diff --git a/Lib/test/test_strtod.py b/Lib/test/test_strtod.py index 0e67e8dcb6c..ea6b305c706 100644 --- a/Lib/test/test_strtod.py +++ b/Lib/test/test_strtod.py @@ -80,7 +80,7 @@ def strtod(s, mant_dig=53, min_exp = -1021, max_exp = 1024): hexdigs, e + 4*hexdigs) -TEST_SIZE = 16 +TEST_SIZE = 10 class StrtodTests(unittest.TestCase): def check_strtod(self, s): @@ -111,7 +111,7 @@ class StrtodTests(unittest.TestCase): lower = -(-2**53//5**k) if lower % 2 == 0: lower += 1 - for i in xrange(10 * TEST_SIZE): + for i in xrange(TEST_SIZE): # Select a random odd n in [2**53/5**k, # 2**54/5**k). Then n * 10**k gives a halfway case # with small number of significant digits. @@ -147,34 +147,29 @@ class StrtodTests(unittest.TestCase): def test_halfway_cases(self): # test halfway cases for the round-half-to-even rule - for i in xrange(1000): - for j in xrange(TEST_SIZE): - # bit pattern for a random finite positive (or +0.0) float - bits = random.randrange(2047*2**52) + for i in xrange(100 * TEST_SIZE): + # bit pattern for a random finite positive (or +0.0) float + bits = random.randrange(2047*2**52) - # convert bit pattern to a number of the form m * 2**e - e, m = divmod(bits, 2**52) - if e: - m, e = m + 2**52, e - 1 - e -= 1074 + # convert bit pattern to a number of the form m * 2**e + e, m = divmod(bits, 2**52) + if e: + m, e = m + 2**52, e - 1 + e -= 1074 - # add 0.5 ulps - m, e = 2*m + 1, e - 1 + # add 0.5 ulps + m, e = 2*m + 1, e - 1 - # convert to a decimal string - if e >= 0: - digits = m << e - exponent = 0 - else: - # m * 2**e = (m * 5**-e) * 10**e - digits = m * 5**-e - exponent = e - s = '{}e{}'.format(digits, exponent) - self.check_strtod(s) - - # get expected answer via struct, to triple check - #fs = struct.unpack('= 0: + digits = m << e + exponent = 0 + else: + # m * 2**e = (m * 5**-e) * 10**e + digits = m * 5**-e + exponent = e + s = '{}e{}'.format(digits, exponent) + self.check_strtod(s) def test_boundaries(self): # boundaries expressed as triples (n, e, u), where @@ -188,11 +183,10 @@ class StrtodTests(unittest.TestCase): ] for n, e, u in boundaries: for j in xrange(1000): - for i in xrange(TEST_SIZE): - digits = n + random.randrange(-3*u, 3*u) - exponent = e - s = '{}e{}'.format(digits, exponent) - self.check_strtod(s) + digits = n + random.randrange(-3*u, 3*u) + exponent = e + s = '{}e{}'.format(digits, exponent) + self.check_strtod(s) n *= 10 u *= 10 e -= 1 @@ -211,7 +205,7 @@ class StrtodTests(unittest.TestCase): def test_bigcomp(self): for ndigs in 5, 10, 14, 15, 16, 17, 18, 19, 20, 40, 41, 50: dig10 = 10**ndigs - for i in xrange(100 * TEST_SIZE): + for i in xrange(10 * TEST_SIZE): digits = random.randrange(dig10) exponent = random.randrange(-400, 400) s = '{}e{}'.format(digits, exponent)