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602 lines
25 KiB
602 lines
25 KiB
5 months ago
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from sympy.core import expand
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from sympy.core.numbers import (Rational, oo, pi)
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from sympy.core.relational import Eq
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from sympy.core.singleton import S
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from sympy.core.symbol import (Symbol, symbols)
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from sympy.functions.elementary.complexes import Abs
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from sympy.functions.elementary.miscellaneous import sqrt
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from sympy.functions.elementary.trigonometric import sec
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from sympy.geometry.line import Segment2D
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from sympy.geometry.point import Point2D
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from sympy.geometry import (Circle, Ellipse, GeometryError, Line, Point,
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Polygon, Ray, RegularPolygon, Segment,
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Triangle, intersection)
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from sympy.testing.pytest import raises, slow
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from sympy.integrals.integrals import integrate
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from sympy.functions.special.elliptic_integrals import elliptic_e
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from sympy.functions.elementary.miscellaneous import Max
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def test_ellipse_equation_using_slope():
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from sympy.abc import x, y
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e1 = Ellipse(Point(1, 0), 3, 2)
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assert str(e1.equation(_slope=1)) == str((-x + y + 1)**2/8 + (x + y - 1)**2/18 - 1)
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e2 = Ellipse(Point(0, 0), 4, 1)
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assert str(e2.equation(_slope=1)) == str((-x + y)**2/2 + (x + y)**2/32 - 1)
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e3 = Ellipse(Point(1, 5), 6, 2)
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assert str(e3.equation(_slope=2)) == str((-2*x + y - 3)**2/20 + (x + 2*y - 11)**2/180 - 1)
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def test_object_from_equation():
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from sympy.abc import x, y, a, b, c, d, e
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assert Circle(x**2 + y**2 + 3*x + 4*y - 8) == Circle(Point2D(S(-3) / 2, -2), sqrt(57) / 2)
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assert Circle(x**2 + y**2 + 6*x + 8*y + 25) == Circle(Point2D(-3, -4), 0)
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assert Circle(a**2 + b**2 + 6*a + 8*b + 25, x='a', y='b') == Circle(Point2D(-3, -4), 0)
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assert Circle(x**2 + y**2 - 25) == Circle(Point2D(0, 0), 5)
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assert Circle(x**2 + y**2) == Circle(Point2D(0, 0), 0)
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assert Circle(a**2 + b**2, x='a', y='b') == Circle(Point2D(0, 0), 0)
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assert Circle(x**2 + y**2 + 6*x + 8) == Circle(Point2D(-3, 0), 1)
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assert Circle(x**2 + y**2 + 6*y + 8) == Circle(Point2D(0, -3), 1)
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assert Circle((x - 1)**2 + y**2 - 9) == Circle(Point2D(1, 0), 3)
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assert Circle(6*(x**2) + 6*(y**2) + 6*x + 8*y - 25) == Circle(Point2D(Rational(-1, 2), Rational(-2, 3)), 5*sqrt(7)/6)
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assert Circle(Eq(a**2 + b**2, 25), x='a', y=b) == Circle(Point2D(0, 0), 5)
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raises(GeometryError, lambda: Circle(x**2 + y**2 + 3*x + 4*y + 26))
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raises(GeometryError, lambda: Circle(x**2 + y**2 + 25))
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raises(GeometryError, lambda: Circle(a**2 + b**2 + 25, x='a', y='b'))
