Re: [Gretl-users] aggregate by

On Tue, 19 Feb 2013, ahmadou dicko wrote: >> This functionality is not built-in (except in relation to the >> "summary" command, using the --by option). However it's >> possible to write a function to do this sort of thing. The >> following is not very general but should give you the idea: >> >> <hansl> >> function matrix aggregate (series x, series y, string funname) >> matrix m = values(y) ~ 0 >> loop i=1..rows(m) --quiet >> smpl y == m[i,1] --restrict --replace >> m[i,2] = @funname(x) >> printf "@funname(x) for y=%g: %g\n", m[i,1], m[i,2] >> endloop >> colnames(m, "y f(x)") >> return m >> end function >> >> open credscore.gdt >> m = aggregate(Income, Acc, "mean") >> print m >> m = aggregate(Income, Acc, "sd") >> print m >> </hansl> Mmmm. I like it. This as a native function would be very nice to have. Plus, this is one of those cases in which C would be much much faster than hansl.