Exemple #1
0
def test_is_similar():
    p1 = Point(2000, 2000)
    p2 = p1.scale(2, 2)

    r1 = Ray3D(Point3D(1, 1, 1), Point3D(1, 0, 0))
    r2 = Ray(Point(0, 0), Point(0, 1))

    s1 = Segment(Point(0, 0), p1)

    assert s1.is_similar(Segment(p1, p2))
    assert s1.is_similar(r2) is False
    assert r1.is_similar(Line3D(Point3D(1, 1, 1), Point3D(1, 0, 0))) is True
    assert r1.is_similar(Line3D(Point3D(0, 0, 0), Point3D(0, 1, 0))) is False
Exemple #2
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def test_is_similar():
    p1 = Point(2000, 2000)
    p2 = p1.scale(2, 2)

    r1 = Ray3D(Point3D(1, 1, 1), Point3D(1, 0, 0))
    r2 = Ray(Point(0, 0), Point(0, 1))

    s1 = Segment(Point(0, 0), p1)

    assert s1.is_similar(Segment(p1, p2))
    assert s1.is_similar(r2) is False
    assert r1.is_similar(Line3D(Point3D(1, 1, 1), Point3D(1, 0, 0))) is True
    assert r1.is_similar(Line3D(Point3D(0, 0, 0), Point3D(0, 1, 0))) is False
Exemple #3
0
def test_line():
    p1 = Point(0, 0)
    p2 = Point(1, 1)
    p3 = Point(x1, x1)
    p4 = Point(y1, y1)
    p5 = Point(x1, 1 + x1)
    p6 = Point(1, 0)
    p7 = Point(0, 1)
    p8 = Point(2, 0)
    p9 = Point(2, 1)

    l1 = Line(p1, p2)
    l2 = Line(p3, p4)
    l3 = Line(p3, p5)
    l4 = Line(p1, p6)
    l5 = Line(p1, p7)
    l6 = Line(p8, p9)
    l7 = Line(p2, p9)
    raises(ValueError, lambda: Line(Point(0, 0), Point(0, 0)))

    # Basic stuff
    assert Line((1, 1), slope=1) == Line((1, 1), (2, 2))
    assert Line((1, 1), slope=oo) == Line((1, 1), (1, 2))
    assert Line((1, 1), slope=-oo) == Line((1, 1), (1, 2))
    raises(ValueError, lambda: Line((1, 1), 1))
    assert Line(p1, p2) == Line(p2, p1)
    assert l1 == l2
    assert l1 != l3
    assert l1.slope == 1
    assert l1.length == oo
    assert l3.slope == oo
    assert l4.slope == 0
    assert l4.coefficients == (0, 1, 0)
    assert l4.equation(x=x, y=y) == y
    assert l5.slope == oo
    assert l5.coefficients == (1, 0, 0)
    assert l5.equation() == x
    assert l6.equation() == x - 2
    assert l7.equation() == y - 1
    assert p1 in l1  # is p1 on the line l1?
    assert p1 not in l3
    assert Line((-x, x), (-x + 1, x - 1)).coefficients == (1, 1, 0)

    assert simplify(l1.equation()) in (x - y, y - x)
    assert simplify(l3.equation()) in (x - x1, x1 - x)

    assert Line(p1, p2).scale(2, 1) == Line(p1, p9)

    assert l2.arbitrary_point() in l2
    for ind in xrange(0, 5):
        assert l3.random_point() in l3

    # Orthogonality
    p1_1 = Point(-x1, x1)
    l1_1 = Line(p1, p1_1)
    assert l1.perpendicular_line(p1) == l1_1
    assert Line.is_perpendicular(l1, l1_1)
    assert Line.is_perpendicular(l1, l2) == False
    p = l1.random_point()
    assert l1.perpendicular_segment(p) == p

    # Parallelity
    p2_1 = Point(-2 * x1, 0)
    l2_1 = Line(p3, p5)
    assert l2.parallel_line(p1_1) == Line(p2_1, p1_1)
    assert l2_1.parallel_line(p1) == Line(p1, Point(0, 2))
    assert Line.is_parallel(l1, l2)
    assert Line.is_parallel(l2, l3) == False
    assert Line.is_parallel(l2, l2.parallel_line(p1_1))
    assert Line.is_parallel(l2_1, l2_1.parallel_line(p1))

    # Intersection
    assert intersection(l1, p1) == [p1]
    assert intersection(l1, p5) == []
    assert intersection(l1, l2) in [[l1], [l2]]
    assert intersection(l1, l1.parallel_line(p5)) == []

    # Concurrency
    l3_1 = Line(Point(5, x1), Point(-Rational(3, 5), x1))
    assert Line.is_concurrent(l1) == False
    assert Line.is_concurrent(l1, l3)
    assert Line.is_concurrent(l1, l3, l3_1)
    assert Line.is_concurrent(l1, l1_1, l3) == False

    # Projection
    assert l2.projection(p4) == p4
    assert l1.projection(p1_1) == p1
    assert l3.projection(p2) == Point(x1, 1)
    raises(GeometryError, lambda: Line(Point(0, 0), Point(1, 0)).projection(Circle(Point(0, 0), 1)))

    # Finding angles
    l1_1 = Line(p1, Point(5, 0))
    assert feq(Line.angle_between(l1, l1_1).evalf(), pi.evalf() / 4)

    # Testing Rays and Segments (very similar to Lines)
    assert Ray((1, 1), angle=pi / 4) == Ray((1, 1), (2, 2))
    assert Ray((1, 1), angle=pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=-pi / 2) == Ray((1, 1), (1, 0))
    assert Ray((1, 1), angle=-3 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=5 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=5.0 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=pi) == Ray((1, 1), (0, 1))
    assert Ray((1, 1), angle=3.0 * pi) == Ray((1, 1), (0, 1))
    assert Ray((1, 1), angle=4.0 * pi) == Ray((1, 1), (2, 1))
    assert Ray((1, 1), angle=0) == Ray((1, 1), (2, 1))
    # XXX don't know why this fails without str
    assert str(Ray((1, 1), angle=4.2 * pi)) == str(Ray(Point(1, 1), Point(2, 1 + C.tan(0.2 * pi))))
    assert Ray((1, 1), angle=5) == Ray((1, 1), (2, 1 + C.tan(5)))
    raises(ValueError, lambda: Ray((1, 1), 1))

    r1 = Ray(p1, Point(-1, 5))
    r2 = Ray(p1, Point(-1, 1))
    r3 = Ray(p3, p5)
    r4 = Ray(p1, p2)
    r5 = Ray(p2, p1)
    r6 = Ray(Point(0, 1), Point(1, 2))
    r7 = Ray(Point(0.5, 0.5), Point(1, 1))
    assert l1.projection(r1) == Ray(p1, p2)
    assert l1.projection(r2) == p1
    assert r3 != r1
    t = Symbol("t", real=True)
    assert Ray((1, 1), angle=pi / 4).arbitrary_point() == Point(1 / (1 - t), 1 / (1 - t))

    s1 = Segment(p1, p2)
    s2 = Segment(p1, p1_1)
    assert s1.midpoint == Point(Rational(1, 2), Rational(1, 2))
    assert s2.length == sqrt(2 * (x1 ** 2))
    assert s1.perpendicular_bisector() == Line(Point(0, 1), Point(1, 0))
    assert Segment((1, 1), (2, 3)).arbitrary_point() == Point(1 + t, 1 + 2 * t)

