David,
see: http://root.cern.ch/root/htmldoc/TF1.html
and look at the section;
WHY TF1 CANNOT ACCEPT A CLASS MEMBER FUNCTION ?
Rene brun
BORRAS David wrote:
>
> Hi Rootters,
>
> I have written a code in FML_Minuit where i minimize a unbinned likelihood
> method. In this code i define a class MyFunction where i implement the
> function to be used in fitter. This function is the convolution between
> exponential and gaussian function. To do this i use functions from CLHEP
> package (AnalyticConvolution.hh).
> I would like only plot this function convolution and i write some "root
> line" for that.
> here is :
>
> // Here is the name of my class
> MyFunction f;
>
> ....some treatments
>
> //To run root
> TApplication theApp(...)
> // create the canvas for plot
> TCanvas *vc ...
>
> and here is my problem :
> TF1 *f1 = new TF1("fct","f",xmin,xmax);
> f1->Draw();
>
> The code compile fine, but when i execute it, i have the following message
> :
> "bad numerical expression "f".The function fct/f has 0 parameters instead
> of 1."
>
> The canvas appears fine and i only have a line in it.
> Is my problem come from the fact that my function is a member of my
> defined class or i make something wrong in the code ?
>
> Cheers, David
> *************************************************
> * David Borras *
> * PhD Student *
> *************************************************
> * Laboratoire de Physique Corpusculaire (LPC) *
> * IN2P3/CNRS *
> * Universite Blaise Pascal *
> * 24 avenue des Landais *
> * 63177 Aubiere Cedex *
> * *
> * tel : 04 73 40 72 77 (work) *
> * mail: borras@clermont.in2p3.fr *
> *************************************************
This archive was generated by hypermail 2b29 : Sun Jan 02 2005 - 05:50:10 MET