def byte_arrays_of_floats(draw):
num_items = draw(st.integers(min_value=0, max_value=10))
floats = draw(st.lists(ibm_compatible_floats(),
min_size=num_items,
max_size=num_items))
byte_data = b''.join([ieee2ibm(f) for f in floats])
return (byte_data, num_items)
def byte_arrays_of_floats(draw):
num_items = draw(st.integers(min_value=0, max_value=10))
floats = draw(
st.lists(ibm_compatible_floats(),
min_size=num_items,
max_size=num_items))
byte_data = b''.join([ieee2ibm(f) for f in floats])
return (byte_data, num_items)
def test_zero(self):
self.assertEqual(ieee2ibm(0.0), b'\0\0\0\0')
def test_zero(self):
ibm_start = b'\0\0\0\0'
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
assert ibm_start == ibm_result
def test_one(self):
assert ieee2ibm(1.0) == b'\x41\x10\x00\x00'
def test_one(self):
assert ieee2ibm(1.0) == b'\x41\x10\x00\x00'
def test_smallest_subnormal(self):
assert ieee2ibm(5.147557589468029e-85) == bytes((0x00, 0x00, 0x00, 0x01))
def test_subnormal(self):
self.assertEqual(ieee2ibm(1.6472184286297693e-83), bytes((0x00, 0x00, 0x00, 0x20)))
def test_inf(self):
with self.assertRaises(ValueError):
ieee2ibm(float('inf'))
def test_zero(self):
ibm_start = b'\0\0\0\0'
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
assert ibm_start == ibm_result
def test_positive_half(self):
ibm_start = bytes((0b11000000, 0x80, 0x00, 0x00))
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
assert ibm_start == ibm_result
def test_too_large(self):
with pytest.raises(OverflowError):
ieee2ibm(MAX_IBM_FLOAT * 10)
def test_too_small(self):
with pytest.raises(OverflowError):
ieee2ibm(MIN_IBM_FLOAT * 10)
def test_inf(self):
with pytest.raises(ValueError):
ieee2ibm(float('inf'))
def test_nan(self):
with pytest.raises(ValueError):
ieee2ibm(float('nan'))
def test_too_small_subnormal(self):
with pytest.raises(FloatingPointError):
ieee2ibm(1e-86)
def test_negative_half(self):
self.assertEqual(ieee2ibm(0.5), bytes((0b01000000, 0x80, 0x00, 0x00)))
def test_one(self):
ibm_start = b'\x41\x10\x00\x00'
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
assert ibm_start == ibm_result
def test_negative_118_625(self):
# Example taken from Wikipedia http://en.wikipedia.org/wiki/IBM_Floating_Point_Architecture
self.assertEqual(ieee2ibm(-118.625), bytes((0b11000010, 0b01110110, 0b10100000, 0b00000000)))
def test_subnormal(self):
ibm_start = bytes((0x00, 0x00, 0x00, 0x20))
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
assert ibm_start == ibm_result
def test_too_small_subnormal(self):
with self.assertRaises(FloatingPointError):
ieee2ibm(1e-86)
def test_nan(self):
with self.assertRaises(ValueError):
ieee2ibm(float('nan'))
def test_positive_half(self):
assert ieee2ibm(-0.5) == bytes((0b11000000, 0x80, 0x00, 0x00))
def test_inf(self):
with self.assertRaises(ValueError):
ieee2ibm(float('inf'))
def test_0_1(self):
# Note, this is different from the Wikipedia example, because the Wikipedia example does
# round to nearest, and our routine does round to zero
assert ieee2ibm(0.1) == bytes(
(0b01000000, 0b00011001, 0b10011001, 0b10011001))
def test_too_large(self):
with self.assertRaises(OverflowError):
ieee2ibm(MAX_IBM_FLOAT * 10)
def test_too_large(self):
with pytest.raises(OverflowError):
ieee2ibm(MAX_IBM_FLOAT * 10)
def test_too_small(self):
with self.assertRaises(OverflowError):
ieee2ibm(MIN_IBM_FLOAT * 10)
def test_one(self):
ibm_start = b'\x41\x10\x00\x00'
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
assert ibm_start == ibm_result
def test_zero(self):
ibm_start = b'\0\0\0\0'
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
self.assertEqual(ibm_start, ibm_result)