    # intersections
    assert s1.intersection(Line(p6, p9)) == []
    s3 = Segment(Point(0.25, 0.25), Point(0.5, 0.5))
    assert s1.intersection(s3) == [s1]
    assert s3.intersection(s1) == [s3]
    assert r4.intersection(s3) == [s3]
    assert r4.intersection(Segment(Point(2, 3), Point(3, 4))) == []
    assert r4.intersection(Segment(Point(-1, -1), Point(0.5, 0.5))) == [Segment(p1, Point(0.5, 0.5))]
    s3 = Segment(Point(1, 1), Point(2, 2))
    assert s1.intersection(s3) == [Point(1, 1)]
    s3 = Segment(Point(0.5, 0.5), Point(1.5, 1.5))
    assert s1.intersection(s3) == [Segment(Point(0.5, 0.5), p2)]
    assert s1.intersection(Segment(Point(4, 4), Point(5, 5))) == []
    assert s1.intersection(Segment(Point(-1, -1), p1)) == [p1]
    assert s1.intersection(Segment(Point(-1, -1), Point(0.5, 0.5))) == [Segment(p1, Point(0.5, 0.5))]
    assert r4.intersection(r5) == [s1]
    assert r5.intersection(r6) == []
    assert r4.intersection(r7) == r7.intersection(r4) == [r7]

    # Segment contains
    a, b = symbols("a,b")
    s = Segment((0, a), (0, b))
    assert Point(0, (a + b) / 2) in s
    s = Segment((a, 0), (b, 0))
    assert Point((a + b) / 2, 0) in s

    raises(Undecidable, lambda: Point(2 * a, 0) in s)

    # Testing distance from a Segment to an object
    s1 = Segment(Point(0, 0), Point(1, 1))
    s2 = Segment(Point(half, half), Point(1, 0))
    pt1 = Point(0, 0)
    pt2 = Point(Rational(3) / 2, Rational(3) / 2)
    assert s1.distance(pt1) == 0
    assert s2.distance(pt1) == 2 ** (half) / 2
    assert s2.distance(pt2) == 2 ** (half)

    # Special cases of projection and intersection
    r1 = Ray(Point(1, 1), Point(2, 2))
    r2 = Ray(Point(2, 2), Point(0, 0))
    r3 = Ray(Point(1, 1), Point(-1, -1))
    r4 = Ray(Point(0, 4), Point(-1, -5))
    r5 = Ray(Point(2, 2), Point(3, 3))
    assert intersection(r1, r2) == [Segment(Point(1, 1), Point(2, 2))]
    assert intersection(r1, r3) == [Point(1, 1)]
    assert r1.projection(r3) == Point(1, 1)
    assert r1.projection(r4) == Segment(Point(1, 1), Point(2, 2))

    r5 = Ray(Point(0, 0), Point(0, 1))
    r6 = Ray(Point(0, 0), Point(0, 2))
    assert r5 in r6
    assert r6 in r5

    s1 = Segment(Point(0, 0), Point(2, 2))
    s2 = Segment(Point(-1, 5), Point(-5, -10))
    s3 = Segment(Point(0, 4), Point(-2, 2))
    assert intersection(r1, s1) == [Segment(Point(1, 1), Point(2, 2))]
    assert r1.projection(s2) == Segment(Point(1, 1), Point(2, 2))
    assert s3.projection(r1) == Segment(Point(0, 4), Point(-1, 3))

    l1 = Line(Point(0, 0), Point(3, 4))
    r1 = Ray(Point(0, 0), Point(3, 4))
    s1 = Segment(Point(0, 0), Point(3, 4))
    assert intersection(l1, l1) == [l1]
    assert intersection(l1, r1) == [r1]
    assert intersection(l1, s1) == [s1]
    assert intersection(r1, l1) == [r1]
    assert intersection(s1, l1) == [s1]

    entity1 = Segment(Point(-10, 10), Point(10, 10))
    entity2 = Segment(Point(-5, -5), Point(-5, 5))
    assert intersection(entity1, entity2) == []

    r1 = Ray(p1, Point(0, 1))
    r2 = Ray(Point(0, 1), p1)
    r3 = Ray(p1, p2)
    r4 = Ray(p2, p1)
    s1 = Segment(p1, Point(0, 1))
    assert Line(r1.source, r1.random_point()).slope == r1.slope
    assert Line(r2.source, r2.random_point()).slope == r2.slope
    assert Segment(Point(0, -1), s1.random_point()).slope == s1.slope
    p_r3 = r3.random_point()
    p_r4 = r4.random_point()
    assert p_r3.x >= p1.x and p_r3.y >= p1.y
    assert p_r4.x <= p2.x and p_r4.y <= p2.y
    p10 = Point(2000, 2000)
    s1 = Segment(p1, p10)
    p_s1 = s1.random_point()
    assert p1.x <= p_s1.x and p_s1.x <= p10.x and p1.y <= p_s1.y and p_s1.y <= p10.y
    s2 = Segment(p10, p1)

    assert hash(s1) == hash(s2)
    p11 = p10.scale(2, 2)
    assert s1.is_similar(Segment(p10, p11))
    assert s1.is_similar(r1) == False
    assert (r1 in s1) == False
    assert Segment(p1, p2) in s1
    assert s1.plot_interval() == [t, 0, 1]
    assert s1 in Line(p1, p10)
    assert Line(p1, p10) == Line(p10, p1)
    assert Line(p1, p10) != p1
    assert Line(p1, p10).plot_interval() == [t, -5, 5]
    assert Ray((0, 0), angle=pi / 4).plot_interval() == [t, 0, 5 * sqrt(2) / (1 + 5 * sqrt(2))]
Exemple #4
0
def test_line():
    p1 = Point(0, 0)
    p2 = Point(1, 1)
    p3 = Point(x1, x1)
    p4 = Point(y1, y1)
    p5 = Point(x1, 1 + x1)
    p6 = Point(1, 0)
    p7 = Point(0, 1)
    p8 = Point(2, 0)
    p9 = Point(2, 1)

    l1 = Line(p1, p2)
    l2 = Line(p3, p4)
    l3 = Line(p3, p5)
    l4 = Line(p1, p6)
    l5 = Line(p1, p7)
    l6 = Line(p8, p9)
    l7 = Line(p2, p9)
    raises(ValueError, 'Line(Point(0, 0), Point(0, 0))')

