Hi Rooters, A few remarks: (1) TH1::GetMaximum() returns the maximum bincontent as long as TH1::SetMaximum() has not been used to set an upper limit on the drawing range. It would be handy to have the drawing range and the actual min/max of the histogram content to be decoupled. The present behaviour is especially annoying if one tries to set the drawing range by hand more than once. The function TH1::GetMaximumStored() seems to be intended to do just this, but only returns -1111 in my version of root. (2) TH1::SetMaximum() takes a Float_t as an argument, even for a TH1D. Likewise, TH1::GetMaximum() returns a Float_t. That leads to trouble for large values in a TH1D. (3) related to (2). Actually having Double_t values in a TH1D (say 1e200), results in an undrawable histogram. The same holds for TF1. (4) if TH1::SetMaximum() has been used to set a maximum, drawing a 2D histogram with the surf option ignores that maximum. The "lego" option works fine. (5) after filling a histogram with TH1::Eval(TF1* f1), switching on the weighted error calculation using TH1::Sumw2() does not work. Also, setting TH1::Sumw2() before using TH1::Eval() has no effect. This is inconsistent with the normal behaviour. (6) it would be very handy if TH1::Eval(TF1* f1, Option_t *option) would also facilitate subtraction, multiplication and division and not just addition. An possible application is fitting a function and then calculating the residuals, or dividing out phasespace. (7) having the "I" option (for integration) in TH1::Eval(TF1* f1) to store the integrated function would be nice. (8) TH1::GetXaxis()->Set(Int_t nbins, Axis_t xmin, Axis_t xmax) allows one to change the number of bins on the axis, without actually changing the number of histogram bins. Filling non-exisitent bins will soon lead to a seg-fault. This should either be implemented properly, or somehow be prevented. Although I have to admit that I wouldn't know a legitimate reason to change the number of bins, changing the upper and lower limit has many usefull applications. I'm using version 2.23/12. That's it for now, -- Gerco Dr. C.J.G. Onderwater Nuclear Physics Laboratory 312 Loomis Laboratory of Physics University of Illinois at Urbana-Champaign 1110 West Green Street Urbana, IL 61801-3080 Phone : (217) 244-7363 Fax : (217) 333-1215 E-mail: onderwat@uiuc.edu
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