code: def integrate(self,t,pot,method='symplec4_c',dt=None):
          
          if hasattr(self,'_orbInterp'): delattr(self,'_orbInterp')
          if hasattr(self,'rs'): delattr(self,'rs')
          thispot= toPlanarPotential(pot)
          self.t= nu.array(t)
          self._pot= thispot
          self.orbit, msg= _integrateOrbit(self.vxvv,thispot,t,method,dt)
          return msg
docs: NAME:
             integrate
          PURPOSE:
             integrate the orbit
          INPUT:
             t - list of times at which to output (0 has to be in this!)
             pot - potential instance or list of instances
             method= 'odeint' for scipy's odeint
                     'leapfrog' for a simple leapfrog implementation
                     'leapfrog_c' for a simple leapfrog implementation in C
                     'rk4_c' for a 4th-order Runge-Kutta integrator in C
                     'rk6_c' for a 6-th order Runge-Kutta integrator in C
                     'dopr54_c' for a Dormand-Prince integrator in C (generally the fastest)
             dt= (None) if set, force the integrator to use this basic stepsize; must be an integer divisor of output stepsize
          OUTPUT:
             (none) (get the actual orbit using getOrbit()
          HISTORY:
             2010-07-20