matrix; (Y=2) is 
a matrix too. What should (X=1) | (Y=2) be? Concatenation or logical OR? 
Perhaps for this kind of things we should introduce the ".&" and ".|" 
operators.

In the meantime, I see nothing wrong with Sven's suggestion to use
(X=1) .* (Y=2).

Riccardo (Jack) Lucchetti
Dipartimento di Economia
Università Politecnica delle Marche

r.lucchetti at univpm.it
http://www.econ.univpm.it/lucchetti