Added a new example that adds Neptune and Pluto to a Helio run. I had to do a lot of maintenence on the initial conditions generators in the Python side of things in order to get it to generate properly

examples/helio_neptune_pluto/init_cond.py

@@ -0,0 +1,42 @@
+#!/usr/bin/env python3
+import swiftest
+
+sim = swiftest.Simulation()
+sim.param['IN_TYPE'] = "NETCDF_DOUBLE"
+sim.param['NC_IN'] = "init_cond.nc"
+sim.param['IN_FORM'] = "XV"
+sim.param['BIN_OUT'] = "bin.nc"
+sim.param['OUT_FORM'] = "XVEL"
+sim.param['OUT_TYPE'] = "NETCDF_DOUBLE"
+
+sim.param['MU2KG'] = swiftest.MSun
+sim.param['TU2S'] = swiftest.YR2S
+sim.param['DU2M'] = swiftest.AU2M
+sim.param['T0'] = 0.0
+sim.param['DT'] = 5.0 
+sim.param['TSTOP'] = 1.e5
+sim.param['ISTEP_OUT']  = 100
+sim.param['ISTEP_DUMP'] = 100
+sim.param['CHK_QMIN_COORD'] = "HELIO"
+sim.param['CHK_QMIN'] = swiftest.RSun / swiftest.AU2M
+sim.param['CHK_QMIN_RANGE'] = f"{swiftest.RSun / swiftest.AU2M} 1000.0"
+sim.param['CHK_RMIN'] = swiftest.RSun / swiftest.AU2M
+sim.param['CHK_RMAX'] = 1000.0
+sim.param['CHK_EJECT'] = 1000.0
+sim.param['OUT_STAT'] = "REPLACE"
+sim.param['RHILL_PRESENT'] = "NO"
+sim.param['GR'] = 'NO'
+sim.param['CHK_CLOSE'] = "NO"
+
+bodyid = {
+   "Sun": 0,
+   "Neptune": 8,
+   "Pluto" : 9
+}
+
+for name, id in bodyid.items():
+   sim.add(name, idval=id, date="2027-04-30")
+
+sim.save("param.in")
+
+