    # Basic stuff
    assert Line((1, 1), slope=1) == Line((1, 1), (2, 2))
    assert Line((1, 1), slope=oo) == Line((1, 1), (1, 2))
    assert Line((1, 1), slope=-oo) == Line((1, 1), (1, 2))
    raises(ValueError, 'Line((1, 1), 1)')
    assert Line(p1, p2) == Line(p2, p1)
    assert l1 == l2
    assert l1 != l3
    assert l1.slope == 1
    assert l1.length == oo
    assert l3.slope == oo
    assert l4.slope == 0
    assert l4.coefficients == (0, 1, 0)
    assert l4.equation(x=x, y=y) == y
    assert l5.slope == oo
    assert l5.coefficients == (1, 0, 0)
    assert l5.equation() == x
    assert l6.equation() == x - 2
    assert l7.equation() == y - 1
    assert p1 in l1  # is p1 on the line l1?
    assert p1 not in l3

    assert simplify(l1.equation()) in (x - y, y - x)
    assert simplify(l3.equation()) in (x - x1, x1 - x)

    assert Line(p1, p2).scale(2, 1) == Line(p1, p9)

    assert l2.arbitrary_point() in l2
    for ind in xrange(0, 5):
        assert l3.random_point() in l3

    # Orthogonality
    p1_1 = Point(-x1, x1)
    l1_1 = Line(p1, p1_1)
    assert l1.perpendicular_line(p1) == l1_1
    assert Line.is_perpendicular(l1, l1_1)
    assert Line.is_perpendicular(l1, l2) == False
    p = l1.random_point()
    assert l1.perpendicular_segment(p) == p

    # Parallelity
    p2_1 = Point(-2 * x1, 0)
    l2_1 = Line(p3, p5)
    assert l2.parallel_line(p1_1) == Line(p2_1, p1_1)
    assert l2_1.parallel_line(p1) == Line(p1, Point(0, 2))
    assert Line.is_parallel(l1, l2)
    assert Line.is_parallel(l2, l3) == False
    assert Line.is_parallel(l2, l2.parallel_line(p1_1))
    assert Line.is_parallel(l2_1, l2_1.parallel_line(p1))

    # Intersection
    assert intersection(l1, p1) == [p1]
    assert intersection(l1, p5) == []
    assert intersection(l1, l2) in [[l1], [l2]]
    assert intersection(l1, l1.parallel_line(p5)) == []

    # Concurrency
    l3_1 = Line(Point(5, x1), Point(-Rational(3, 5), x1))
    assert Line.is_concurrent(l1) == False
    assert Line.is_concurrent(l1, l3)
    assert Line.is_concurrent(l1, l3, l3_1)
    assert Line.is_concurrent(l1, l1_1, l3) == False

    # Projection
    assert l2.projection(p4) == p4
    assert l1.projection(p1_1) == p1
    assert l3.projection(p2) == Point(x1, 1)
    raises(
        GeometryError,
        'Line(Point(0, 0), Point(1, 0)).projection(Circle(Point(0, 0), 1))')

    # Finding angles
    l1_1 = Line(p1, Point(5, 0))
    assert feq(Line.angle_between(l1, l1_1).evalf(), pi.evalf() / 4)

    # Testing Rays and Segments (very similar to Lines)
    assert Ray((1, 1), angle=pi / 4) == Ray((1, 1), (2, 2))
    assert Ray((1, 1), angle=pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=-pi / 2) == Ray((1, 1), (1, 0))
    assert Ray((1, 1), angle=-3 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=5 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=5.0 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=pi) == Ray((1, 1), (0, 1))
    assert Ray((1, 1), angle=3.0 * pi) == Ray((1, 1), (0, 1))
    assert Ray((1, 1), angle=4.0 * pi) == Ray((1, 1), (2, 1))
    assert Ray((1, 1), angle=0) == Ray((1, 1), (2, 1))
    # XXX don't know why this fails without str
    assert str(Ray(
        (1, 1),
        angle=4.2 * pi)) == str(Ray(Point(1, 1), Point(2,
                                                       1 + C.tan(0.2 * pi))))
    assert Ray((1, 1), angle=5) == Ray((1, 1), (2, 1 + C.tan(5)))
    raises(ValueError, 'Ray((1, 1), 1)')

    r1 = Ray(p1, Point(-1, 5))
    r2 = Ray(p1, Point(-1, 1))
    r3 = Ray(p3, p5)
    r4 = Ray(p1, p2)
    r5 = Ray(p2, p1)
    r6 = Ray(Point(0, 1), Point(1, 2))
    r7 = Ray(Point(0.5, 0.5), Point(1, 1))
    assert l1.projection(r1) == Ray(p1, p2)
    assert l1.projection(r2) == p1
    assert r3 != r1
    t = Symbol('t', real=True)
    assert Ray(
        (1, 1),
        angle=pi / 4).arbitrary_point() == Point(1 / (1 - t), 1 / (1 - t))

    s1 = Segment(p1, p2)
    s2 = Segment(p1, p1_1)
    assert s1.midpoint == Point(Rational(1, 2), Rational(1, 2))
    assert s2.length == sqrt(2 * (x1**2))
    assert s1.perpendicular_bisector() == Line(Point(0, 1), Point(1, 0))
    assert Segment((1, 1), (2, 3)).arbitrary_point() == Point(1 + t, 1 + 2 * t)

    # intersections
    assert s1.intersection(Line(p6, p9)) == []
    s3 = Segment(Point(0.25, 0.25), Point(0.5, 0.5))
    assert s1.intersection(s3) == [s1]
    assert s3.intersection(s1) == [s3]
    assert r4.intersection(s3) == [s3]
    assert r4.intersection(Segment(Point(2, 3), Point(3, 4))) == []
    assert r4.intersection(Segment(Point(-1, -1), Point(
        0.5, 0.5))) == [Segment(p1, Point(0.5, 0.5))]
    s3 = Segment(Point(1, 1), Point(2, 2))
    assert s1.intersection(s3) == [Point(1, 1)]
    s3 = Segment(Point(0.5, 0.5), Point(1.5, 1.5))
    assert s1.intersection(s3) == [Segment(Point(0.5, 0.5), p2)]
    assert s1.intersection(Segment(Point(4, 4), Point(5, 5))) == []
    assert s1.intersection(Segment(Point(-1, -1), p1)) == [p1]
    assert s1.intersection(Segment(Point(-1, -1), Point(
        0.5, 0.5))) == [Segment(p1, Point(0.5, 0.5))]
    assert r4.intersection(r5) == [s1]
    assert r5.intersection(r6) == []
    assert r4.intersection(r7) == r7.intersection(r4) == [r7]

    # Segment contains
    a, b = symbols('a,b')
    s = Segment((0, a), (0, b))
    assert Point(0, (a + b) / 2) in s
    s = Segment((a, 0), (b, 0))
    assert Point((a + b) / 2, 0) in s

    raises(Undecidable, "Point(2*a, 0) in s")

    # Testing distance from a Segment to an object
    s1 = Segment(Point(0, 0), Point(1, 1))
    s2 = Segment(Point(half, half), Point(1, 0))
    pt1 = Point(0, 0)
    pt2 = Point(Rational(3) / 2, Rational(3) / 2)
    assert s1.distance(pt1) == 0
    assert s2.distance(pt1) == 2**(half) / 2
    assert s2.distance(pt2) == 2**(half)

