def test_backward_divided_difference_gaps_step2(self):
"""
Backward divided difference with gaps in walker and step=2.
"""
orig = [(1, 5), (2, 4), (3, 4), (4, 4), (6, 4), (8, 3), (10, 6)]
expected = [(6, 0), (8, -0.5), (10, 1.5)]
walker = (('a', p, v) for p, v in orig)
assert_equal([(p, v) for _, p, v in backward_divided_difference(walker, step=2)], expected)
def test_backward_divided_difference_gaps(self):
"""
Backward divided difference with gaps in walker.
"""
orig = [(1, 5), (2, 4), (3, 4), (4, 4), (6, 4), (7, 3), (10, 6)]
expected = [(2, -1), (3, 0), (4, 0), (6, 0), (7, -1), (10, 1)]
walker = (('a', p, v) for p, v in orig)
assert_equal([(p, v) for _, p, v in backward_divided_difference(walker)], expected)
def test_backward_divided_difference(self):
"""
Simple backward divided difference.
"""
orig = [(1, 5), (2, 4), (3, 4), (4, 4), (5, 5), (6, 4), (7, 3), (8, 1), (9, 5), (10, 6)]
expected = [(2, -1), (3, 0), (4, 0), (5, 1), (6, -1), (7, -1), (8, -2), (9, 4), (10, 1)]
walker = (('a', p, v) for p, v in orig)
assert_equal([(p, v) for _, p, v in backward_divided_difference(walker)], expected)
def test_backward_divided_difference_gaps(self):
"""
Backward divided difference with gaps in walker.
"""
orig = [(1, 5), (2, 4), (3, 4), (4, 4), (6, 4), (7, 3), (10, 6)]
expected = [(2, -1), (3, 0), (4, 0), (6, 0), (7, -1), (10, 1)]
walker = (('a', p, v) for p, v in orig)
assert_equal([(p, v)
for _, p, v in backward_divided_difference(walker)],
expected)
def test_backward_divided_difference_gaps_step2(self):
"""
Backward divided difference with gaps in walker and step=2.
"""
orig = [(1, 5), (2, 4), (3, 4), (4, 4), (6, 4), (8, 3), (10, 6)]
expected = [(6, 0), (8, -0.5), (10, 1.5)]
walker = (('a', p, v) for p, v in orig)
assert_equal(
[(p, v)
for _, p, v in backward_divided_difference(walker, step=2)],
expected)
def test_backward_divided_difference(self):
"""
Simple backward divided difference.
"""
orig = [(1, 5), (2, 4), (3, 4), (4, 4), (5, 5), (6, 4), (7, 3), (8, 1),
(9, 5), (10, 6)]
expected = [(2, -1), (3, 0), (4, 0), (5, 1), (6, -1), (7, -1), (8, -2),
(9, 4), (10, 1)]
walker = (('a', p, v) for p, v in orig)
assert_equal([(p, v)
for _, p, v in backward_divided_difference(walker)],
expected)
