The problem occurs with Root 3.05/07.
I tried Root 3.04/02 which was also installed in my Solaris environment and the
script works ok.
I will test a more up-to-date version...
Thanks,
Patrick Sizun
>I do not see a problem with the last bin in your example.
>Which version are you using?
>In case you use an old version, please upgrade your system.
>
>Rene Brun
>
>On Tue, 10 Feb
>2004, Patrick SIZUN wrote:
>
>> Hi,
>>
>> I face a problem when drawing a variable bin size histo in log scale.
>> The last channel is not displayed correctly but is much larger than it
should.
>>
>> Below is an example where I just took a script given in the roottalk forum
and
>> changed the minimum to show the phenomenon.
>>
>> Can some one help ?
>>
>> P. Sizun
>>
>> {
>> const Int_t nbins = 100;
>> Double_t xmin = 1e-3;
>> Double_t xmax = 1e3;
>> Double_t logxmin = TMath::log10(xmin);
>> Double_t logxmax = TMath::log10(xmax);
>> Double_t binwidth = (logxmax-logxmin)/nbins;
>> Double_t xbins[nbins+1];
>> xbins[0] = xmin;
>> for (Int_t i=1;i<=nbins;i++) {
>> xbins[i] = xmin + TMath::Power(10,logxmin+i*binwidth);
>> }
>> TH1F *h = new TH1F("h","hist with log x axis",nbins,xbins);
>>
>> Double_t x,xl;
>> for (Int_t j=0;j<10000;j++) {
>> xl = 0.5*(logxmin+logxmax) + 12*binwidth*gRandom->Gaus(0,1);
>> x = xmin + TMath::Power(10,xl);
>> h->Fill(x);
>> }
>> TCanvas *c1 = new TCanvas("c1");
>> c1->SetLogx();
>> h->SetMinimum(-200.0);
>> h->Draw();
>> }
>>
>>
>>
>
*********************************************
Patrick Sizun
CEA-Saclay
DSM/DAPNIA/Service d'Astrophysique
Orme des Merisiers - Bat.709 - S.153
91191 Gif-sur-Yvette Cedex
France
Tel : +33 (0)1 69 08 48 26
Mel : sizun@discovery.saclay.cea.fr
Fax : +33 (0)1 69 08 65 77 / (0)1 69 08 79 96
*********************************************
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