Re: TGraph with non-linear axis

From: Georgy Golovanov <geoang_at_lxmx00.jinr.ru>
Date: Tue, 25 Oct 2005 16:44:26 +0400

Hi,

        I can't use SetLogx() because my function is not exactly Log (see the code below). I defined a new function, then applied one to the TGaxis(). The axis looks fine on the canvas. Is there any way to apply this coordinate axis to the TGraph?
Thanks in advance,

• Georgy.

  ---

Double_t Eta(Double_t *x, Double_t *par) {

    return 2.0*TMath::ATan(TMath::Exp(-1.0*x[0])); }

void AxisTest() {

    gROOT->Reset();

    TCanvas* c1 = new TCanvas("c1", "ddd", 800, 600);     c1->Range(0, 0, 100, 100);         

    TF1* f1 = new TF1("f1", Eta, -4.5, 4.5, 1);

    TGraph* graph;

    TGaxis *A1 = new TGaxis(5, 10, 95, 10, "f1", 50510, "+-", 100);

    A1->SetTextColor(1);
    A1->SetLabelSize(0.02);
    A1->Draw();

}

---

On Tuesday 25 October 2005 16:04, Olivier Couet <Olivier.Couet_at_cern.ch> wrote:
> Hi,
>
> Can you send a running example showing what you are doing ? why don't you
> simply set the option SetLogx() on the canvas ?
>
> O.Couet
>
> On Tue, 25 Oct 2005, Georgy Golovanov wrote:
> > Dear Rooters,
> >
> > I'm trying to draw a TGraph with non-linear X-axis (like Log
> > scale). I've constructed a TGaxis with hand-made function and it looks
> > fine on the canvas, but the problem is how to apply this axis to the
> > TGraph. Is it possible?
> > Thanks for any help,
> >
> > - Georgy
Received on Tue Oct 25 2005 - 14:42:39 MEST