Hi Ben,
Thanks for reporting this problem with log scales and the "box" option.
Now fixed in the CVS version.
Rene Brun
On Fri, 14 Jun 2002, Ben Kilminster wrote:
> Hi,
>
> I find that the box option fails for 2-D histograms plotted on a log scale
> for tiny values (some limit in precision for calculating box size ?).
>
> Here is a variation of the log-scale-tutorial showing in canvas 2 that no
> entries are plotted with the box option.
>
> The problem occurs with cint and with aclic, and happens at least as
> recently as root v3_03_05c
>
> Cheers,
> Ben
>
>
> #include "TCanvas.h"
> #include "TH2.h"
> #include "TRandom.h"
> #include "TStyle.h"
>
> void loglog()
> {
>
> TCanvas *c1 = new TCanvas("c1");
> TCanvas *c2 = new TCanvas("c2");
> TCanvas *c3 = new TCanvas("c3");
> gStyle->SetOptStat(1111111);
> c1->SetLogx();
> c1->SetLogy();
> c2->SetLogx();
> c2->SetLogy();
> c3->SetLogx();
> c3->SetLogy();
>
> // box option works
> Axis_t low = 1E-2;
> Axis_t hi = 1E0;
> TH2F *h1 = new TH2F("h1","h1 range 1",40,low,hi,40,low,hi);
>
> // box option fails
> low = 1E-22;
> hi = 1E-19;
> TH2F *h2 = new TH2F("h2","h2 range 2",40,low,hi,40,low,hi);
>
> for (Int_t i=0;i<1000;i++) {
>
> h1->Fill(fabs(1E-2*gRandom->Landau(5,2)),(fabs(1E-2*gRandom->Landau(5,10))));
>
> h2->Fill(fabs(1E-22*gRandom->Landau(5,10)),(fabs(1E-22*gRandom->Landau(5,10))));
> }
> c1->cd();
> h1->Draw("box");
> c2->cd();
> // fails
> h2->Draw("box");
> c3->cd();
> // without box option, it works
> h2->Draw();
> }
>
>
>
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