    # Special cases of projection and intersection
    r1 = Ray(Point(1, 1), Point(2, 2))
    r2 = Ray(Point(2, 2), Point(0, 0))
    r3 = Ray(Point(1, 1), Point(-1, -1))
    r4 = Ray(Point(0, 4), Point(-1, -5))
    r5 = Ray(Point(2, 2), Point(3, 3))
    assert intersection(r1, r2) == [Segment(Point(1, 1), Point(2, 2))]
    assert intersection(r1, r3) == [Point(1, 1)]
    assert r1.projection(r3) == Point(1, 1)
    assert r1.projection(r4) == Segment(Point(1, 1), Point(2, 2))

    r5 = Ray(Point(0, 0), Point(0, 1))
    r6 = Ray(Point(0, 0), Point(0, 2))
    assert r5 in r6
    assert r6 in r5

    s1 = Segment(Point(0, 0), Point(2, 2))
    s2 = Segment(Point(-1, 5), Point(-5, -10))
    s3 = Segment(Point(0, 4), Point(-2, 2))
    assert intersection(r1, s1) == [Segment(Point(1, 1), Point(2, 2))]
    assert r1.projection(s2) == Segment(Point(1, 1), Point(2, 2))
    assert s3.projection(r1) == Segment(Point(0, 4), Point(-1, 3))

    l1 = Line(Point(0, 0), Point(3, 4))
    r1 = Ray(Point(0, 0), Point(3, 4))
    s1 = Segment(Point(0, 0), Point(3, 4))
    assert intersection(l1, l1) == [l1]
    assert intersection(l1, r1) == [r1]
    assert intersection(l1, s1) == [s1]
    assert intersection(r1, l1) == [r1]
    assert intersection(s1, l1) == [s1]

    entity1 = Segment(Point(-10, 10), Point(10, 10))
    entity2 = Segment(Point(-5, -5), Point(-5, 5))
    assert intersection(entity1, entity2) == []

    r1 = Ray(p1, Point(0, 1))
    r2 = Ray(Point(0, 1), p1)
    r3 = Ray(p1, p2)
    r4 = Ray(p2, p1)
    s1 = Segment(p1, Point(0, 1))
    assert Line(r1.source, r1.random_point()).slope == r1.slope
    assert Line(r2.source, r2.random_point()).slope == r2.slope
    assert Segment(Point(0, -1), s1.random_point()).slope == s1.slope
    p_r3 = r3.random_point()
    p_r4 = r4.random_point()
    assert p_r3.x >= p1.x and p_r3.y >= p1.y
    assert p_r4.x <= p2.x and p_r4.y <= p2.y
    p10 = Point(2000, 2000)
    s1 = Segment(p1, p10)
    p_s1 = s1.random_point()
    assert p1.x <= p_s1.x and p_s1.x <= p10.x and p1.y <= p_s1.y and p_s1.y <= p10.y
    s2 = Segment(p10, p1)

    assert hash(s1) == hash(s2)
    p11 = p10.scale(2, 2)
    assert s1.is_similar(Segment(p10, p11))
    assert s1.is_similar(r1) == False
    assert (r1 in s1) == False
    assert Segment(p1, p2) in s1
    assert s1.plot_interval() == [t, 0, 1]
    assert s1 in Line(p1, p10)
    assert Line(p1, p10) == Line(p10, p1)
    assert Line(p1, p10) != p1
    assert Line(p1, p10).plot_interval() == [t, -5, 5]
Exemple #5
0
def test_line_geom():
    x = Symbol('x', real=True)
    y = Symbol('y', real=True)
    x1 = Symbol('x1', real=True)
    y1 = Symbol('y1', real=True)
    half = Rational(1, 2)
    p1 = Point(0, 0)
    p2 = Point(1, 1)
    p3 = Point(x1, x1)
    p4 = Point(y1, y1)
    p5 = Point(x1, 1 + x1)
    p6 = Point(1, 0)
    p7 = Point(0, 1)
    p8 = Point(2, 0)
    p9 = Point(2, 1)

    l1 = Line(p1, p2)
    l2 = Line(p3, p4)
    l3 = Line(p3, p5)
    l4 = Line(p1, p6)
    l5 = Line(p1, p7)
    l6 = Line(p8, p9)
    l7 = Line(p2, p9)
    raises(ValueError, lambda: Line(Point(0, 0), Point(0, 0)))

    # Basic stuff
    assert Line((1, 1), slope=1) == Line((1, 1), (2, 2))
    assert Line((1, 1), slope=oo) == Line((1, 1), (1, 2))
    assert Line((1, 1), slope=-oo) == Line((1, 1), (1, 2))
    raises(TypeError, lambda: Line((1, 1), 1))
    assert Line(p1, p2) == Line(p1, p2)
    assert Line(p1, p2) != Line(p2, p1)
    assert l1 != l2
    assert l1 != l3
    assert l1.slope == 1
    assert l1.length == oo
    assert l3.slope == oo
    assert l4.slope == 0
    assert l4.coefficients == (0, 1, 0)
    assert l4.equation(x=x, y=y) == y
    assert l5.slope == oo
    assert l5.coefficients == (1, 0, 0)
    assert l5.equation() == x
    assert l6.equation() == x - 2
    assert l7.equation() == y - 1
    assert p1 in l1  # is p1 on the line l1?
    assert p1 not in l3
    assert Line((-x, x), (-x + 1, x - 1)).coefficients == (1, 1, 0)

    assert simplify(l1.equation()) in (x - y, y - x)
    assert simplify(l3.equation()) in (x - x1, x1 - x)

    assert Line(p1, p2).scale(2, 1) == Line(p1, p9)

    assert l2.arbitrary_point() in l2
    for ind in range(0, 5):
        assert l3.random_point() in l3

    # Orthogonality
    p1_1 = Point(-x1, x1)
    l1_1 = Line(p1, p1_1)
    assert l1.perpendicular_line(p1.args).equals(
        Line(Point(0, 0), Point(1, -1)))
    assert l1.perpendicular_line(p1).equals(Line(Point(0, 0), Point(1, -1)))
    assert Line.is_perpendicular(l1, l1_1)
    assert Line.is_perpendicular(l1, l2) is False
    p = l1.random_point()
    assert l1.perpendicular_segment(p) == p

    # Parallelity
    l2_1 = Line(p3, p5)
    assert l2.parallel_line(p1_1).equals(
        Line(Point(-x1, x1), Point(-y1, 2 * x1 - y1)))
    assert l2_1.parallel_line(p1.args).equals(Line(Point(0, 0), Point(0, -1)))
    assert l2_1.parallel_line(p1).equals(Line(Point(0, 0), Point(0, -1)))
    assert Line.is_parallel(l1, l2)
    assert Line.is_parallel(l2, l3) is False
    assert Line.is_parallel(l2, l2.parallel_line(p1_1))
    assert Line.is_parallel(l2_1, l2_1.parallel_line(p1))

    # Intersection
    assert intersection(l1, p1) == [p1]
    assert intersection(l1, p5) == []
    assert intersection(l1, l2) in [[l1], [l2]]
    assert intersection(l1, l1.parallel_line(p5)) == []

