Problem with FFTW

[antares01]

Hi all!
I’m trying to use RootFit to perform a fit using a convolution between a Landau distribution and a gaussian.
In order to do the convolution, I use RooFFTConvPdf:

RooFFTConvPdf conv("conv", "Landau convoluted with Gaussian", x, landau, gauss);

(with landau and gauss previously defined).

When I try to execute the code, I get the following error message:

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(convCannot get a handle to fftw. Maybe ROOT was built without it?
libc++abi: terminating due to uncaught exception of type std::runtime_error: Cannot get a handle to fftw.

Typing brew list | grep fftw I get fftw: so it looks like fftw is properly installed.

Does anyone know what the problem is? How can I solve it?
I’m using a MacBook and I have installed ROOT with Homebrew.

Thanks a lot

[Danilo]

Hi,

Sorry to read ROOT did not work for you out of the box in this case. We could be dealing with some kind of misconfiguration.

What version of ROOT is this and on what platform?

Cheers,
Danilo

[antares01]

Hi Danilo,

My ROOT version is 6.28/04, and it’s installed on macosxarm64.

Thanks a lot for looking into this!

[Danilo]

Hi,

Thanks for the info. It’s not a recent release, but that should not count much in this context.
Could you please check the configuration features of your installation and if fftw3 is included? You can do it like this, at the prompt:

root [0] gROOT->GetConfigFeatures()
(const char *) "cxx17  arrow asimage builtin_afterimage builtin_clang builtin_cling builtin_llvm builtin_openui5 dataframe davix dcache fftw3 fitsio fortran gdml gnuinstall gviz http fcgi imt mathmore mysql odbc opengl pgsql proof pyroot pythia8 qt5web qt6web r roofit webgui root7 shadowpw shared soversion sqlite ssl tmva tmva-cpu tmva-sofie tmva-pymva tmva-rmva spectrum unfold unuran x11 xml xrootd"
root [1] strstr(gROOT->GetConfigFeatures(), "fftw3")
(const char *) "fftw3 fitsio fortran gdml gnuinstall gviz http fcgi imt mathmore mysql odbc opengl pgsql proof pyroot pythia8 qt5web qt6web r roofit webgui root7 shadowpw shared soversion sqlite ssl tmva tmva-cpu tmva-sofie tmva-pymva tmva-rmva spectrum unfold unuran x11 xml xrootd"

Do you see fftw3?

Cheers,
D

[antares01]

Hi,

I tried and definitely couldn’t see fftw3:

root [0] gROOT->GetConfigFeatures()
(const char *) "cxx17  asimage builtin_afterimage builtin_clang builtin_cling builtin_freetype builtin_ftgl builtin_glew builtin_gtest builtin_llvm builtin_nlohmannjson builtin_openui5 builtin_unuran builtin_zlib clad cocoa dataframe davix exceptions fortran gdml gnuinstall gsl_shared gviz http imt libcxx mathmore mlp minuit2 opengl pyroot roofit webgui root7 rpath shared soversion ssl tmva tmva-cpu tmva-pymva spectrum unuran vdt xml xrootd"
root [1] strstr(gROOT->GetConfigFeatures(), "fftw3")
(const char *) nullptr

What does it mean? What do I need to do?

Thanks a lot again

[Danilo]

Hi,

Could you please try 6.32.08? From the brew formula, it should be there (and that’s the latest stable release)

Cheers,
D

[antares01]

Hi,

I updated ROOT and now I have version 6.32.08.
I tried to run my code but the same error message occurs.
But I tried again root [0] gROOT->GetConfigFeatures() and root [1] strstr(gROOT->GetConfigFeatures(), "fftw3"):

root [0] gROOT->GetConfigFeatures()
(const char *) "cxx17  asimage builtin_afterimage builtin_clang builtin_cling builtin_freetype builtin_llvm builtin_openui5 builtin_vdt clad cocoa dataframe davix fftw3 fitsio fortran gdml gnuinstall http imt libcxx mathmore mysql opengl pyroot roofit webgui root7 rpath runtime_cxxmodules shared sqlite ssl tmva tmva-cpu tmva-pymva spectrum vdt xml xrootd"
root [1] strstr(gROOT->GetConfigFeatures(), "fftw3")
(const char *) "fftw3 fitsio fortran gdml gnuinstall http imt libcxx mathmore mysql opengl pyroot roofit webgui root7 rpath runtime_cxxmodules shared sqlite ssl tmva tmva-cpu tmva-pymva spectrum vdt xml xrootd"

and at least now I can see fftw3.
What can I do now?

Thanks a lot!