This code allows to numerically evaluate the results presented in:
  S. Catani, S. Devoto, M. Grazzini and J. Mazzitelli,
  "Soft-parton contributions to heavy-quark production at low transverse momentum"

Some of the analytic results are expressed in terms of HPLs, which are
evaluated using the CHAPLIN library. Partial results are provided in the shape
of 2-dimensional grids, which are fitted using the DIERCKX package (the relevant files
for the splines fitting are included)

In order to compile the example:

1) Download and install CHAPLIN (https://chaplin.hepforge.org/)
   Update the Makefile with the corresponding path to the CHAPLIN library

2) Compile by doing 'make'

The main file can be found in src/main.f
It computes for a given value of beta, cost and nf all the non-vanishing contributions
to h1 and h2, split into the different colour structures. Specifically, the functions
that are defined are:

h1_TT(i,j) -----------> term in h^(1) proportional to Ti.Tj
h2_TT(i,j) -----------> term in h^(2) proportional to Ti.Tj
h2_TTTT(i,j,k,l) -----> term in h^(2) proportional to Ti.Tj Tk.Tl

which correspond to the quantities in Eq.(304) of the paper