code: def _compute_site_class_dummy_variables(cls, vs30):
          
          Sbc = np.zeros_like(vs30)
          Sc = np.zeros_like(vs30)
          Sd = np.zeros_like(vs30)
          Se = np.zeros_like(vs30)
  
          Sbc[vs30 > 760.] = 1
          Sc[(vs30 > 360) & (vs30 <= 760)] = 1
          Sd[(vs30 >= 180) & (vs30 <= 360)] = 1
          Se[vs30 < 180] = 1
  
          return Sbc, Sc, Sd, Se
docs: Extend
          :meth:`AtkinsonBoore2003SInter._compute_site_class_dummy_variables`
          and includes dummy variable for B/C site conditions (vs30 > 760.)