    # Concurrency
    l3_1 = Line(Point(5, x1), Point(-Rational(3, 5), x1))
    assert Line.are_concurrent(l1) is False
    assert Line.are_concurrent(l1, l3)
    assert Line.are_concurrent(l1, l1, l1, l3)
    assert Line.are_concurrent(l1, l3, l3_1)
    assert Line.are_concurrent(l1, l1_1, l3) is False

    # Projection
    assert l2.projection(p4) == p4
    assert l1.projection(p1_1) == p1
    assert l3.projection(p2) == Point(x1, 1)
    raises(
        GeometryError, lambda: Line(Point(0, 0), Point(1, 0)).projection(
            Circle(Point(0, 0), 1)))

    # Finding angles
    l1_1 = Line(p1, Point(5, 0))
    assert feq(Line.angle_between(l1, l1_1).evalf(), pi.evalf() / 4)
    a = Point(1, 2, 3, 4)
    b = a.orthogonal_direction
    o = a.origin
    assert Line(a, o).angle_between(Line(b, o)) == pi / 2

    # Testing Rays and Segments (very similar to Lines)
    assert Ray((1, 1), angle=pi / 4) == Ray((1, 1), (2, 2))
    assert Ray((1, 1), angle=pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=-pi / 2) == Ray((1, 1), (1, 0))
    assert Ray((1, 1), angle=-3 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=5 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=5.0 * pi / 2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=pi) == Ray((1, 1), (0, 1))
    assert Ray((1, 1), angle=3.0 * pi) == Ray((1, 1), (0, 1))
    assert Ray((1, 1), angle=4.0 * pi) == Ray((1, 1), (2, 1))
    assert Ray((1, 1), angle=0) == Ray((1, 1), (2, 1))
    assert Ray((1, 1), angle=4.05 * pi) == Ray(
        Point(1, 1),
        Point(
            2, -sqrt(5) * sqrt(2 * sqrt(5) + 10) / 4 -
            sqrt(2 * sqrt(5) + 10) / 4 + 2 + sqrt(5)))
    assert Ray((1, 1), angle=4.02 * pi) == Ray(Point(1, 1),
                                               Point(2, 1 + tan(4.02 * pi)))
    assert Ray((1, 1), angle=5) == Ray((1, 1), (2, 1 + tan(5)))
    raises(TypeError, lambda: Ray((1, 1), 1))

    # issue 7963
    r = Ray((0, 0), angle=x)
    assert r.subs(x, 3 * pi / 4) == Ray((0, 0), (-1, 1))
    assert r.subs(x, 5 * pi / 4) == Ray((0, 0), (-1, -1))
    assert r.subs(x, -pi / 4) == Ray((0, 0), (1, -1))
    assert r.subs(x, pi / 2) == Ray((0, 0), (0, 1))
    assert r.subs(x, -pi / 2) == Ray((0, 0), (0, -1))

    r1 = Ray(p1, Point(-1, 5))
    r2 = Ray(p1, Point(-1, 1))
    r3 = Ray(p3, p5)
    r4 = Ray(p1, p2)
    r5 = Ray(p2, p1)
    r6 = Ray(Point(0, 1), Point(1, 2))
    r7 = Ray(Point(0.5, 0.5), Point(1, 1))
    assert l1.projection(r1) == Ray(Point(0, 0), Point(2, 2))
    assert l1.projection(r2) == p1
    assert r3 != r1
    t = Symbol('t', real=True)
    assert Ray((1, 1), angle=pi/4).arbitrary_point() == \
        Point(t + 1, t + 1)
    r8 = Ray(Point(0, 0), Point(0, 4))
    r9 = Ray(Point(0, 1), Point(0, -1))
    assert r8.intersection(r9) == [Segment(Point(0, 0), Point(0, 1))]

    s1 = Segment(p1, p2)
    s2 = Segment(p1, p1_1)
    assert s1.midpoint == Point(Rational(1, 2), Rational(1, 2))
    assert s2.length == sqrt(2 * (x1**2))
    assert Segment((1, 1), (2, 3)).arbitrary_point() == Point(1 + t, 1 + 2 * t)
    aline = Line(Point(1 / 2, 1 / 2), Point(3 / 2, -1 / 2))
    assert s1.perpendicular_bisector().equals(aline)
    on_line = Segment(Point(1 / 2, 1 / 2), Point(3 / 2, -1 / 2)).midpoint
    assert s1.perpendicular_bisector(on_line) == Segment(s1.midpoint, on_line)
    assert s1.perpendicular_bisector(on_line + (1, 0)).equals(aline)
    # intersections
    assert s1.intersection(Line(p6, p9)) == []
    s3 = Segment(Point(0.25, 0.25), Point(0.5, 0.5))
    assert s1.intersection(s3) == [s3]
    assert s3.intersection(s1) == [s3]
    assert r4.intersection(s3) == [s3]
    assert r4.intersection(Segment(Point(2, 3), Point(3, 4))) == []
    assert r4.intersection(Segment(Point(-1, -1), Point(0.5, 0.5))) == \
        [Segment(p1, Point(0.5, 0.5))]
    s3 = Segment(Point(1, 1), Point(2, 2))
    assert s1.intersection(s3) == [Point(1, 1)]
    s3 = Segment(Point(0.5, 0.5), Point(1.5, 1.5))
    assert s1.intersection(s3) == [Segment(Point(0.5, 0.5), p2)]
    assert s1.intersection(Segment(Point(4, 4), Point(5, 5))) == []
    assert s1.intersection(Segment(Point(-1, -1), p1)) == [p1]
    assert s1.intersection(Segment(Point(-1, -1), Point(0.5, 0.5))) == \
        [Segment(p1, Point(0.5, 0.5))]
    assert r4.intersection(r5) == [s1]
    assert r5.intersection(r6) == []
    assert r4.intersection(r7) == r7.intersection(r4) == [r7]

    # Segment contains
    a, b = symbols('a,b', real=True)
    s = Segment((0, a), (0, b))
    assert Point(0, (a + b) / 2) in s
    s = Segment((a, 0), (b, 0))
    assert Point((a + b) / 2, 0) in s

    raises(Undecidable, lambda: Point(2 * a, 0) in s)

