def test_scaling_and_assignment(self):
handler1 = TestUnitHandler1(self.a)
handler2 = NestUnitHandler(self.a)
self.assertEqual(handler1.scale_alias('A2'),
(Expression('ARP2 + P3'), 'ms*nA'))
self.assertEqual(handler1.scale_alias('A4'),
(Expression('ARP3 + 100/(P2*P6)'), 'S/cm2'))
self.assertEqual(handler1.scale_alias('A5'),
(Expression('P7 * P8'), 'mV'))
self.assertEqual(handler1.scale_alias('A6'),
(Expression('1e-3 * P9/P10'), 'ms'))
self.assertEqual(
handler2.scale_time_derivative(self.a.regime('R1').element('SV2')),
(Expression('C1 * SV2 ** 2 + C2 * SV2 + C3 + SV3 + '
'ARP4 / P11'), 'mV/ms'))
self.assertEqual(
handler2.scale_time_derivative(self.a.regime('R1').element('SV3')),
(Expression('P12*(SV2*P13 - SV3)'), 'mV/ms^2'))
self.assertEqual(handler1.assign_units_to_variable('P2'), '1/uS')
self.assertEqual(handler1.assign_units_to_variable('P6'), 'um^2')
