code: def _compute_mean(self, C, rup, dists, sites, imt):
          
          # Convert rhypo to rrup
          rrup = rhypo_to_rrup(dists.rhypo, rup.mag)
          mean = (self._get_magnitude_scaling_term(C, rup.mag) +
                  self._get_distance_scaling_term(C, rup.mag, rrup) +
                  self._get_style_of_faulting_term(C, rup.rake) +
                  self._get_site_amplification_term(C, sites.vs30))
          # convert from cm/s**2 to g for SA and from cm/s**2 to g for PGA (PGV
          # is already in cm/s) and also convert from base 10 to base e.
          if isinstance(imt, PGA):
              mean = np.log((10 ** mean) * ((2 * np.pi / 0.01) ** 2) *
                            1e-2 / g)
          elif isinstance(imt, SA):
              mean = np.log((10 ** mean) * ((2 * np.pi / imt.period) ** 2) *
                            1e-2 / g)
          else:
              mean = np.log(10 ** mean)
  
          return mean + self.adjustment_factor
docs: Returns the mean ground motion acceleration and velocity