def testCopysign(self):
self.assertEqual(math.copysign(1, 42), 1.0)
self.assertEqual(math.copysign(0., 42), 0.0)
self.assertEqual(math.copysign(1., -42), -1.0)
self.assertEqual(math.copysign(3, 0.), 3.0)
self.assertEqual(math.copysign(4., -0.), -4.0)
self.assertRaises(TypeError, math.copysign)
# copysign should let us distinguish signs of zeros
self.assertEqual(math.copysign(1., 0.), 1.)
self.assertEqual(math.copysign(1., -0.), -1.)
self.assertEqual(math.copysign(INF, 0.), INF)
self.assertEqual(math.copysign(INF, -0.), NINF)
self.assertEqual(math.copysign(NINF, 0.), INF)
self.assertEqual(math.copysign(NINF, -0.), NINF)
# and of infinities
self.assertEqual(math.copysign(1., INF), 1.)
self.assertEqual(math.copysign(1., NINF), -1.)
self.assertEqual(math.copysign(INF, INF), INF)
self.assertEqual(math.copysign(INF, NINF), NINF)
self.assertEqual(math.copysign(NINF, INF), INF)
self.assertEqual(math.copysign(NINF, NINF), NINF)
self.assertTrue(math.isnan(math.copysign(NAN, 1.)))
self.assertTrue(math.isnan(math.copysign(NAN, INF)))
self.assertTrue(math.isnan(math.copysign(NAN, NINF)))
self.assertTrue(math.isnan(math.copysign(NAN, NAN)))
# copysign(INF, NAN) may be INF or it may be NINF, since
# we don't know whether the sign bit of NAN is set on any
# given platform.
self.assertTrue(math.isinf(math.copysign(INF, NAN)))
# similarly, copysign(2., NAN) could be 2. or -2.
self.assertEqual(abs(math.copysign(2., NAN)), 2.)
def testCopysign(self):
self.assertEqual(math.copysign(1, 42), 1.0)
self.assertEqual(math.copysign(0., 42), 0.0)
self.assertEqual(math.copysign(1., -42), -1.0)
self.assertEqual(math.copysign(3, 0.), 3.0)
self.assertEqual(math.copysign(4., -0.), -4.0)
self.assertRaises(TypeError, math.copysign)
# copysign should let us distinguish signs of zeros
self.assertEqual(math.copysign(1., 0.), 1.)
self.assertEqual(math.copysign(1., -0.), -1.)
self.assertEqual(math.copysign(INF, 0.), INF)
self.assertEqual(math.copysign(INF, -0.), NINF)
self.assertEqual(math.copysign(NINF, 0.), INF)
self.assertEqual(math.copysign(NINF, -0.), NINF)
# and of infinities
self.assertEqual(math.copysign(1., INF), 1.)
self.assertEqual(math.copysign(1., NINF), -1.)
self.assertEqual(math.copysign(INF, INF), INF)
self.assertEqual(math.copysign(INF, NINF), NINF)
self.assertEqual(math.copysign(NINF, INF), INF)
self.assertEqual(math.copysign(NINF, NINF), NINF)
self.assertTrue(math.isnan(math.copysign(NAN, 1.)))
self.assertTrue(math.isnan(math.copysign(NAN, INF)))
self.assertTrue(math.isnan(math.copysign(NAN, NINF)))
self.assertTrue(math.isnan(math.copysign(NAN, NAN)))
# copysign(INF, NAN) may be INF or it may be NINF, since
# we don't know whether the sign bit of NAN is set on any
# given platform.
self.assertTrue(math.isinf(math.copysign(INF, NAN)))
# similarly, copysign(2., NAN) could be 2. or -2.
self.assertEqual(abs(math.copysign(2., NAN)), 2.)
def testIsinf(self):
self.assertTrue(math.isinf(float("inf")))
self.assertTrue(math.isinf(float("-inf")))
self.assertTrue(math.isinf(1E400))
self.assertTrue(math.isinf(-1E400))
self.assertFalse(math.isinf(float("nan")))
self.assertFalse(math.isinf(0.))
self.assertFalse(math.isinf(1.))
def testIsinf(self):
self.assert_(math.isinf(float("inf")))
self.assert_(math.isinf(float("-inf")))
self.assert_(math.isinf(1E400))
self.assert_(math.isinf(-1E400))
self.failIf(math.isinf(float("nan")))
self.failIf(math.isinf(0.))
self.failIf(math.isinf(1.))
def testIsinf(self):
self.assertTrue(math.isinf(float("inf")))
self.assertTrue(math.isinf(float("-inf")))
self.assertTrue(math.isinf(1E400))
self.assertTrue(math.isinf(-1E400))
self.assertFalse(math.isinf(float("nan")))
self.assertFalse(math.isinf(0.))
self.assertFalse(math.isinf(1.))
def testIsinf(self):
self.assert_(math.isinf(float("inf")))
self.assert_(math.isinf(float("-inf")))
self.assert_(math.isinf(1E400))
self.assert_(math.isinf(-1E400))
self.failIf(math.isinf(float("nan")))
self.failIf(math.isinf(0.))
self.failIf(math.isinf(1.))
def acc_check(expected, got, rel_err=2e-15, abs_err = 5e-323):
"""Determine whether non-NaN floats a and b are equal to within a
(small) rounding error. The default values for rel_err and
abs_err are chosen to be suitable for platforms where a float is
represented by an IEEE 754 double. They allow an error of between
9 and 19 ulps."""
# need to special case infinities, since inf - inf gives nan
if math.isinf(expected) and got == expected:
return None
error = got - expected
permitted_error = max(abs_err, rel_err * abs(expected))
if abs(error) < permitted_error:
return None
return "error = {}; permitted error = {}".format(error,
permitted_error)
def acc_check(expected, got, rel_err=2e-15, abs_err = 5e-323):
"""Determine whether non-NaN floats a and b are equal to within a
(small) rounding error. The default values for rel_err and
abs_err are chosen to be suitable for platforms where a float is
represented by an IEEE 754 double. They allow an error of between
9 and 19 ulps."""
# need to special case infinities, since inf - inf gives nan
if math.isinf(expected) and got == expected:
return None
error = got - expected
permitted_error = max(abs_err, rel_err * abs(expected))
if abs(error) < permitted_error:
return None
return "error = {}; permitted error = {}".format(error,
permitted_error)