Hi Laurent,
Thanks for reporting this problem with TH2::FillRandom. Now fixed
in my development version 2.24/03. The same problem was also in
TH3::FillRandom. The code of these two functions was only correct
when the X and Y ranges were identical.
Rene Brun
On Fri, 21 Apr 2000, Laurent APHECETCHE wrote:
> Hi,
>
> I am using the TH2::FillRandom method to fill histograms with some 2D
> distribution.
> I was using so far the following (slightly modified here) macro, and
> was happy with it (I was using quite old 2.21/08 HP-UX/CC Root version).
> If I try now with Root 2.23/12 Linux RH6.1, I obtain strange result for
> the Y-Projection of the histogram (h10_py)...
> Am I doing something obviously wrong or is there a problem with the
> FillRandom method ?
>
> Thanks,
>
>
> ---
>
> {
> Float_t KPIMAX = 40 ;
> Int_t NCX=180 ;
> Int_t NCY=100 ;
> char fileout[80] ;
>
> TCanvas* c1 = new TCanvas("c1","c1",500,500) ;
> TF2* f2 = new
> TF2("f2","y**[0]*exp(-y/[1])/(1+exp((y-[2])/[3]))*sin(x*3.141592653590e+00/180.0)",0,180,0,KPIMAX)
> ;
>
> f2->SetParameters(0.6,17,30,2) ;
> f2->Draw("LEGO") ;
> c1->Update() ;
> c1->Clear() ;
>
> c1->Divide(2,2) ;
>
> TH2F* h2 = (TH2F*)f2->GetHistogram() ;
> h2->SetName("h2") ;
>
> h2->ProjectionX() ;
> h2->ProjectionY() ;
>
> c1->cd(1) ;
> h2_py->Draw() ;
> c1->cd(2) ;
> h2_px->Draw() ;
>
> TH2F* h10 = new TH2F("h10","h10",NCX,0,180,NCY,0,KPIMAX) ;
> h10->FillRandom("f2",1e5) ;
>
> h10->ProjectionX() ;
> h10->ProjectionY() ;
>
> c1->cd(3) ;
> h10_py->Draw() ;
> c1->cd(4) ;
> h10_px->Draw() ;
> }
>
> --
> Dr. Laurent APHECETCHE (mailto:aphecetc@in2p3.fr) | TAPS/PHENIX/ALICE
> SUBATECH-Ecole des Mines de Nantes-4 rue Alfred Kastler-44070 NANTES
> cedex 03
> TEL (+33/0) 2 51 85 84 17 - FAX (+33/0) 2 51 85 84 24 (France)
> http://www-subatech.in2p3.fr/~photons -
> http://www.phenix.bnl.gov/~aphecetc
>
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