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			251 lines
		
	
	
	
		
			9.4 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
		
		
			
		
	
	
			251 lines
		
	
	
	
		
			9.4 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
|   | # 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) |