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raises(GeometryError, lambda: Circle(x**2 + 6*y + 8))
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raises(GeometryError, lambda: Circle(6*(x ** 2) + 4*(y**2) + 6*x + 8*y + 25))
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raises(ValueError, lambda: Circle(a**2 + b**2 + 3*a + 4*b - 8))
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# .equation() adds 'real=True' assumption; '==' would fail if assumptions differed
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x, y = symbols('x y', real=True)
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eq = a*x**2 + a*y**2 + c*x + d*y + e
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assert expand(Circle(eq).equation()*a) == eq
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@slow
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def test_ellipse_geom():
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x = Symbol('x', real=True)
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y = Symbol('y', real=True)
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t = Symbol('t', real=True)
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y1 = Symbol('y1', real=True)
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half = S.Half
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p1 = Point(0, 0)
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p2 = Point(1, 1)
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p4 = Point(0, 1)
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e1 = Ellipse(p1, 1, 1)
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e2 = Ellipse(p2, half, 1)
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e3 = Ellipse(p1, y1, y1)
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c1 = Circle(p1, 1)
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c2 = Circle(p2, 1)
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c3 = Circle(Point(sqrt(2), sqrt(2)), 1)
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l1 = Line(p1, p2)
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# Test creation with three points
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cen, rad = Point(3*half, 2), 5*half
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assert Circle(Point(0, 0), Point(3, 0), Point(0, 4)) == Circle(cen, rad)
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assert Circle(Point(0, 0), Point(1, 1), Point(2, 2)) == Segment2D(Point2D(0, 0), Point2D(2, 2))
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raises(ValueError, lambda: Ellipse(None, None, None, 1))
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raises(ValueError, lambda: Ellipse())
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raises(GeometryError, lambda: Circle(Point(0, 0)))
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raises(GeometryError, lambda: Circle(Symbol('x')*Symbol('y')))
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# Basic Stuff
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assert Ellipse(None, 1, 1).center == Point(0, 0)
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assert e1 == c1
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assert e1 != e2
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assert e1 != l1
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assert p4 in e1
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assert e1 in e1
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assert e2 in e2
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assert 1 not in e2
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assert p2 not in e2
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assert e1.area == pi
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assert e2.area == pi/2
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assert e3.area == pi*y1*abs(y1)
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assert c1.area == e1.area
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assert c1.circumference == e1.circumference
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assert e3.circumference == 2*pi*y1
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assert e1.plot_interval() == e2.plot_interval() == [t, -pi, pi]
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assert e1.plot_interval(x) == e2.plot_interval(x) == [x, -pi, pi]
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assert c1.minor == 1
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assert c1.major == 1
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assert c1.hradius == 1
