def testto_from_element(self):
element = self.ops.toelement()
obj = Options.fromelement(element)
self.assertEqual(1, len(obj.programs))
self.assertAlmostEqual(1234, obj.beam.energy_eV, 4)
self.assertEqual(1, len(obj.detectors))
det = obj.detectors['bse']
self.assertAlmostEqual(0, det.limits_eV[0], 4)
self.assertAlmostEqual(1234, det.limits_eV[1], 4)
self.assertEqual(1000, det.channels)
self.assertEqual(1, len(obj.limits))
limits = list(obj.limits.iterclass(ShowersLimit))
self.assertEqual(1, len(limits))
self.assertEqual(5678, limits[0].showers)
self.assertEqual(1, len(obj.models))
models = list(obj.models.iterclass(ELASTIC_CROSS_SECTION))
self.assertEqual(1, len(models))
self.assertEqual(ELASTIC_CROSS_SECTION.rutherford, models[0])
