We present a Fortran code that contains the analytic ML-PDF described in our manuscript "Using analytic models to describe effective PDFs" (arXiv:2404.15175 [hep-ph]). This corresponds to an approximation to the PDFs obtained with LHAPDF6 using the HERAPDF20NLOEIG set. The main routine is HERAPDF_ML_simple(x, Q, PDF), which results from optimizing the coefficient functions described in Sec. 4 of our manuscript. The inputs are x (the momentum fraction) and Q (the factorization scale in GeV), with x in the range (1 E-4, 1) and Q in (1.47, 1000). The output is a 13-dimensional vector, PDF(-6:6) containing the PDF associated to the parton flavour i times x (the momentum fraction). Following the conventions of LHAPDF, i=0 is the gluon, i=1 down quark, i=2 up quark, i=3 strange quark, i=4 charm quark, i=5 bottom quark and -i represents the corresponding anti-quark. We are neglecting the top quark distribution (i=6).

It is worth appreciating that the methodology described in our manuscript can be applied to obtain analytic approximations to any PDF set. In the case of consideration, we manage to achieve a reduction of the computation time, keeping the errors under control (as described in the paper).

v2: Integral error of u and ubar distributions drastically reduced. Improved runtime reduction.