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assert c1.vradius == 1
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assert Ellipse((1, 1), 0, 0) == Point(1, 1)
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assert Ellipse((1, 1), 1, 0) == Segment(Point(0, 1), Point(2, 1))
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assert Ellipse((1, 1), 0, 1) == Segment(Point(1, 0), Point(1, 2))
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# Private Functions
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assert hash(c1) == hash(Circle(Point(1, 0), Point(0, 1), Point(0, -1)))
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assert c1 in e1
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assert (Line(p1, p2) in e1) is False
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assert e1.__cmp__(e1) == 0
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assert e1.__cmp__(Point(0, 0)) > 0
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# Encloses
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assert e1.encloses(Segment(Point(-0.5, -0.5), Point(0.5, 0.5))) is True
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assert e1.encloses(Line(p1, p2)) is False
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assert e1.encloses(Ray(p1, p2)) is False
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assert e1.encloses(e1) is False
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assert e1.encloses(
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Polygon(Point(-0.5, -0.5), Point(-0.5, 0.5), Point(0.5, 0.5))) is True
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assert e1.encloses(RegularPolygon(p1, 0.5, 3)) is True
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assert e1.encloses(RegularPolygon(p1, 5, 3)) is False
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assert e1.encloses(RegularPolygon(p2, 5, 3)) is False
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assert e2.arbitrary_point() in e2
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raises(ValueError, lambda: Ellipse(Point(x, y), 1, 1).arbitrary_point(parameter='x'))
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# Foci
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f1, f2 = Point(sqrt(12), 0), Point(-sqrt(12), 0)
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ef = Ellipse(Point(0, 0), 4, 2)
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assert ef.foci in [(f1, f2), (f2, f1)]
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# Tangents
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v = sqrt(2) / 2
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p1_1 = Point(v, v)
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p1_2 = p2 + Point(half, 0)
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p1_3 = p2 + Point(0, 1)
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assert e1.tangent_lines(p4) == c1.tangent_lines(p4)
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assert e2.tangent_lines(p1_2) == [Line(Point(Rational(3, 2), 1), Point(Rational(3, 2), S.Half))]
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assert e2.tangent_lines(p1_3) == [Line(Point(1, 2), Point(Rational(5, 4), 2))]
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assert c1.tangent_lines(p1_1) != [Line(p1_1, Point(0, sqrt(2)))]
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assert c1.tangent_lines(p1) == []
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assert e2.is_tangent(Line(p1_2, p2 + Point(half, 1)))
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assert e2.is_tangent(Line(p1_3, p2 + Point(half, 1)))
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assert c1.is_tangent(Line(p1_1, Point(0, sqrt(2))))
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assert e1.is_tangent(Line(Point(0, 0), Point(1, 1))) is False
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assert c1.is_tangent(e1) is True
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assert c1.is_tangent(Ellipse(Point(2, 0), 1, 1)) is True
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assert c1.is_tangent(
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Polygon(Point(1, 1), Point(1, -1), Point(2, 0))) is True
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assert c1.is_tangent(
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Polygon(Point(1, 1), Point(1, 0), Point(2, 0))) is False
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assert Circle(Point(5, 5), 3).is_tangent(Circle(Point(0, 5), 1)) is False
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assert Ellipse(Point(5, 5), 2, 1).tangent_lines(Point(0, 0)) == \
