lib-python.2.7.test.test_pow.py Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jython Show documentation
Show all versions of jython Show documentation
Jython is an implementation of the high-level, dynamic, object-oriented
language Python written in 100% Pure Java, and seamlessly integrated with
the Java platform. It thus allows you to run Python on any Java platform.
import test.test_support, unittest
class PowTest(unittest.TestCase):
def powtest(self, type):
if type != float:
for i in range(-1000, 1000):
self.assertEqual(pow(type(i), 0), 1)
self.assertEqual(pow(type(i), 1), type(i))
self.assertEqual(pow(type(0), 1), type(0))
self.assertEqual(pow(type(1), 1), type(1))
for i in range(-100, 100):
self.assertEqual(pow(type(i), 3), i*i*i)
pow2 = 1
for i in range(0,31):
self.assertEqual(pow(2, i), pow2)
if i != 30 : pow2 = pow2*2
for othertype in int, long:
for i in range(-10, 0) + range(1, 10):
ii = type(i)
for j in range(1, 11):
jj = -othertype(j)
pow(ii, jj)
for othertype in int, long, float:
for i in range(1, 100):
zero = type(0)
exp = -othertype(i/10.0)
if exp == 0:
continue
self.assertRaises(ZeroDivisionError, pow, zero, exp)
il, ih = -20, 20
jl, jh = -5, 5
kl, kh = -10, 10
asseq = self.assertEqual
if type == float:
il = 1
asseq = self.assertAlmostEqual
elif type == int:
jl = 0
elif type == long:
jl, jh = 0, 15
for i in range(il, ih+1):
for j in range(jl, jh+1):
for k in range(kl, kh+1):
if k != 0:
if type == float or j < 0:
self.assertRaises(TypeError, pow, type(i), j, k)
continue
asseq(
pow(type(i),j,k),
pow(type(i),j)% type(k)
)
def test_powint(self):
self.powtest(int)
def test_powlong(self):
self.powtest(long)
def test_powfloat(self):
self.powtest(float)
def test_other(self):
# Other tests-- not very systematic
self.assertEqual(pow(3,3) % 8, pow(3,3,8))
self.assertEqual(pow(3,3) % -8, pow(3,3,-8))
self.assertEqual(pow(3,2) % -2, pow(3,2,-2))
self.assertEqual(pow(-3,3) % 8, pow(-3,3,8))
self.assertEqual(pow(-3,3) % -8, pow(-3,3,-8))
self.assertEqual(pow(5,2) % -8, pow(5,2,-8))
self.assertEqual(pow(3L,3L) % 8, pow(3L,3L,8))
self.assertEqual(pow(3L,3L) % -8, pow(3L,3L,-8))
self.assertEqual(pow(3L,2) % -2, pow(3L,2,-2))
self.assertEqual(pow(-3L,3L) % 8, pow(-3L,3L,8))
self.assertEqual(pow(-3L,3L) % -8, pow(-3L,3L,-8))
self.assertEqual(pow(5L,2) % -8, pow(5L,2,-8))
for i in range(-10, 11):
for j in range(0, 6):
for k in range(-7, 11):
if j >= 0 and k != 0:
self.assertEqual(
pow(i,j) % k,
pow(i,j,k)
)
if j >= 0 and k != 0:
self.assertEqual(
pow(long(i),j) % k,
pow(long(i),j,k)
)
def test_bug643260(self):
class TestRpow:
def __rpow__(self, other):
return None
None ** TestRpow() # Won't fail when __rpow__ invoked. SF bug #643260.
def test_bug705231(self):
# -1.0 raised to an integer should never blow up. It did if the
# platform pow() was buggy, and Python didn't worm around it.
eq = self.assertEqual
a = -1.0
# The next two tests can still fail if the platform floor()
# function doesn't treat all large inputs as integers
# test_math should also fail if that is happening
eq(pow(a, 1.23e167), 1.0)
eq(pow(a, -1.23e167), 1.0)
for b in range(-10, 11):
eq(pow(a, float(b)), b & 1 and -1.0 or 1.0)
for n in range(0, 100):
fiveto = float(5 ** n)
# For small n, fiveto will be odd. Eventually we run out of
# mantissa bits, though, and thereafer fiveto will be even.
expected = fiveto % 2.0 and -1.0 or 1.0
eq(pow(a, fiveto), expected)
eq(pow(a, -fiveto), expected)
eq(expected, 1.0) # else we didn't push fiveto to evenness
def test_main():
test.test_support.run_unittest(PowTest)
if __name__ == "__main__":
test_main()