    # Testing distance from a Segment to an object
    s1 = Segment(Point(0, 0), Point(1, 1))
    s2 = Segment(Point(half, half), Point(1, 0))
    pt1 = Point(0, 0)
    pt2 = Point(Rational(3) / 2, Rational(3) / 2)
    assert s1.distance(pt1) == 0
    assert s1.distance((0, 0)) == 0
    assert s2.distance(pt1) == 2**(half) / 2
    assert s2.distance(pt2) == 2**(half)
    # Line to point
    p1, p2 = Point(0, 0), Point(1, 1)
    s = Line(p1, p2)
    assert s.distance(Point(-1, 1)) == sqrt(2)
    assert s.distance(Point(1, -1)) == sqrt(2)
    assert s.distance(Point(2, 2)) == 0
    assert s.distance((-1, 1)) == sqrt(2)
    assert Line((0, 0), (0, 1)).distance(p1) == 0
    assert Line((0, 0), (0, 1)).distance(p2) == 1
    assert Line((0, 0), (1, 0)).distance(p1) == 0
    assert Line((0, 0), (1, 0)).distance(p2) == 1
    m = symbols('m', real=True)
    l = Line((0, 5), slope=m)
    p = Point(2, 3)
    assert (l.distance(p) - 2 * abs(m + 1) / sqrt(m**2 + 1)).equals(0)
    # Ray to point
    r = Ray(p1, p2)
    assert r.distance(Point(-1, -1)) == sqrt(2)
    assert r.distance(Point(1, 1)) == 0
    assert r.distance(Point(-1, 1)) == sqrt(2)
    assert Ray((1, 1), (2, 2)).distance(Point(1.5, 3)) == 3 * sqrt(2) / 4
    assert r.distance((1, 1)) == 0

    #Line contains
    p1, p2 = Point(0, 1), Point(3, 4)
    l = Line(p1, p2)
    assert l.contains(p1) is True
    assert l.contains((0, 1)) is True
    assert l.contains((0, 0)) is False

    #Ray contains
    p1, p2 = Point(0, 0), Point(4, 4)
    r = Ray(p1, p2)
    assert r.contains(p1) is True
    assert r.contains((1, 1)) is True
    assert r.contains((1, 3)) is False
    s = Segment((1, 1), (2, 2))
    assert r.contains(s) is True
    s = Segment((1, 2), (2, 5))
    assert r.contains(s) is False
    r1 = Ray((2, 2), (3, 3))
    assert r.contains(r1) is True
    r1 = Ray((2, 2), (3, 5))
    assert r.contains(r1) is False

    # Special cases of projection and intersection
    r1 = Ray(Point(1, 1), Point(2, 2))
    r2 = Ray(Point(2, 2), Point(0, 0))
    r3 = Ray(Point(1, 1), Point(-1, -1))
    r4 = Ray(Point(0, 4), Point(-1, -5))
    r5 = Ray(Point(2, 2), Point(3, 3))
    assert intersection(r1, r2) == [Segment(Point(1, 1), Point(2, 2))]
    assert intersection(r1, r3) == [Point(1, 1)]
    assert r1.projection(r3) == Point(1, 1)
    assert r1.projection(r4) == Segment(Point(1, 1), Point(2, 2))

    r5 = Ray(Point(0, 0), Point(0, 1))
    r6 = Ray(Point(0, 0), Point(0, 2))
    assert r5 in r6
    assert r6 in r5

    s1 = Segment(Point(0, 0), Point(2, 2))
    s2 = Segment(Point(-1, 5), Point(-5, -10))
    s3 = Segment(Point(0, 4), Point(-2, 2))
    assert intersection(r1, s1) == [Segment(Point(1, 1), Point(2, 2))]
    assert r1.projection(s2) == Segment(Point(1, 1), Point(2, 2))
    assert s3.projection(r1) == Segment(Point(0, 4), Point(-1, 3))

    l1 = Line(Point(0, 0), Point(3, 4))
    r1 = Ray(Point(0, 0), Point(3, 4))
    s1 = Segment(Point(0, 0), Point(3, 4))
    assert intersection(l1, l1) == [l1]
    assert intersection(l1, r1) == [r1]
    assert intersection(l1, s1) == [s1]
    assert intersection(r1, l1) == [r1]
    assert intersection(s1, l1) == [s1]

    entity1 = Segment(Point(-10, 10), Point(10, 10))
    entity2 = Segment(Point(-5, -5), Point(-5, 5))
    assert intersection(entity1, entity2) == []

    r1 = Ray(p1, Point(0, 1))
    r2 = Ray(Point(0, 1), p1)
    r3 = Ray(p1, p2)
    r4 = Ray(p2, p1)
    s1 = Segment(p1, Point(0, 1))
    assert Line(r1.source, r1.random_point()).slope == r1.slope
    assert Line(r2.source, r2.random_point()).slope == r2.slope
    assert Segment(Point(0, -1), s1.random_point()).slope == s1.slope
    p_r3 = r3.random_point()
    p_r4 = r4.random_point()
    assert p_r3.x >= p1.x and p_r3.y >= p1.y
    assert p_r4.x <= p2.x and p_r4.y <= p2.y
    p10 = Point(2000, 2000)
    s1 = Segment(p1, p10)
    p_s1 = s1.random_point()
    assert p1.x <= p_s1.x and p_s1.x <= p10.x and \
        p1.y <= p_s1.y and p_s1.y <= p10.y
    s2 = Segment(p10, p1)
    assert hash(s1) == hash(s2)
    p11 = p10.scale(2, 2)
    assert s1.is_similar(Segment(p10, p11))
    assert s1.is_similar(r1) is False
    assert (r1 in s1) is False
    assert Segment(p1, p2) in s1
    assert s1.plot_interval() == [t, 0, 1]
    assert s1 in Line(p1, p10)
    assert Line(p1, p10) != Line(p10, p1)
    assert Line(p1, p10) != p1
    assert Line(p1, p10).plot_interval() == [t, -5, 5]
    assert Ray((0, 0), angle=pi/4).plot_interval() == \
        [t, 0, 10]
Exemple #6
0
def test_line_geom():
    x = Symbol('x', real=True)
    y = Symbol('y', real=True)
    x1 = Symbol('x1', real=True)
    y1 = Symbol('y1', real=True)
    half = Rational(1, 2)
    p1 = Point(0, 0)
    p2 = Point(1, 1)
    p3 = Point(x1, x1)
    p4 = Point(y1, y1)
    p5 = Point(x1, 1 + x1)
    p6 = Point(1, 0)
    p7 = Point(0, 1)
    p8 = Point(2, 0)
    p9 = Point(2, 1)

    l1 = Line(p1, p2)
    l2 = Line(p3, p4)
    l3 = Line(p3, p5)
    l4 = Line(p1, p6)
    l5 = Line(p1, p7)
    l6 = Line(p8, p9)
    l7 = Line(p2, p9)
    raises(ValueError, lambda: Line(Point(0, 0), Point(0, 0)))

    # Basic stuff
    assert Line((1, 1), slope=1) == Line((1, 1), (2, 2))
    assert Line((1, 1), slope=oo) == Line((1, 1), (1, 2))
    assert Line((1, 1), slope=-oo) == Line((1, 1), (1, 2))
    raises(TypeError, lambda: Line((1, 1), 1))
    assert Line(p1, p2) == Line(p1, p2)
    assert Line(p1, p2) != Line(p2, p1)
    assert l1 != l2
    assert l1 != l3
    assert l1.slope == 1
    assert l1.length == oo
    assert l3.slope == oo
    assert l4.slope == 0
    assert l4.coefficients == (0, 1, 0)
    assert l4.equation(x=x, y=y) == y
    assert l5.slope == oo
    assert l5.coefficients == (1, 0, 0)
    assert l5.equation() == x
    assert l6.equation() == x - 2
    assert l7.equation() == y - 1
    assert p1 in l1  # is p1 on the line l1?
    assert p1 not in l3
    assert Line((-x, x), (-x + 1, x - 1)).coefficients == (1, 1, 0)

    assert simplify(l1.equation()) in (x - y, y - x)
    assert simplify(l3.equation()) in (x - x1, x1 - x)

    assert Line(p1, p2).scale(2, 1) == Line(p1, p9)

    assert l2.arbitrary_point() in l2
    for ind in range(0, 5):
        assert l3.random_point() in l3