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[Line(Point(0, 0), Point(Rational(77, 25), Rational(132, 25))),
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Line(Point(0, 0), Point(Rational(33, 5), Rational(22, 5)))]
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assert Ellipse(Point(5, 5), 2, 1).tangent_lines(Point(3, 4)) == \
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[Line(Point(3, 4), Point(4, 4)), Line(Point(3, 4), Point(3, 5))]
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assert Circle(Point(5, 5), 2).tangent_lines(Point(3, 3)) == \
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[Line(Point(3, 3), Point(4, 3)), Line(Point(3, 3), Point(3, 4))]
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assert Circle(Point(5, 5), 2).tangent_lines(Point(5 - 2*sqrt(2), 5)) == \
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[Line(Point(5 - 2*sqrt(2), 5), Point(5 - sqrt(2), 5 - sqrt(2))),
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Line(Point(5 - 2*sqrt(2), 5), Point(5 - sqrt(2), 5 + sqrt(2))), ]
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assert Circle(Point(5, 5), 5).tangent_lines(Point(4, 0)) == \
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[Line(Point(4, 0), Point(Rational(40, 13), Rational(5, 13))),
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Line(Point(4, 0), Point(5, 0))]
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assert Circle(Point(5, 5), 5).tangent_lines(Point(0, 6)) == \
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[Line(Point(0, 6), Point(0, 7)),
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Line(Point(0, 6), Point(Rational(5, 13), Rational(90, 13)))]
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# for numerical calculations, we shouldn't demand exact equality,
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# so only test up to the desired precision
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def lines_close(l1, l2, prec):
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""" tests whether l1 and 12 are within 10**(-prec)
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of each other """
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return abs(l1.p1 - l2.p1) < 10**(-prec) and abs(l1.p2 - l2.p2) < 10**(-prec)
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def line_list_close(ll1, ll2, prec):
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return all(lines_close(l1, l2, prec) for l1, l2 in zip(ll1, ll2))
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e = Ellipse(Point(0, 0), 2, 1)
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assert e.normal_lines(Point(0, 0)) == \
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[Line(Point(0, 0), Point(0, 1)), Line(Point(0, 0), Point(1, 0))]
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assert e.normal_lines(Point(1, 0)) == \
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[Line(Point(0, 0), Point(1, 0))]
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assert e.normal_lines((0, 1)) == \
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[Line(Point(0, 0), Point(0, 1))]
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assert line_list_close(e.normal_lines(Point(1, 1), 2), [
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Line(Point(Rational(-51, 26), Rational(-1, 5)), Point(Rational(-25, 26), Rational(17, 83))),
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Line(Point(Rational(28, 29), Rational(-7, 8)), Point(Rational(57, 29), Rational(-9, 2)))], 2)
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# test the failure of Poly.intervals and checks a point on the boundary
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p = Point(sqrt(3), S.Half)
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assert p in e
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assert line_list_close(e.normal_lines(p, 2), [
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Line(Point(Rational(-341, 171), Rational(-1, 13)), Point(Rational(-170, 171), Rational(5, 64))),
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Line(Point(Rational(26, 15), Rational(-1, 2)), Point(Rational(41, 15), Rational(-43, 26)))], 2)
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# be sure to use the slope that isn't undefined on boundary
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e = Ellipse((0, 0), 2, 2*sqrt(3)/3)
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assert line_list_close(e.normal_lines((1, 1), 2), [
