diff options
Diffstat (limited to 'Lib/test/test_math.py')
| -rw-r--r-- | Lib/test/test_math.py | 104 |
1 files changed, 65 insertions, 39 deletions
diff --git a/Lib/test/test_math.py b/Lib/test/test_math.py index dddc889375..48f84ba732 100644 --- a/Lib/test/test_math.py +++ b/Lib/test/test_math.py @@ -2,11 +2,12 @@ # XXXX Should not do tests around zero only from test.support import run_unittest, verbose, requires_IEEE_754 +from test import support import unittest import math import os +import platform import sys -import random import struct import sysconfig @@ -457,12 +458,12 @@ class MathTests(unittest.TestCase): def testFmod(self): self.assertRaises(TypeError, math.fmod) - self.ftest('fmod(10,1)', math.fmod(10,1), 0) - self.ftest('fmod(10,0.5)', math.fmod(10,0.5), 0) - self.ftest('fmod(10,1.5)', math.fmod(10,1.5), 1) - self.ftest('fmod(-10,1)', math.fmod(-10,1), 0) - self.ftest('fmod(-10,0.5)', math.fmod(-10,0.5), 0) - self.ftest('fmod(-10,1.5)', math.fmod(-10,1.5), -1) + self.ftest('fmod(10, 1)', math.fmod(10, 1), 0.0) + self.ftest('fmod(10, 0.5)', math.fmod(10, 0.5), 0.0) + self.ftest('fmod(10, 1.5)', math.fmod(10, 1.5), 1.0) + self.ftest('fmod(-10, 1)', math.fmod(-10, 1), -0.0) + self.ftest('fmod(-10, 0.5)', math.fmod(-10, 0.5), -0.0) + self.ftest('fmod(-10, 1.5)', math.fmod(-10, 1.5), -1.0) self.assertTrue(math.isnan(math.fmod(NAN, 1.))) self.assertTrue(math.isnan(math.fmod(1., NAN))) self.assertTrue(math.isnan(math.fmod(NAN, NAN))) @@ -650,6 +651,33 @@ class MathTests(unittest.TestCase): n= 2**90 self.assertAlmostEqual(math.log1p(n), math.log1p(float(n))) + @requires_IEEE_754 + def testLog2(self): + self.assertRaises(TypeError, math.log2) + + # Check some integer values + self.assertEqual(math.log2(1), 0.0) + self.assertEqual(math.log2(2), 1.0) + self.assertEqual(math.log2(4), 2.0) + + # Large integer values + self.assertEqual(math.log2(2**1023), 1023.0) + self.assertEqual(math.log2(2**1024), 1024.0) + self.assertEqual(math.log2(2**2000), 2000.0) + + self.assertRaises(ValueError, math.log2, -1.5) + self.assertRaises(ValueError, math.log2, NINF) + self.assertTrue(math.isnan(math.log2(NAN))) + + @requires_IEEE_754 + # log2() is not accurate enough on Mac OS X Tiger (10.4) + @support.requires_mac_ver(10, 5) + def testLog2Exact(self): + # Check that we get exact equality for log2 of powers of 2. + actual = [math.log2(math.ldexp(1.0, n)) for n in range(-1074, 1024)] + expected = [float(n) for n in range(-1074, 1024)] + self.assertEqual(actual, expected) + def testLog10(self): self.assertRaises(TypeError, math.log10) self.ftest('log10(0.1)', math.log10(0.1), -1) @@ -952,38 +980,37 @@ class MathTests(unittest.TestCase): # still fails this part of the test on some platforms. For now, we only # *run* test_exceptions() in verbose mode, so that this isn't normally # tested. + @unittest.skipUnless(verbose, 'requires verbose mode') + def test_exceptions(self): + try: + x = math.exp(-1000000000) + except: + # mathmodule.c is failing to weed out underflows from libm, or + # we've got an fp format with huge dynamic range + self.fail("underflowing exp() should not have raised " + "an exception") + if x != 0: + self.fail("underflowing exp() should have returned 0") + + # If this fails, probably using a strict IEEE-754 conforming libm, and x + # is +Inf afterwards. But Python wants overflows detected by default. + try: + x = math.exp(1000000000) + except OverflowError: + pass + else: + self.fail("overflowing exp() didn't trigger OverflowError") - if verbose: - def test_exceptions(self): - try: - x = math.exp(-1000000000) - except: - # mathmodule.c is failing to weed out underflows from libm, or - # we've got an fp format with huge dynamic range - self.fail("underflowing exp() should not have raised " - "an exception") - if x != 0: - self.fail("underflowing exp() should have returned 0") - - # If this fails, probably using a strict IEEE-754 conforming libm, and x - # is +Inf afterwards. But Python wants overflows detected by default. - try: - x = math.exp(1000000000) - except OverflowError: - pass - else: - self.fail("overflowing exp() didn't trigger OverflowError") - - # If this fails, it could be a puzzle. One odd possibility is that - # mathmodule.c's macros are getting confused while comparing - # Inf (HUGE_VAL) to a NaN, and artificially setting errno to ERANGE - # as a result (and so raising OverflowError instead). - try: - x = math.sqrt(-1.0) - except ValueError: - pass - else: - self.fail("sqrt(-1) didn't raise ValueError") + # If this fails, it could be a puzzle. One odd possibility is that + # mathmodule.c's macros are getting confused while comparing + # Inf (HUGE_VAL) to a NaN, and artificially setting errno to ERANGE + # as a result (and so raising OverflowError instead). + try: + x = math.sqrt(-1.0) + except ValueError: + pass + else: + self.fail("sqrt(-1) didn't raise ValueError") @requires_IEEE_754 def test_testfile(self): @@ -1010,7 +1037,6 @@ class MathTests(unittest.TestCase): @requires_IEEE_754 def test_mtestfile(self): - ALLOWED_ERROR = 20 # permitted error, in ulps fail_fmt = "{}:{}({!r}): expected {!r}, got {!r}" failures = [] |