Re: AW: st: -if- and r() in -histogram-

[Antoine Terracol <Antoine.Terracol@univ-paris1.fr>]

So I guess that to be on the safe side one should use `r()' in every 
-if- statement. That should be made clearer in [U]18, section 18.8. 
There might be technical reasons, but why not mark the relevant 
subsample right after parsing the command, rather than when the content 
of the -if- statement could have been modified by subroutines?

Antoine



Nick Cox wrote:
> `r(95)' is evaluated before -histogram- even opens: -histogram- sees only the numeric result. 
>
> That's not true of r(95). In the first instance the text "r(95)" is used and only later it is evaluated. 
>
> That is, you want -histogram- to work with a pre-existing r(95), but inside -histogram- other r-class results are produced and that undermines your aim. 
>
> Nick 
> n.j.cox@durham.ac.uk 
>
> Antoine Terracol
>
> True, but I find it strange that references to r() work with -kdensity- 
> (or commands like -summarize-), but hot with -histogram- (nor with 
> -graph box-) where `r()' seems to be required.
>
> Martin Weiss wrote:
> > <> 
> >
> > You do get the correct graph with:
> >
> > *************
> > clear
> > cap graph drop _all
> > set obs 1000
> > g x=exp(rnormal())
> > su x, de
> > hist x if x<`r(p95)', name(ha)
> > *************
> >
> >
> >
> > HTH
> > Martin
> >
> > -----Ursprüngliche Nachricht-----
> > Von: owner-statalist@hsphsun2.harvard.edu
> > [mailto:owner-statalist@hsphsun2.harvard.edu] Im Auftrag von Antoine
> > Terracol
> > Gesendet: Donnerstag, 4. Februar 2010 13:24
> > An: statalist@hsphsun2.harvard.edu
> > Betreff: Re: st: -if- and r() in -histogram-
> >
> > <>
> >
> > of course, all the "hist" below should be "kdensity", and the correct 
> > piece of code is
> >
> > /**********************/
> > clear
> > cap graph drop _all
> > set obs 1000
> > g x=exp(rnormal())
> > su x, de
> > local p95=r(p95)
> > di r(p95)
> > kdensity x if x<r(p95), name(ka)
> > kdensity x if x<`p95', name(kb)
> > kdensity x, name(kc)
> > /************************/
> >
> > Antoine Terracol wrote:
> > > Now, I have not tried all types of graphs, but -kdensity- seems to 
> > > behave as expected:
> > >
> > > /**********************/
> > > clear
> > > cap graph drop _all
> > > set obs 1000
> > > g x=exp(rnormal())
> > > su x, de
> > > local p95=r(p95)
> > > di r(p95)
> > > hist x if x<r(p95), name(ka)
> > > hist x if x<`p95', name(kb)
> > > hist x, name(kc)
> > > /************************/
>
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