RooFit generator

Roofit and RooStats
1

Dear experts,

I am trying to use RooFit generator to generate events on Dalitz plot.
As can be seen the plot attached.
There is a strange empty region near the edge which is not expected.

Btw looking at the output of the function value, the values in the empty place are similar to that of the other places.

By changing the options
RooAbsPdf::defaultGeneratorConfig()->getConfigSection(“RooFoamGenerator”).setRealValue(“nSample”,1e3);
RooAbsPdf::defaultGeneratorConfig()->getConfigSection(“RooFoamGenerator”).setRealValue(“nCell2D”,1e3);

The empty place moves from one place to another, but always exist.

Does anyone know what I should do in this case?

Many thanks
Wenbin

plot.png579×542 21 KB

2

I use finer binning (nsmaple and ncell2D) to solve the problem, the cost is much longer time to generate the events.

Thanks
Wenbin

3

Hi,

Is your pdf a RooHistPdf ? A similar problem is reported in

[A bug ?, extract a 2-D histogram based on Roofit

Lorenzo

4

Hi,

The problem is probably caused by the small level of nSamples. You can keep the default value of nCell2D, but increase nSamples to at least 10000

Lorenzo