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Line(Point(Rational(-64, 33), Rational(-20, 71)), Point(Rational(-31, 33), Rational(2, 13))),
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Line(Point(1, -1), Point(2, -4))], 2)
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# general ellipse fails except under certain conditions
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e = Ellipse((0, 0), x, 1)
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assert e.normal_lines((x + 1, 0)) == [Line(Point(0, 0), Point(1, 0))]
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raises(NotImplementedError, lambda: e.normal_lines((x + 1, 1)))
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# Properties
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major = 3
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minor = 1
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e4 = Ellipse(p2, minor, major)
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assert e4.focus_distance == sqrt(major**2 - minor**2)
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ecc = e4.focus_distance / major
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assert e4.eccentricity == ecc
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assert e4.periapsis == major*(1 - ecc)
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assert e4.apoapsis == major*(1 + ecc)
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assert e4.semilatus_rectum == major*(1 - ecc ** 2)
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# independent of orientation
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e4 = Ellipse(p2, major, minor)
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assert e4.focus_distance == sqrt(major**2 - minor**2)
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ecc = e4.focus_distance / major
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assert e4.eccentricity == ecc
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assert e4.periapsis == major*(1 - ecc)
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assert e4.apoapsis == major*(1 + ecc)
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# Intersection
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l1 = Line(Point(1, -5), Point(1, 5))
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l2 = Line(Point(-5, -1), Point(5, -1))
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l3 = Line(Point(-1, -1), Point(1, 1))
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l4 = Line(Point(-10, 0), Point(0, 10))
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pts_c1_l3 = [Point(sqrt(2)/2, sqrt(2)/2), Point(-sqrt(2)/2, -sqrt(2)/2)]
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assert intersection(e2, l4) == []
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assert intersection(c1, Point(1, 0)) == [Point(1, 0)]
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assert intersection(c1, l1) == [Point(1, 0)]
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assert intersection(c1, l2) == [Point(0, -1)]
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assert intersection(c1, l3) in [pts_c1_l3, [pts_c1_l3[1], pts_c1_l3[0]]]
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assert intersection(c1, c2) == [Point(0, 1), Point(1, 0)]
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assert intersection(c1, c3) == [Point(sqrt(2)/2, sqrt(2)/2)]
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assert e1.intersection(l1) == [Point(1, 0)]
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assert e2.intersection(l4) == []
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assert e1.intersection(Circle(Point(0, 2), 1)) == [Point(0, 1)]
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assert e1.intersection(Circle(Point(5, 0), 1)) == []
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assert e1.intersection(Ellipse(Point(2, 0), 1, 1)) == [Point(1, 0)]
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assert e1.intersection(Ellipse(Point(5, 0), 1, 1)) == []
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assert e1.intersection(Point(2, 0)) == []
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assert e1.intersection(e1) == e1
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assert intersection(Ellipse(Point(0, 0), 2, 1), Ellipse(Point(3, 0), 1, 2)) == [Point(2, 0)]
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assert intersection(Circle(Point(0, 0), 2), Circle(Point(3, 0), 1)) == [Point(2, 0)]
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assert intersection(Circle(Point(0, 0), 2), Circle(Point(7, 0), 1)) == []