    # Orthogonality
    p1_1 = Point(-x1, x1)
    l1_1 = Line(p1, p1_1)
    assert l1.perpendicular_line(p1.args).equals( Line(Point(0, 0), Point(1, -1)) )
    assert l1.perpendicular_line(p1).equals( Line(Point(0, 0), Point(1, -1)) )
    assert Line.is_perpendicular(l1, l1_1)
    assert Line.is_perpendicular(l1, l2) is False
    p = l1.random_point()
    assert l1.perpendicular_segment(p) == p

    # Parallelity
    l2_1 = Line(p3, p5)
    assert l2.parallel_line(p1_1).equals( Line(Point(-x1, x1), Point(-y1, 2*x1 - y1)) )
    assert l2_1.parallel_line(p1.args).equals( Line(Point(0, 0), Point(0, -1)) )
    assert l2_1.parallel_line(p1).equals( Line(Point(0, 0), Point(0, -1)) )
    assert Line.is_parallel(l1, l2)
    assert Line.is_parallel(l2, l3) is False
    assert Line.is_parallel(l2, l2.parallel_line(p1_1))
    assert Line.is_parallel(l2_1, l2_1.parallel_line(p1))

    # Intersection
    assert intersection(l1, p1) == [p1]
    assert intersection(l1, p5) == []
    assert intersection(l1, l2) in [[l1], [l2]]
    assert intersection(l1, l1.parallel_line(p5)) == []

    # Concurrency
    l3_1 = Line(Point(5, x1), Point(-Rational(3, 5), x1))
    assert Line.are_concurrent(l1) is False
    assert Line.are_concurrent(l1, l3)
    assert Line.are_concurrent(l1, l1, l1, l3)
    assert Line.are_concurrent(l1, l3, l3_1)
    assert Line.are_concurrent(l1, l1_1, l3) is False

    # Projection
    assert l2.projection(p4) == p4
    assert l1.projection(p1_1) == p1
    assert l3.projection(p2) == Point(x1, 1)
    raises(GeometryError, lambda: Line(Point(0, 0), Point(1, 0))
           .projection(Circle(Point(0, 0), 1)))

    # Finding angles
    l1_1 = Line(p1, Point(5, 0))
    assert feq(Line.angle_between(l1, l1_1).evalf(), pi.evalf()/4)
    a = Point(1, 2, 3, 4)
    b = a.orthogonal_direction
    o = a.origin
    assert Line(a, o).angle_between(Line(b, o)) == pi/2

    # Testing Rays and Segments (very similar to Lines)
    assert Ray((1, 1), angle=pi/4) == Ray((1, 1), (2, 2))
    assert Ray((1, 1), angle=pi/2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=-pi/2) == Ray((1, 1), (1, 0))
    assert Ray((1, 1), angle=-3*pi/2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=5*pi/2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=5.0*pi/2) == Ray((1, 1), (1, 2))
    assert Ray((1, 1), angle=pi) == Ray((1, 1), (0, 1))
    assert Ray((1, 1), angle=3.0*pi) == Ray((1, 1), (0, 1))
    assert Ray((1, 1), angle=4.0*pi) == Ray((1, 1), (2, 1))
    assert Ray((1, 1), angle=0) == Ray((1, 1), (2, 1))
    assert Ray((1, 1), angle=4.05*pi) == Ray(Point(1, 1),
               Point(2, -sqrt(5)*sqrt(2*sqrt(5) + 10)/4 - sqrt(2*sqrt(5) + 10)/4 + 2 + sqrt(5)))
    assert Ray((1, 1), angle=4.02*pi) == Ray(Point(1, 1),
               Point(2, 1 + tan(4.02*pi)))
    assert Ray((1, 1), angle=5) == Ray((1, 1), (2, 1 + tan(5)))
    raises(TypeError, lambda: Ray((1, 1), 1))

    # issue 7963
    r = Ray((0, 0), angle=x)
    assert r.subs(x, 3*pi/4) == Ray((0, 0), (-1, 1))
    assert r.subs(x, 5*pi/4) == Ray((0, 0), (-1, -1))
    assert r.subs(x, -pi/4) == Ray((0, 0), (1, -1))
    assert r.subs(x, pi/2) == Ray((0, 0), (0, 1))
    assert r.subs(x, -pi/2) == Ray((0, 0), (0, -1))

    r1 = Ray(p1, Point(-1, 5))
    r2 = Ray(p1, Point(-1, 1))
    r3 = Ray(p3, p5)
    r4 = Ray(p1, p2)
    r5 = Ray(p2, p1)
    r6 = Ray(Point(0, 1), Point(1, 2))
    r7 = Ray(Point(0.5, 0.5), Point(1, 1))
    assert l1.projection(r1) == Ray(Point(0, 0), Point(2, 2))
    assert l1.projection(r2) == p1
    assert r3 != r1
    t = Symbol('t', real=True)
    assert Ray((1, 1), angle=pi/4).arbitrary_point() == \
        Point(t + 1, t + 1)
    r8 = Ray(Point(0, 0), Point(0, 4))
    r9 = Ray(Point(0, 1), Point(0, -1))
    assert r8.intersection(r9) == [Segment(Point(0, 0), Point(0, 1))]

    s1 = Segment(p1, p2)
    s2 = Segment(p1, p1_1)
    assert s1.midpoint == Point(Rational(1, 2), Rational(1, 2))
    assert s2.length == sqrt( 2*(x1**2) )
    assert Segment((1, 1), (2, 3)).arbitrary_point() == Point(1 + t, 1 + 2*t)
    aline = Line(Point(1/2, 1/2), Point(3/2, -1/2))
    assert s1.perpendicular_bisector().equals(aline)
    on_line = Segment(Point(1/2, 1/2), Point(3/2, -1/2)).midpoint
    assert s1.perpendicular_bisector(on_line) == Segment(s1.midpoint, on_line)
    assert s1.perpendicular_bisector(on_line + (1, 0)).equals(aline)
    # intersections
    assert s1.intersection(Line(p6, p9)) == []
    s3 = Segment(Point(0.25, 0.25), Point(0.5, 0.5))
    assert s1.intersection(s3) == [s3]
    assert s3.intersection(s1) == [s3]
    assert r4.intersection(s3) == [s3]
    assert r4.intersection(Segment(Point(2, 3), Point(3, 4))) == []
    assert r4.intersection(Segment(Point(-1, -1), Point(0.5, 0.5))) == \
        [Segment(p1, Point(0.5, 0.5))]
    s3 = Segment(Point(1, 1), Point(2, 2))
    assert s1.intersection(s3) == [Point(1, 1)]
    s3 = Segment(Point(0.5, 0.5), Point(1.5, 1.5))
    assert s1.intersection(s3) == [Segment(Point(0.5, 0.5), p2)]
    assert s1.intersection(Segment(Point(4, 4), Point(5, 5))) == []
    assert s1.intersection(Segment(Point(-1, -1), p1)) == [p1]
    assert s1.intersection(Segment(Point(-1, -1), Point(0.5, 0.5))) == \
        [Segment(p1, Point(0.5, 0.5))]
    assert r4.intersection(r5) == [s1]
    assert r5.intersection(r6) == []
    assert r4.intersection(r7) == r7.intersection(r4) == [r7]

