code: def targetSurfacemassLOS(self,d,l,log=False,deg=True):
          
          #Calculate R and phi
          if _APY_LOADED and isinstance(l,units.Quantity):
              lrad= l.to(units.rad).value
          elif deg:
              lrad= l*_DEGTORAD
          else:
              lrad= l
          if _APY_LOADED and isinstance(d,units.Quantity):
              d= d.to(units.kpc).value/self._ro
          R, phi= _dlToRphi(d,lrad)
          if log:
              return self._surfaceSigmaProfile.surfacemass(R,log=log)\
                  +math.log(d)
          else:
              return self._surfaceSigmaProfile.surfacemass(R,log=log)\
                  *d
docs: NAME:
  
              targetSurfacemassLOS
  
          PURPOSE:
  
              evaluate the target surface mass along the LOS given l and d
  
          INPUT:
  
              d - distance along the line of sight (can be Quantity)
  
              l - Galactic longitude (in deg, unless deg=False; can be Quantity)
  
              deg= if False, l is in radians
  
              log - if True, return the log (default: False)
  
          OUTPUT:
  
              Sigma(d,l) x d
  
          HISTORY:
  
              2011-03-23 - Written - Bovy (NYU)