def test_3_collinear_points_1_line():
points = [(0, 0), (1, 1), (2, 2)]
assert get_lines(points) == [(1, 0)]
assert len(get_lines(points)) == 1
pnt_set1 = [(0, 0), (-1, -1), (-2, -2)]
assert get_lines(pnt_set1) == [(1, 0)]
assert len(get_lines(pnt_set1)) == 1
pnt_set2 = [(0, 0), (-1, -1), (-2, -2)]
assert get_lines(pnt_set2) == [(1, 0)]
assert len(get_lines(pnt_set2)) == 1
pnt_set3 = [(4, -28), (9, -53), (0, -8)]
x0, y0 = pnt_set3[0]
x1, y1 = pnt_set3[2]
x2, y2 = pnt_set3[1]
slop = (y0 - y2) / (x0 - x2)
assert slop == (y2 - y1) / (x2 - x1)
intercept = y0 - slop * x0
assert intercept == y2 - slop * x2
assert intercept == y1 - slop * x1
assert len(get_lines(points)) == 1
assert get_lines(pnt_set3) == [(slop, intercept)]
pnt_set4 = [(9, -42), (-2, 2), (3, -18)]
x0, y0 = pnt_set4[0]
x1, y1 = pnt_set4[2]
x2, y2 = pnt_set4[1]
slop = (y0 - y2) / (x0 - x2)
assert slop == (y2 - y1) / (x2 - x1)
intercept = y0 - slop * x0
assert intercept == y2 - slop * x2
assert intercept == y1 - slop * x1
assert len(get_lines(points)) == 1
def test_raise_exception_if_xy_not_exactly_2_elements():
# Too many values to unpack
with pytest.raises(ValueError) as exception_info:
get_lines([(3, 2, 5), (4, -1, -1), (8, 1, 2), (-7, 0, 2)])
assert "too many values to unpack" in str(exception_info.value)
# Not enough values to unpack
with pytest.raises(ValueError) as exception_info:
get_lines([(3, ), (4, ), (8, ), (-7, )])
assert "not enough values to unpack" in str(exception_info.value)
def test_300_to_900_collinear_points_forming_100_lines():
collinear_points = random_collinear_points(
num_lines=100,
min_collinear_points_per_line=3,
max_collinear_points_per_line=
9, # each line can have `randomly` between 3 to 9 collinear points
)
assert len(get_lines(collinear_points)) == 100
def test_about_400_collinears_and_400_non_collinears_mixed():
mixed_points = random_collinear_points(
num_lines=100,
min_collinear_points_per_line=3,
max_collinear_points_per_line=5) + random_non_collinear_points(
num_non_collinears=400)
shuffle(mixed_points) # Randomly rearrange all points in-place
assert len(get_lines(mixed_points)) == 100
def test_10_x_axis_parallel_lines():
x_axis_parallel_lines = []
for _ in range(10):
y = randint(-100000, 100001)
x_axis_parallel_lines += [(randint(-10000, 10001), y)
for _ in range(10)]
shuffle(x_axis_parallel_lines)
assert len(get_lines(x_axis_parallel_lines)) == 10
def test_10_y_axis_parallel_lines():
y_axis_parallel_lines = []
for _ in range(10):
x = randint(-100000, 100001)
y_axis_parallel_lines += [(x, randint(-10000, 10001))
for _ in range(10)]
shuffle(y_axis_parallel_lines)
assert len(get_lines(y_axis_parallel_lines)) == 10
def test_less_than_3_points_input():
"""Correct Type but Insufficient Data"""
pnt_set0 = []
pnt_set1 = [(0, 0)]
pnt_set2 = [(0, 0), (1, 1)]
assert get_lines(pnt_set0) == []
assert get_lines(pnt_set0) == []
assert get_lines(pnt_set1) == []
assert get_lines(pnt_set2) == []
pnt_set3 = [(0, 0), (1, 1), (2, 2)] # collinear points
assert get_lines(pnt_set3) != []
assert len(get_lines(pnt_set3)) == 1
def test_300_collinear_points_forming_100_lines():
collinear_points = random_collinear_points(num_lines=100,
min_collinear_points_per_line=3,
max_collinear_points_per_line=3)
assert len(get_lines(collinear_points)) == 100
def test_200_non_collinear_points():
non_collinear_point = random_non_collinear_points(num_non_collinears=200)
# non_collinear_point = [(23, 6342), (42, 7777), (54, 1), (24111, 0), (6, 77)]
assert get_lines(non_collinear_point) == [
] # Expecting no line to be found
def test_raise_exception_if_input_type_not_list():
with pytest.raises(TypeError) as exception_info:
xy_input = ((-1, -1), (3, 3), (6, 6), (0, 0))
get_lines(xy_input)
assert "Expected input type is list." in str(exception_info.value)
def test_raise_exception_if_missing_input():
with pytest.raises(ValueError) as exception_info:
get_lines()
assert "Expected input argument is missing." in str(
exception_info.value)