def test_division(self):
"""division should error when working with offset units"""
w = units.PhysicalQuantity('2kg')
x = units.PhysicalQuantity('1g')
y = units.PhysicalQuantity('2s')
z = units.PhysicalQuantity('1 degC')
quo = w.unit/x.unit
quo2 = x.unit/y.unit
self.assertEqual(quo,units.PhysicalUnit({'kg': 1, 'g': -1},
1000.0, _get_powers(),0))
self.assertEqual(quo2,units.PhysicalUnit({'s': -1, 'g': 1},
0.001,
_get_powers(mass=1, time=-1),0))
quo = y.unit/2.0
self.assertEqual(quo,units.PhysicalUnit({'s': 1, "2.0":-1},
.5, _get_powers(time=1), 0))
quo = 2.0/y.unit
self.assertEqual(quo,units.PhysicalUnit({'s': -1,"2.0":1},2,
_get_powers(time=-1),0))
try:
x.unit / z.unit
except TypeError,err:
self.assertEqual(str(err),"cannot divide units with non-zero offset")
def test_multiply(self):
"""multiplication should error for units with offsets"""
x = units.PhysicalQuantity('1g')
y = units.PhysicalQuantity('2s')
z = units.PhysicalQuantity('1 degC')
self.assertEqual(
x.unit * y.unit,
units.PhysicalUnit({
's': 1,
'kg': 1
}, .001, _get_powers(mass=1, time=1), 0))
self.assertEqual(
y.unit * x.unit,
units.PhysicalUnit({
's': 1,
'kg': 1
}, .001, _get_powers(mass=1, time=1), 0))
try:
x.unit * z.unit
except TypeError, err:
self.assertEqual(str(err),
"cannot multiply units with non-zero offset")