Facing problem in writing a function in root

[priyanshu-gif]

how to write crystal ball function in root?

[yus]

Hi,

there is an example using this function: https://root.cern/doc/master/CrystalBall_8C_source.html

[couet]

Better look at https://root.cern/doc/master/CrystalBall_8C.html
You will see the code and the graphics output produced by this macro.

[priyanshu-gif]

I am doing this but getting error so can you please help me with this ?

[priyanshu-gif]

With thisi am getting the error- undefined indetifier

[yus]

void crb()
{
        TCanvas* c1 = new TCanvas("c1", "my canvas", 0, 0, 800, 600);

        TF1 *myCrystallBall = new TF1("myCrystallBall", "ROOT::Math::crystalball_function(x, 2., 2., 1., 0.)", -3., +3.);
        TH1D* h1 = new TH1D("h1", "test1", 100, -3, +3);
        h1->FillRandom("myCrystallBall", 10000);
        h1->SetLineColor(kRed);
        h1->Draw();

        return;
}

[priyanshu-gif]

It is giving me this error and it is just creating canvas.so how can I correct this ?

[couet]

I guess @moneta might help.
But, can what do you get when you run exactly the example provided here: https://root.cern/doc/master/CrystalBall_8C.html
If you get errors it might be your ROOT version is not supporting this functionality.