The evolution of the global stellar mass function of star clusters: an
  analytic description
  The evolution of the global stellar mass function (MF) of star clusters is
studied based on a large set of N-body simulations of clusters with a range of
initial masses, initial concentrations, in circular or elliptical orbits in
different tidal environments. Models with and without initial mass segregation
are included. The depletion of low mass stars in initially Roche-volume (tidal)
filling clusters starts typically on a time scale of the order of the core
collapse time. In clusters that are initially underfilling their Roche-volume
it takes longer because the clusters have to expand to their tidal radii before
dynamical mass loss becomes important.
  We introduce the concept of the differential mass function (DMF), which
describes the changes with respect to the initial mass function (IMF). We show
that the evolution of the DMF can be described by a set of very simple analytic
expressions that are valid for a wide range of initial cluster parameters and
for different IMFs. The agreement between this description and the models is
very good, except for initially Roche-volume underfilling clusters that are
severely mass segregated.
