[ROOT] TMath::BesselJ problem

From: Tom Gutierrez (tgutierr@lifshitz.ucdavis.edu)
Date: Wed Apr 02 2003 - 09:22:46 MEST 

Hi,
Below is a trivial application of TMath to plot some Bessel functions.
Uncomment your favorite one to plot.  However, while the BesselI's and 
BesselK's work fine, the BesselJ's and BesselY's 
no longer seem to be recognized by TMath -- even though the root 
TMath documentation claims otherwise.  I'm using root v.3.02/07 
(root4star) on a linux cluster (pdsf).  There must be something silly 
I'm missing here...

Thanks in advance,
Tom



#include "TMath.h"

Double_t kp2da(Double_t* x, Double_t* par)
{
    double corr=TMath::BesselJ0(x[0]*par[0]);
//    double corr=TMath::BesselY0(x[0]*par[0]);
//    double corr=TMath::BesselJ1(x[0]*par[0]);
//    double corr=TMath::BesselY1(x[0]*par[0]);

//    double corr=TMath::BesselI0(x[0]*par[0]);
//    double corr=TMath::BesselK0(x[0]*par[0]);
//    double corr=TMath::BesselI1(x[0]*par[0]);
//    double corr=TMath::BesselK1(x[0]*par[0]);
    return corr;
}

void testbessel(){

TF1* fun1= new TF1("fun1",kp2da,0,3,1);
fun1->SetParameter(0,1);
fun1->Draw();

}

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