def test_subnormal(self):
ibm_start = bytes((0x00, 0x00, 0x00, 0x20))
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
self.assertEqual(ibm_start, ibm_result)
def test_positive_half(self):
ibm_start = bytes((0b11000000, 0x80, 0x00, 0x00))
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
self.assertEqual(ibm_start, ibm_result)
def test_positive_half(self):
self.assertEqual(ieee2ibm(-0.5), bytes((0b11000000, 0x80, 0x00, 0x00)))
def test_one(self):
ibm_start = b'\x41\x10\x00\x00'
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
self.assertEqual(ibm_start, ibm_result)
def test_one(self):
self.assertEqual(ieee2ibm(1.0), b'\x41\x10\x00\x00')
def test_subnormal(self):
ibm_start = bytes((0x00, 0x00, 0x00, 0x20))
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
self.assertEqual(ibm_start, ibm_result)
def test_0_1(self):
# Note, this is different from the Wikipedia example, because the Wikipedia example does
# round to nearest, and our routine does round to zero
self.assertEqual(ieee2ibm(0.1), bytes((0b01000000, 0b00011001, 0b10011001, 0b10011001)))
def test_zero(self):
self.assertEqual(ieee2ibm(0.0), b'\0\0\0\0')
def test_smallest_subnormal(self):
self.assertEqual(ieee2ibm(5.147557589468029e-85), bytes((0x00, 0x00, 0x00, 0x01)))
def test_positive_half(self):
self.assertEqual(ieee2ibm(-0.5), bytes((0b11000000, 0x80, 0x00, 0x00)))
def test_nan(self):
with self.assertRaises(ValueError):
ieee2ibm(float('nan'))
def test_negative_half(self):
self.assertEqual(ieee2ibm(0.5), bytes((0b01000000, 0x80, 0x00, 0x00)))
def test_zero(self):
assert ieee2ibm(0.0) == b'\0\0\0\0'
def test_one(self):
self.assertEqual(ieee2ibm(1.0), b'\x41\x10\x00\x00')
def test_negative_half(self):
assert ieee2ibm(0.5) == bytes((0b01000000, 0x80, 0x00, 0x00))
def test_smallest_subnormal(self):
assert ieee2ibm(5.147557589468029e-85) == bytes(
(0x00, 0x00, 0x00, 0x01))
def test_negative_118_625(self):
# Example taken from Wikipedia http://en.wikipedia.org/wiki/IBM_Floating_Point_Architecture
assert ieee2ibm(-118.625) == bytes(
(0b11000010, 0b01110110, 0b10100000, 0b00000000))
def test_nan(self):
with pytest.raises(ValueError):
ieee2ibm(float('nan'))
def test_subnormal(self):
assert ieee2ibm(1.6472184286297693e-83) == bytes(
(0x00, 0x00, 0x00, 0x20))
def test_subnormal(self):
assert ieee2ibm(1.6472184286297693e-83) == bytes((0x00, 0x00, 0x00, 0x20))
def test_too_small_subnormal(self):
with pytest.raises(FloatingPointError):
ieee2ibm(1e-86)
def test_too_large(self):
with self.assertRaises(OverflowError):
ieee2ibm(MAX_IBM_FLOAT * 10)
def test_inf(self):
with pytest.raises(ValueError):
ieee2ibm(float('inf'))
def test_too_small(self):
with self.assertRaises(OverflowError):
ieee2ibm(MIN_IBM_FLOAT * 10)
def test_too_small(self):
with pytest.raises(OverflowError):
ieee2ibm(MIN_IBM_FLOAT * 10)
def test_zero(self):
ibm_start = b'\0\0\0\0'
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
self.assertEqual(ibm_start, ibm_result)
def test_negative_half(self):
ibm_start = bytes((0b01000000, 0x80, 0x00, 0x00))
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
assert ibm_start == ibm_result
def test_negative_half(self):
ibm_start = bytes((0b01000000, 0x80, 0x00, 0x00))
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
self.assertEqual(ibm_start, ibm_result)
def test_subnormal(self):
ibm_start = bytes((0x00, 0x00, 0x00, 0x20))
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
assert ibm_start == ibm_result
def test_one(self):
ibm_start = b'\x41\x10\x00\x00'
f = ibm2ieee(ibm_start)
ibm_result = ieee2ibm(f)
self.assertEqual(ibm_start, ibm_result)
