Organisation of data files

The nnpdf++ code needs to be able to handle a great deal of different options with regard to the treatment of both experimental data and theoretical choices. In the code, every effort has been made to keep experimental and theoretical parameters strictly separate. In this section we shall specify the layout of the various nnpdf++ data directory. It is in this directory that all of the read-only data to be used in the fit are accessed. The data directory is located in the nnpdfcpp git repository, under the path /nnpdfcpp/data/.

Experimental data storage

The central repository for CommonData in use by nnpdf++ projects is located in the nnpdfcpp git repository at


where a separate CommonData file is stored for each Dataset with the filename format


Information on the treatment of systematic uncertainties, provided in SYSTYPE files, is located in the subdirectory


Here several SYSTYPE files may be supplied for each Dataset. The various options are enumerated by suffix to the filename. The filename format for SYSTYPE files is therefore


Where the default systematic ID is DEFAULT. As an example, consider the first SYSTYPE file for the D0ZRAP Dataset:


Theory lookup table

In order to organise the various different theoretical treatments available, a lookup table is provided in sqlite3 format. This lookup table can be found in the nnpdfcpp repository data directory at:


This file should only be edited in order to add new theory options. It may be edited with any appropriate sqlite3-supported software. A script is provided to give a brief overview of the various theory options available. It can be found at


and should be run without any arguments.

Theory options are enumerated by an integer TheoryID. The parameters of each theory option are described in the lookup table under the appropriate ID. The current available parameters are summarised in Theory parameter definitions.

Theory storage

Each theory configuration is stored as a gzip compressed tar archive with filename format


and is stored at the location specified in the default nnprofile.yaml. For easy access, they can be downloaded through the vp-get utility. Each archive contains the following directory structure


Inside the directory theory_X/cfactor/ are stored CFACTOR files with the filename format


where <TYP> is a three-letter designation for the source of the C-factor (e.g. EWK or QCD) and <SETNAME> is the typical Dataset designation. The directory theory_X/compound/ contains the COMPOUND files described earlier, this time with the filename format


Finally the FK tables themselves are stored in theory_X/fastkernel/ with the filename format


Naturally, all of the FastKernel and C-factor files within the directory theory_X/ have been determined with the theoretical parameters specified in the theory lookup table under ID X.