Hi!
Thank you Rene. Your suggestion inplicitly led me to the problem (I didn't
realize that TF1::Streamer() is evaluating the TF1 funtion (saving in
fSave) and some global pointer was not set at that time yet.
But I got to another problem. It seems to me that TF1::Clone() doesn't
work well. I compiled the code below and the function f2 was drawn as
constant 0.
--------------------------------
#include <TROOT.h>
#include <TApplication.h>
#include <TGClient.h>
#include <TF1.h>
Double_t coocoo(Double_t *x, Double_t *par) {
Double_t xx = *x - par[0];
return xx * xx - 1;
}
extern void InitGui();
VoidFuncPtr_t initfuncs[] = { InitGui, 0 };
TROOT root("GUI", "GUI test environement", initfuncs);
int main(int argc, char **argv)
{
TApplication *Appp = new TApplication("App", &argc, argv);
TF1 *f1 = new TF1("f1", coocoo, -3, 3, 1);
f1 -> SetParameter(0, 1);
f1 -> Draw();
TF1 *f2 = (TF1*) f1->Clone();
f2 -> SetParameter(0, -1);
f2 -> Draw("same");
Appp->Run(1);
}
-----------------------------------
On Mon, 9 Apr 2001, Rene Brun wrote:
> Hi Miha,
>
> Cloning an object (TObject *obj) is done via obj->Clone().
> This function creates a new object of your class by calling
> its default constructor, then calls the Streamer function of your class to
> copy the members.
>
> You must make sure that your constructor initializes correctly all members, in
> particular the pointers. In your case, one of the pointers fCTFoonc,
> fTFoonc, fLst or fMoother is probably not set. Check also the constructor
> of your class TFoonction for similar symptoms.
>
> Rene Brun
>
> miha.puc@marvin.fmf.uni-lj.si wrote:
> >
> > Hi!
> > I'm new to roottalk.
> > So can anybody help me?
> > I wrote a class having the following data members:
> >
> > class TFoonction : public TNamed {
> > protected:
> > Int_t fNprs;
> > Int_t fMyIdx;
> > Int_t fMyIdxGlobal;
> > Double_t fXmin, fXmax;
> > TF1 *fCTFoonc;
> > TF1 *fTFoonc;
> > TList *fLst;
> > TFoonction* fMoother;
> >
> > If I try to clone an object of this class I get a segfault.
> > I rely on rootcint to generate the Streamer function.
> > I only tried if with compiled code. I use ROOT v 3.00/06 RH Linux 6.2.
> >
> > Miha
> > --
>
--
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