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assert intersection(Ellipse(Point(0, 0), 5, 17), Ellipse(Point(4, 0), 1, 0.2)) == [Point(5, 0)]
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assert intersection(Ellipse(Point(0, 0), 5, 17), Ellipse(Point(4, 0), 0.999, 0.2)) == []
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assert Circle((0, 0), S.Half).intersection(
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Triangle((-1, 0), (1, 0), (0, 1))) == [
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Point(Rational(-1, 2), 0), Point(S.Half, 0)]
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raises(TypeError, lambda: intersection(e2, Line((0, 0, 0), (0, 0, 1))))
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raises(TypeError, lambda: intersection(e2, Rational(12)))
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raises(TypeError, lambda: Ellipse.intersection(e2, 1))
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# some special case intersections
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csmall = Circle(p1, 3)
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cbig = Circle(p1, 5)
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cout = Circle(Point(5, 5), 1)
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# one circle inside of another
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assert csmall.intersection(cbig) == []
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# separate circles
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assert csmall.intersection(cout) == []
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# coincident circles
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assert csmall.intersection(csmall) == csmall
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v = sqrt(2)
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t1 = Triangle(Point(0, v), Point(0, -v), Point(v, 0))
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points = intersection(t1, c1)
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assert len(points) == 4
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assert Point(0, 1) in points
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assert Point(0, -1) in points
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assert Point(v/2, v/2) in points
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assert Point(v/2, -v/2) in points
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circ = Circle(Point(0, 0), 5)
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elip = Ellipse(Point(0, 0), 5, 20)
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assert intersection(circ, elip) in \
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[[Point(5, 0), Point(-5, 0)], [Point(-5, 0), Point(5, 0)]]
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assert elip.tangent_lines(Point(0, 0)) == []
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elip = Ellipse(Point(0, 0), 3, 2)
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assert elip.tangent_lines(Point(3, 0)) == \
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[Line(Point(3, 0), Point(3, -12))]
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e1 = Ellipse(Point(0, 0), 5, 10)
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e2 = Ellipse(Point(2, 1), 4, 8)
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a = Rational(53, 17)
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c = 2*sqrt(3991)/17
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ans = [Point(a - c/8, a/2 + c), Point(a + c/8, a/2 - c)]
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assert e1.intersection(e2) == ans
|
||
|
e2 = Ellipse(Point(x, y), 4, 8)
|
||
|
c = sqrt(3991)
|
||
|
ans = [Point(-c/68 + a, c*Rational(2, 17) + a/2), Point(c/68 + a, c*Rational(-2, 17) + a/2)]
|
||
|
assert [p.subs({x: 2, y:1}) for p in e1.intersection(e2)] == ans
|
||
|
|
||
|
# Combinations of above
|
||
|
assert e3.is_tangent(e3.tangent_lines(p1 + Point(y1, 0))[0])
|
||
|
|
||
|
e = Ellipse((1, 2), 3, 2)
|
||
|
assert e.tangent_lines(Point(10, 0)) == \
|
||
|
[Line(Point(10, 0), Point(1, 0)),
|
||
|
Line(Point(10, 0), Point(Rational(14, 5), Rational(18, 5)))]
|
||
|
|
||
|
# encloses_point
|
||
|
e = Ellipse((0, 0), 1, 2)
|
||
|
assert e.encloses_point(e.center)
|
||
|
assert e.encloses_point(e.center + Point(0, e.vradius - Rational(1, 10)))
|
||
|
assert e.encloses_point(e.center + Point(e.hradius - Rational(1, 10), 0))
|
||
|
assert e.encloses_point(e.center + Point(e.hradius, 0)) is False
|
||
|
assert e.encloses_point(
|
||
|
