RooFFTConvPdf is not working for ROOT 6.30/02

[wwdws1]

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Description

When I use the RooFFTConvPdf function to convolved two pdf, there is an error infomation:

Error in <TVirtualFFT::FFT>: handler not found
Error in <TVirtualFFT::FFT>: handler not found
Error in <TVirtualFFT::FFT>: handler not found
[#0] FATAL:Eval -- RooFFTConvPdf::fillCacheSlice(sigpdfCannot get a handle to fftw. Maybe ROOT was built without it?
terminate called after throwing an instance of 'std::runtime_error'
  what():  Cannot get a handle to fftw.

But I have already installed all the dependencies include libfftw3-dev.

And I also try the same script under the ROOT 6.28/06, it works well.

Reproducer

A part of script:

    auto h1a = new TH1D("h1a", "h1a", nbins1, xlow1, xup1);
    t2->Draw("x>>h1a");

    RooDataHist exmch1a("exmch1a", "exmch1a", x, h1a, 1.0);

    RooHistPdf exmcpdf("exmcpdf", "exmcpdf", x, exmch1a, 0);

    RooRealVar mean_gauss("mean_gauss", "mean_gauss", 0.0, -10000.0, 10000.0);
    RooRealVar width_gauss("width_gauss", "width_gauss", 0.0, 0.0, 1000.0);
    RooGaussModel gausspdf("gausspdf", "gausspdf", x, mean_gauss, width_gauss);

    RooFFTConvPdf sigpdf("sigpdf", "sigpdf", x, exmcpdf, gausspdf);

I'm sorry I can't provide the rest of the script.

I run this script with the following command

root fit.cxx

ROOT version

ROOT 6.30/02

Installation method

pre-compiled binary

Operating system

Ubuntu 22.04

Additional context

No response

[guitargeek]

Hi @wwdws1, thanks for the report!

Unfortunately we had to take out the interface between ROOT and fftw3 out of the released binaries, because it was not license compatible with fftw3. Installing fftw3 doesn't help, because the relevant TVirtualFFT plugins won't be there.

I have suggested a solution to fix this for the next release:
#14174

[guitargeek]

Until we have solved this problem, you either have to use an older ROOT release prior to 6.30.00, or build root from source with -Dfftw3=ON.

[wwdws1]

Sorry for the late reply and thanks for your help. Now I am using the 6.28/06 and it works well.