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Diffstat (limited to 'Modules/_decimal/tests/randfloat.py')
| -rw-r--r-- | Modules/_decimal/tests/randfloat.py | 250 |
1 files changed, 0 insertions, 250 deletions
diff --git a/Modules/_decimal/tests/randfloat.py b/Modules/_decimal/tests/randfloat.py deleted file mode 100644 index 1687303..0000000 --- a/Modules/_decimal/tests/randfloat.py +++ /dev/null @@ -1,250 +0,0 @@ -# Copyright (c) 2010 Python Software Foundation. All Rights Reserved. -# Adapted from Python's Lib/test/test_strtod.py (by Mark Dickinson) - -# More test cases for deccheck.py. - -import random - -TEST_SIZE = 2 - - -def test_short_halfway_cases(): - # exact halfway cases with a small number of significant digits - for k in 0, 5, 10, 15, 20: - # upper = smallest integer >= 2**54/5**k - upper = -(-2**54//5**k) - # lower = smallest odd number >= 2**53/5**k - lower = -(-2**53//5**k) - if lower % 2 == 0: - lower += 1 - for i in range(10 * 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. - n, e = random.randrange(lower, upper, 2), k - - # Remove any additional powers of 5. - while n % 5 == 0: - n, e = n // 5, e + 1 - assert n % 10 in (1, 3, 7, 9) - - # Try numbers of the form n * 2**p2 * 10**e, p2 >= 0, - # until n * 2**p2 has more than 20 significant digits. - digits, exponent = n, e - while digits < 10**20: - s = '{}e{}'.format(digits, exponent) - yield s - # Same again, but with extra trailing zeros. - s = '{}e{}'.format(digits * 10**40, exponent - 40) - yield s - digits *= 2 - - # Try numbers of the form n * 5**p2 * 10**(e - p5), p5 - # >= 0, with n * 5**p5 < 10**20. - digits, exponent = n, e - while digits < 10**20: - s = '{}e{}'.format(digits, exponent) - yield s - # Same again, but with extra trailing zeros. - s = '{}e{}'.format(digits * 10**40, exponent - 40) - yield s - digits *= 5 - exponent -= 1 - -def test_halfway_cases(): - # test halfway cases for the round-half-to-even rule - for i in range(1000): - for j in range(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 - - # 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) - yield s - -def test_boundaries(): - # boundaries expressed as triples (n, e, u), where - # n*10**e is an approximation to the boundary value and - # u*10**e is 1ulp - boundaries = [ - (10000000000000000000, -19, 1110), # a power of 2 boundary (1.0) - (17976931348623159077, 289, 1995), # overflow boundary (2.**1024) - (22250738585072013831, -327, 4941), # normal/subnormal (2.**-1022) - (0, -327, 4941), # zero - ] - for n, e, u in boundaries: - for j in range(1000): - for i in range(TEST_SIZE): - digits = n + random.randrange(-3*u, 3*u) - exponent = e - s = '{}e{}'.format(digits, exponent) - yield s - n *= 10 - u *= 10 - e -= 1 - -def test_underflow_boundary(): - # test values close to 2**-1075, the underflow boundary; similar - # to boundary_tests, except that the random error doesn't scale - # with n - for exponent in range(-400, -320): - base = 10**-exponent // 2**1075 - for j in range(TEST_SIZE): - digits = base + random.randrange(-1000, 1000) - s = '{}e{}'.format(digits, exponent) - yield s - -def test_bigcomp(): - for ndigs in 5, 10, 14, 15, 16, 17, 18, 19, 20, 40, 41, 50: - dig10 = 10**ndigs - for i in range(100 * TEST_SIZE): - digits = random.randrange(dig10) - exponent = random.randrange(-400, 400) - s = '{}e{}'.format(digits, exponent) - yield s - -def test_parsing(): - # make '0' more likely to be chosen than other digits - digits = '000000123456789' - signs = ('+', '-', '') - - # put together random short valid strings - # \d*[.