e.center + Point(e.hradius + Rational(1, 10), 0)) is False
|
||
|
e = Ellipse((0, 0), 2, 1)
|
||
|
assert e.encloses_point(e.center)
|
||
|
assert e.encloses_point(e.center + Point(0, e.vradius - Rational(1, 10)))
|
||
|
assert e.encloses_point(e.center + Point(e.hradius - Rational(1, 10), 0))
|
||
|
assert e.encloses_point(e.center + Point(e.hradius, 0)) is False
|
||
|
assert e.encloses_point(
|
||
|
e.center + Point(e.hradius + Rational(1, 10), 0)) is False
|
||
|
assert c1.encloses_point(Point(1, 0)) is False
|
||
|
assert c1.encloses_point(Point(0.3, 0.4)) is True
|
||
|
|
||
|
assert e.scale(2, 3) == Ellipse((0, 0), 4, 3)
|
||
|
assert e.scale(3, 6) == Ellipse((0, 0), 6, 6)
|
||
|
assert e.rotate(pi) == e
|
||
|
assert e.rotate(pi, (1, 2)) == Ellipse(Point(2, 4), 2, 1)
|
||
|
raises(NotImplementedError, lambda: e.rotate(pi/3))
|
||
|
|
||
|
# Circle rotation tests (Issue #11743)
|
||
|
# Link - https://github.com/sympy/sympy/issues/11743
|
||
|
cir = Circle(Point(1, 0), 1)
|
||
|
assert cir.rotate(pi/2) == Circle(Point(0, 1), 1)
|
||
|
assert cir.rotate(pi/3) == Circle(Point(S.Half, sqrt(3)/2), 1)
|
||
|
assert cir.rotate(pi/3, Point(1, 0)) == Circle(Point(1, 0), 1)
|
||
|
assert cir.rotate(pi/3, Point(0, 1)) == Circle(Point(S.Half + sqrt(3)/2, S.Half + sqrt(3)/2), 1)
|
||
|
|
||
|
|
||
|
def test_construction():
|
||
|
e1 = Ellipse(hradius=2, vradius=1, eccentricity=None)
|
||
|
assert e1.eccentricity == sqrt(3)/2
|
||
|
|
||
|
e2 = Ellipse(hradius=2, vradius=None, eccentricity=sqrt(3)/2)
|
||
|
assert e2.vradius == 1
|
||
|
|
||
|
e3 = Ellipse(hradius=None, vradius=1, eccentricity=sqrt(3)/2)
|
||
|
assert e3.hradius == 2
|
||
|
|
||
|
# filter(None, iterator) filters out anything falsey, including 0
|
||
|
# eccentricity would be filtered out in this case and the constructor would throw an error
|
||
|
e4 = Ellipse(Point(0, 0), hradius=1, eccentricity=0)
|
||
|
assert e4.vradius == 1
|
||
|
|
||
|
#tests for eccentricity > 1
|
||
|
raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity = S(3)/2))
|
||
|
raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity=sec(5)))
|
||
|
raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity=S.Pi-S(2)))
|
||
|
|
||
|
#tests for eccentricity = 1
|
||
|
#if vradius is not defined
|
||
|
assert Ellipse(None, 1, None, 1).length == 2
|
||
|
#if hradius is not defined
|
||
|
raises(GeometryError, lambda: Ellipse(None, None, 1, eccentricity = 1))
|
||
|
|
||
|
#tests for eccentricity < 0
|
||
|
raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity = -3))
|
||
|
raises(GeometryError, lambda: Ellipse(Point(3, 1), hradius=3, eccentricity = -0.5))
|
||
|
|
||
|
def test_ellipse_random_point():
|
||
|
y1 = Symbol('y1', real=True)
|
||
|
e3 = Ellipse(Point(0, 0), y1, y1)
|
||
|
rx, ry = Symbol('rx'), Symbol('ry')
|
||
|
for ind in range(0, 5):
|
||
|
r = e3.random_point()
|
||
|
# substitution should give zero*y1**2
|
||
|
assert e3.equation(rx, ry).subs(zip((rx, ry), r.args)).equals(0)
|
||
|
# test for the case with seed
|
||
|
r = e3.random_point(seed=1)
|
||
|
assert e3.equation(rx, ry).subs(zip((rx, ry), r.args)).equals(0)
|
||
|
|
||
|
|
||
|
def test_repr():
|
||
|
assert repr(Circle((0, 1), 2)) == 'Circle(Point2D(0, 1), 2)'
|
||
|
|
||
|
|
||
|
def test_transform():
|
||
|
c = Circle((1, 1), 2)
|
||
|
assert c.scale(-1) == Circle((-1, 1), 2)
|
||
|
assert c.scale(y=-1) == Circle((1, -1), 2)
|
||
|
assert c.scale(2) == Ellipse((2, 1), 4, 2)
|
||
|
|
||
|
assert Ellipse((0, 0), 2, 3).scale(2, 3, (4, 5)) == \
|
||
|
Ellipse(Point(-4, -10), 4, 9)
|
||
|
assert Circle((0, 0), 2).scale(2, 3, (4, 5)) == \
|
||
|
Ellipse(Point(-4, -10), 4, 6)
|
||
|
assert Ellipse((0, 0), 2, 3).scale(3, 3, (4, 5)) == \
|
||
|
Ellipse(Point(-8, -10), 6, 9)
|
||
|
assert Circle((0, 0), 2).scale(3, 3, (4, 5)) == \
|
||
|
Circle(Point(-8, -10), 6)
|
||
|
assert Circle(Point(-8, -10), 6).scale(Rational(1, 3), Rational(1, 3), (4, 5)) == \
|
||
|
Circle((0, 0), 2)
|
||
|
assert Circle((0, 0), 2).translate(4, 5) == \
|
||
|
Circle((4, 5), 2)
|
||
|
assert Circle((0, 0), 2).scale(3, 3) == \
|
||
|
Circle((0, 0), 6)
|
||
|
|
||
|
|
||
|
def test_bounds():
|
||
|
e1 = Ellipse(Point(0, 0), 3, 5)
|
||
|
e2 = Ellipse(Point(2, -2), 7, 7)
|
||
|
c1 = Circle(Point(2, -2), 7)
|
||
|
c2 = Circle(Point(-2, 0), Point(0, 2), Point(2, 0))
|
||
|
assert e1.bounds == (-3, -5, 3, 5)
|
||
|
assert e2.bounds == (-5, -9, 9, 5)
|
||
|
assert c1.bounds == (-5, -9, 9, 5)
|
||
|
assert c2.bounds == (-2, -2, 2, 2)
|
||
|
|
||
|
|
||
|
def test_reflect():
|
||
|
b = Symbol('b')
|
||
|
m = Symbol('m')
|
||
|
l = Line((0, b), slope=m)
|
||
