def test_known_values(self):
t1 = Temperature()
t2 = Temperature()
t3 = Temperature()
t4 = Temperature()
for K, R, C, F in self.known_values:
t1['K'] = K
self.assertAlmostEqual(t1['K'], K)
self.assertAlmostEqual(t1['R'], R)
self.assertAlmostEqual(t1['C'], C)
self.assertAlmostEqual(t1['F'], F)
t2['R'] = R
self.assertAlmostEqual(t2['K'], K)
self.assertAlmostEqual(t2['R'], R)
self.assertAlmostEqual(t2['C'], C)
self.assertAlmostEqual(t2['F'], F)
t3['C'] = C
self.assertAlmostEqual(t3['K'], K)
self.assertAlmostEqual(t3['R'], R)
self.assertAlmostEqual(t3['C'], C)
self.assertAlmostEqual(t3['F'], F)
t4['F'] = F
self.assertAlmostEqual(t4['K'], K)
self.assertAlmostEqual(t4['R'], R)
self.assertAlmostEqual(t4['C'], C)
self.assertAlmostEqual(t4['F'], F)
def test_str(self):
"""str() prints a reasonable form for the quantity."""
# dimensionless case
p = PhysicalQuantity(Dimension(), "2.1e2")
self.assertEqual(str(p), "210")
# For quantities that are NOT dimensionless we use the "basic unit" (whatever has a unit conversion
# factor, so it's SI in our case) with the shortest string representation.
# Also, in both the numerator and denominator the order followed is M L T Q Theta
p = Speed("60 km/min")
self.assertEqual(str(p), "1000 m/s")
p = PhysicalQuantity(Dimension(Q = 1), "4 coulomb")
self.assertEqual(str(p), "4 C")
p = Temperature("4 kelvin")
self.assertEqual(str(p), "4 K")
p = Speed("30m/s")/Time("2s")/PhysicalQuantity(Dimension(M = 1), "3kg")
self.assertEqual(str(p), "5 m/kgs^2")
def test_type_guessing_in_general(self):
"""The library should find the proper type depending on dimensions."""
d = Distance("10m")
t = Time("5s")
self.assertEqual(type(d/t), Speed)
v = Speed("10mi/hr")
self.assertEqual(type(v*t), Distance)
# charge density
rho = PhysicalQuantity(Dimension(L = -3, Q = 1), "4C/m^3")
q = rho*d*d*d
self.assertEqual(type(q), Charge)
self.assertEqual(q['C'], 4000)
# Note: this doesn't work for a quantity explicitly defined as a PhysicalQuantity
T1 = Temperature("3 K")
T2 = PhysicalQuantity(Dimension(Theta = 1), "3 K")
self.assertEqual(T1, T2)
self.assertEqual(type(T1), Temperature)
self.assertEqual(type(T2), PhysicalQuantity)
# But a multiplication or division by a dimensionless quantity should fix that
T3 = T2/PhysicalQuantity(Dimension(), "1")
self.assertEqual(type(T3), Temperature)
def test_consistency(self):
"""In its own units, the value should be 1."""
for unit in self.kelvins_in.keys():
t = Temperature('1' + unit) # create "1x" where x is the unit
self.assertEqual(t[unit], 1)
def test_create_simple_temperatures(self):
"""Simple temperatures."""
for unit,kelvins in self.kelvins_in.iteritems():
t = Temperature('1' + unit) # create "1x" where x is the unit
self.assertEqual(t['K'], kelvins)