    # Segment contains
    a, b = symbols('a,b', real=True)
    s = Segment((0, a), (0, b))
    assert Point(0, (a + b)/2) in s
    s = Segment((a, 0), (b, 0))
    assert Point((a + b)/2, 0) in s

    raises(Undecidable, lambda: Point(2*a, 0) in s)

    # Testing distance from a Segment to an object
    s1 = Segment(Point(0, 0), Point(1, 1))
    s2 = Segment(Point(half, half), Point(1, 0))
    pt1 = Point(0, 0)
    pt2 = Point(Rational(3)/2, Rational(3)/2)
    assert s1.distance(pt1) == 0
    assert s1.distance((0, 0)) == 0
    assert s2.distance(pt1) == 2**(half)/2
    assert s2.distance(pt2) == 2**(half)
    # Line to point
    p1, p2 = Point(0, 0), Point(1, 1)
    s = Line(p1, p2)
    assert s.distance(Point(-1, 1)) == sqrt(2)
    assert s.distance(Point(1, -1)) == sqrt(2)
    assert s.distance(Point(2, 2)) == 0
    assert s.distance((-1, 1)) == sqrt(2)
    assert Line((0, 0), (0, 1)).distance(p1) == 0
    assert Line((0, 0), (0, 1)).distance(p2) == 1
    assert Line((0, 0), (1, 0)).distance(p1) == 0
    assert Line((0, 0), (1, 0)).distance(p2) == 1
    m = symbols('m', real=True)
    l = Line((0, 5), slope=m)
    p = Point(2, 3)
    assert (l.distance(p) - 2*abs(m + 1)/sqrt(m**2 + 1)).equals(0)
    # Ray to point
    r = Ray(p1, p2)
    assert r.distance(Point(-1, -1)) == sqrt(2)
    assert r.distance(Point(1, 1)) == 0
    assert r.distance(Point(-1, 1)) == sqrt(2)
    assert Ray((1, 1), (2, 2)).distance(Point(1.5, 3)) == 3*sqrt(2)/4
    assert r.distance((1, 1)) == 0

    #Line contains
    p1, p2 = Point(0, 1), Point(3, 4)
    l = Line(p1, p2)
    assert l.contains(p1) is True
    assert l.contains((0, 1)) is True
    assert l.contains((0, 0)) is False

    #Ray contains
    p1, p2 = Point(0, 0), Point(4, 4)
    r = Ray(p1, p2)
    assert r.contains(p1) is True
    assert r.contains((1, 1)) is True
    assert r.contains((1, 3)) is False
    s = Segment((1, 1), (2, 2))
    assert r.contains(s) is True
    s = Segment((1, 2), (2, 5))
    assert r.contains(s) is False
    r1 = Ray((2, 2), (3, 3))
    assert r.contains(r1) is True
    r1 = Ray((2, 2), (3, 5))
    assert r.contains(r1) is False


    # Special cases of projection and intersection
    r1 = Ray(Point(1, 1), Point(2, 2))
    r2 = Ray(Point(2, 2), Point(0, 0))
    r3 = Ray(Point(1, 1), Point(-1, -1))
    r4 = Ray(Point(0, 4), Point(-1, -5))
    r5 = Ray(Point(2, 2), Point(3, 3))
    assert intersection(r1, r2) == [Segment(Point(1, 1), Point(2, 2))]
    assert intersection(r1, r3) == [Point(1, 1)]
    assert r1.projection(r3) == Point(1, 1)
    assert r1.projection(r4) == Segment(Point(1, 1), Point(2, 2))

    r5 = Ray(Point(0, 0), Point(0, 1))
    r6 = Ray(Point(0, 0), Point(0, 2))
    assert r5 in r6
    assert r6 in r5

    s1 = Segment(Point(0, 0), Point(2, 2))
    s2 = Segment(Point(-1, 5), Point(-5, -10))
    s3 = Segment(Point(0, 4), Point(-2, 2))
    assert intersection(r1, s1) == [Segment(Point(1, 1), Point(2, 2))]
    assert r1.projection(s2) == Segment(Point(1, 1), Point(2, 2))
    assert s3.projection(r1) == Segment(Point(0, 4), Point(-1, 3))

    l1 = Line(Point(0, 0), Point(3, 4))
    r1 = Ray(Point(0, 0), Point(3, 4))
    s1 = Segment(Point(0, 0), Point(3, 4))
    assert intersection(l1, l1) == [l1]
    assert intersection(l1, r1) == [r1]
    assert intersection(l1, s1) == [s1]
    assert intersection(r1, l1) == [r1]
    assert intersection(s1, l1) == [s1]

    entity1 = Segment(Point(-10, 10), Point(10, 10))
    entity2 = Segment(Point(-5, -5), Point(-5, 5))
    assert intersection(entity1, entity2) == []

    r1 = Ray(p1, Point(0, 1))
    r2 = Ray(Point(0, 1), p1)
    r3 = Ray(p1, p2)
    r4 = Ray(p2, p1)
    s1 = Segment(p1, Point(0, 1))
    assert Line(r1.source, r1.random_point()).slope == r1.slope
    assert Line(r2.source, r2.random_point()).slope == r2.slope
    assert Segment(Point(0, -1), s1.random_point()).slope == s1.slope
    p_r3 = r3.random_point()
    p_r4 = r4.random_point()
    assert p_r3.x >= p1.x and p_r3.y >= p1.y
    assert p_r4.x <= p2.x and p_r4.y <= p2.y
    p10 = Point(2000, 2000)
    s1 = Segment(p1, p10)
    p_s1 = s1.random_point()
    assert p1.x <= p_s1.x and p_s1.x <= p10.x and \
        p1.y <= p_s1.y and p_s1.y <= p10.y
    s2 = Segment(p10, p1)
    assert hash(s1) == hash(s2)
    p11 = p10.scale(2, 2)
    assert s1.is_similar(Segment(p10, p11))
    assert s1.is_similar(r1) is False
    assert (r1 in s1) is False
    assert Segment(p1, p2) in s1
    assert s1.plot_interval() == [t, 0, 1]
    assert s1 in Line(p1, p10)
    assert Line(p1, p10) != Line(p10, p1)
    assert Line(p1, p10) != p1
    assert Line(p1, p10).plot_interval() == [t, -5, 5]
    assert Ray((0, 0), angle=pi/4).plot_interval() == \
        [t, 0, 10]