code: def plotgwsrc(gwb):
      
      theta, phi, omega, polarization = gwb.gw_dist()
  
      rho = phi-N.pi
      eta = 0.5*N.pi - theta
  
      # I don't know how to get rid of the RuntimeWarning -- RvH, Oct 10, 2014:
      #     /Users/vhaaster/env/dev/lib/python2.7/site-packages/matplotlib/projections/geo.py:485:
      #     RuntimeWarning: invalid value encountered in arcsin theta = np.arcsin(y / np.sqrt(2))
      #old_settings = N.seterr(invalid='ignore')
  
      P.title("GWB source population")
      ax = P.axes(projection='mollweide')
  
      foo = P.scatter(rho, eta, marker='.', s=1)
      #bar = N.seterr(**old_settings)
  
      return foo
docs: Plot a GWB source population as a mollweide projection.