Re: [Gretl-users] the aggregate() function

On Thu, 28 Feb 2013, Pindar wrote: > I really appreciate the new functionalities of aggregate()! Glad you like! > At first some comments: > a) including the cases is very useful > b) in terms of the NaN rows in a matrix, well I'm not that sure, in my > function I skip them at the moment, but perhaps sometimes > it's exactly those combinations one likes to know. Is there already a > way that generates a copy of a matrix without lines including missings? Yes: <hansl> m = aggregate(X, A, mean) m = selifr(m, !isnan(m[,cols(m)])) </hansl>

> c) what about the mcov() function as 'aggregator function'? I don't see how that could work, since mcov() takes a matrix argument and returns a matrix. If you had exactly 2 x-variables then I suppose cov() or corr() could be used as the aggregator.

> Second, I'm of the opinion that there is a quite important and user friendly > option missing: > It's about combinatorics. > Although one has e.g. 5 discrete variables one wants e.g. ONLY ALL BIVARIATE > combinations. > This should be done by GRETL and not by hand. Well, I'm not sure about that, since it's trivial to write your own wrapper to do that sort of thing, as in

<hansl> list A = female college ages list X = pizza income matrix amat = A scalar ny = cols(amat) loop i=1..ny -q loop j=i+1..ny -q list Bin = amat[i] amat[j] m = aggregate(X, Bin, mean) print m endloop endloop </hansl> Allin Cottrell _______________________________________________ Gretl-users mailing list Gretl-users(a)lists.wfu.edu http://lists.wfu.edu/mailman/listinfo/gretl-users