\d*]?e - for i in range(1000): - for j in range(TEST_SIZE): - s = random.choice(signs) - intpart_len = random.randrange(5) - s += ''.join(random.choice(digits) for _ in range(intpart_len)) - if random.choice([True, False]): - s += '.' - fracpart_len = random.randrange(5) - s += ''.join(random.choice(digits) - for _ in range(fracpart_len)) - else: - fracpart_len = 0 - if random.choice([True, False]): - s += random.choice(['e', 'E']) - s += random.choice(signs) - exponent_len = random.randrange(1, 4) - s += ''.join(random.choice(digits) - for _ in range(exponent_len)) - - if intpart_len + fracpart_len: - yield s - -test_particular = [ - # squares - '1.00000000100000000025', - '1.0000000000000000000000000100000000000000000000000' #... - '00025', - '1.0000000000000000000000000000000000000000000010000' #... - '0000000000000000000000000000000000000000025', - '1.0000000000000000000000000000000000000000000000000' #... - '000001000000000000000000000000000000000000000000000' #... - '000000000025', - '0.99999999900000000025', - '0.9999999999999999999999999999999999999999999999999' #... - '999000000000000000000000000000000000000000000000000' #... - '000025', - '0.9999999999999999999999999999999999999999999999999' #... - '999999999999999999999999999999999999999999999999999' #... - '999999999999999999999999999999999999999990000000000' #... - '000000000000000000000000000000000000000000000000000' #... - '000000000000000000000000000000000000000000000000000' #... - '0000000000000000000000000000025', - - '1.0000000000000000000000000000000000000000000000000' #... - '000000000000000000000000000000000000000000000000000' #... - '100000000000000000000000000000000000000000000000000' #... - '000000000000000000000000000000000000000000000000001', - '1.0000000000000000000000000000000000000000000000000' #... - '000000000000000000000000000000000000000000000000000' #... - '500000000000000000000000000000000000000000000000000' #... - '000000000000000000000000000000000000000000000000005', - '1.0000000000000000000000000000000000000000000000000' #... - '000000000100000000000000000000000000000000000000000' #... - '000000000000000000250000000000000002000000000000000' #... - '000000000000000000000000000000000000000000010000000' #... - '000000000000000000000000000000000000000000000000000' #... - '0000000000000000001', - '1.0000000000000000000000000000000000000000000000000' #... - '000000000100000000000000000000000000000000000000000' #... - '000000000000000000249999999999999999999999999999999' #... - '999999999999979999999999999999999999999999999999999' #... - '999999999999999999999900000000000000000000000000000' #... - '000000000000000000000000000000000000000000000000000' #... - '00000000000000000000000001', - - '0.9999999999999999999999999999999999999999999999999' #... - '999999999900000000000000000000000000000000000000000' #... - '000000000000000000249999999999999998000000000000000' #... - '000000000000000000000000000000000000000000010000000' #... - '000000000000000000000000000000000000000000000000000' #... - '0000000000000000001', - '0.9999999999999999999999999999999999999999999999999' #... - '999999999900000000000000000000000000000000000000000' #... - '000000000000000000250000001999999999999999999999999' #... - '999999999999999999999999999999999990000000000000000' #... - '000000000000000000000000000000000000000000000000000' #... - '1', - - # tough cases for ln etc. - '1.000000000000000000000000000000000000000000000000' #... - '00000000000000000000000000000000000000000000000000' #... - '00100000000000000000000000000000000000000000000000' #... - '00000000000000000000000000000000000000000000000000' #... - '0001', - '0.999999999999999999999999999999999999999999999999' #... - '99999999999999999999999999999999999999999999999999' #... - '99899999999999999999999999999999999999999999999999' #... - '99999999999999999999999999999999999999999999999999' #... - '99999999999999999999999999999999999999999999999999' #... - '9999' - ] - - -TESTCASES = [ - [x for x in test_short_halfway_cases()], - [x for x in test_halfway_cases()], - [x for x in test_boundaries()], - [x for x in test_underflow_boundary()], - [x for x in test_bigcomp()], - [x for x in test_parsing()], - test_particular -] - -def un_randfloat(): - for i in range(1000): - l = random.choice(TESTCASES[:6]) - yield random.choice(l) - for v in test_particular: - yield v - -def bin_randfloat(): - for i in range(1000): - l1 = random.choice(TESTCASES) - l2 = random.choice(TESTCASES) - yield random.choice(l1), random.choice(l2) - -def tern_randfloat(): - for i in range(1000): - l1 = random.choice(TESTCASES) - l2 = random.choice(TESTCASES) - l3 = random.choice(TESTCASES) - yield random.choice(l1), random.choice(l2), random.choice(l3) |