|
t1 = Triangle((0, 0), (1, 0), (2, 3))
|
||
|
assert t1.area == -t1.reflect(l).area
|
||
|
e = Ellipse((1, 0), 1, 2)
|
||
|
assert e.area == -e.reflect(Line((1, 0), slope=0)).area
|
||
|
assert e.area == -e.reflect(Line((1, 0), slope=oo)).area
|
||
|
raises(NotImplementedError, lambda: e.reflect(Line((1, 0), slope=m)))
|
||
|
assert Circle((0, 1), 1).reflect(Line((0, 0), (1, 1))) == Circle(Point2D(1, 0), -1)
|
||
|
|
||
|
|
||
|
def test_is_tangent():
|
||
|
e1 = Ellipse(Point(0, 0), 3, 5)
|
||
|
c1 = Circle(Point(2, -2), 7)
|
||
|
assert e1.is_tangent(Point(0, 0)) is False
|
||
|
assert e1.is_tangent(Point(3, 0)) is False
|
||
|
assert e1.is_tangent(e1) is True
|
||
|
assert e1.is_tangent(Ellipse((0, 0), 1, 2)) is False
|
||
|
assert e1.is_tangent(Ellipse((0, 0), 3, 2)) is True
|
||
|
assert c1.is_tangent(Ellipse((2, -2), 7, 1)) is True
|
||
|
assert c1.is_tangent(Circle((11, -2), 2)) is True
|
||
|
assert c1.is_tangent(Circle((7, -2), 2)) is True
|
||
|
assert c1.is_tangent(Ray((-5, -2), (-15, -20))) is False
|
||
|
assert c1.is_tangent(Ray((-3, -2), (-15, -20))) is False
|
||
|
assert c1.is_tangent(Ray((-3, -22), (15, 20))) is False
|
||
|
assert c1.is_tangent(Ray((9, 20), (9, -20))) is True
|
||
|
assert e1.is_tangent(Segment((2, 2), (-7, 7))) is False
|
||
|
assert e1.is_tangent(Segment((0, 0), (1, 2))) is False
|
||
|
assert c1.is_tangent(Segment((0, 0), (-5, -2))) is False
|
||
|
assert e1.is_tangent(Segment((3, 0), (12, 12))) is False
|
||
|
assert e1.is_tangent(Segment((12, 12), (3, 0))) is False
|
||
|
assert e1.is_tangent(Segment((-3, 0), (3, 0))) is False
|
||
|
assert e1.is_tangent(Segment((-3, 5), (3, 5))) is True
|
||
|
assert e1.is_tangent(Line((10, 0), (10, 10))) is False
|
||
|
assert e1.is_tangent(Line((0, 0), (1, 1))) is False
|
||
|
assert e1.is_tangent(Line((-3, 0), (-2.99, -0.001))) is False
|
||
|
assert e1.is_tangent(Line((-3, 0), (-3, 1))) is True
|
||
|
assert e1.is_tangent(Polygon((0, 0), (5, 5), (5, -5))) is False
|
||
|
assert e1.is_tangent(Polygon((-100, -50), (-40, -334), (-70, -52))) is False
|
||
|
assert e1.is_tangent(Polygon((-3, 0), (3, 0), (0, 1))) is False
|
||
|
assert e1.is_tangent(Polygon((-3, 0), (3, 0), (0, 5))) is False
|
||
|
assert e1.is_tangent(Polygon((-3, 0), (0, -5), (3, 0), (0, 5))) is False
|
||
|
assert e1.is_tangent(Polygon((-3, -5), (-3, 5), (3, 5), (3, -5))) is True
|
||
|
assert c1.is_tangent(Polygon((-3, -5), (-3, 5), (3, 5), (3, -5))) is False
|
||
|
assert e1.is_tangent(Polygon((0, 0), (3, 0), (7, 7), (0, 5))) is False
|
||
|
assert e1.is_tangent(Polygon((3, 12), (3, -12), (6, 5))) is True
|
||
|
assert e1.is_tangent(Polygon((3, 12), (3, -12), (0, -5), (0, 5))) is False
|
||
|
assert e1.is_tangent(Polygon((3, 0), (5, 7), (6, -5))) is False
|
||
|
raises(TypeError, lambda: e1.is_tangent(Point(0, 0, 0)))
|
||
|
raises(TypeError, lambda: e1.is_tangent(Rational(5)))
|
||
|
|
||
|
|
||
|
def test_parameter_value():
|
||
|
t = Symbol('t')
|
||
|
e = Ellipse(Point(0, 0), 3, 5)
|
||
|
assert e.parameter_value((3, 0), t) == {t: 0}
|
||
|
raises(ValueError, lambda: e.parameter_value((4, 0), t))
|
||
|
|
||
|
|
||
|
@slow
|
||
|
def test_second_moment_of_area():
|
||
|
x, y = symbols('x, y')
|
||
|
e = Ellipse(Point(0, 0), 5, 4)
|
||
|
I_yy = 2*4*integrate(sqrt(25 - x**2)*x**2, (x, -5, 5))/5
|
||
|
I_xx = 2*5*integrate(sqrt(16 - y**2)*y**2, (y, -4, 4))/4
|
||
|
Y = 3*sqrt(1 - x**2/5**2)
|
||
|
I_xy = integrate(integrate(y, (y, -Y, Y))*x, (x, -5, 5))
|
||
|
assert I_yy == e.second_moment_of_area()[1]
|
||
|
assert I_xx == e.second_moment_of_area()[0]
|
||
|
assert I_xy == e.second_moment_of_area()[2]
|
||
|
#checking for other point
|
||
|
t1 = e.second_moment_of_area(Point(6,5))
|
||
|
t2 = (580*pi, 845*pi, 600*pi)
|
||
|
assert t1==t2
|
||
|
|
||
|
|
||
|
def test_section_modulus_and_polar_second_moment_of_area():
|
||
|
d = Symbol('d', positive=True)
|
||
|
c = Circle((3, 7), 8)
|
||
|
assert c.polar_second_moment_of_area() == 2048*pi
|
||
|
assert c.section_modulus() == (128*pi, 128*pi)
|
||
|
c = Circle((2, 9), d/2)
|
||
|
assert c.polar_second_moment_of_area() == pi*d**3*Abs(d)/64 + pi*d*Abs(d)**3/64
|
||
|
assert c.section_modulus() == (pi*d**3/S(32), pi*d**3/S(32))
|
||
|
|
||
|
a, b = symbols('a, b', positive=True)
|
||
|
e = Ellipse((4, 6), a, b)
|
||
|
assert e.section_modulus() == (pi*a*b**2/S(4), pi*a**2*b/S(4))
|
||
|
assert e.polar_second_moment_of_area() == pi*a**3*b/S(4) + pi*a*b**3/S(4)
|
||
|
e = e.rotate(pi/2) # no change in polar and section modulus
|
||
|
assert e.section_modulus() == (pi*a**2*b/S(4), pi*a*b**2/S(4))
|
||
|
assert e.polar_second_moment_of_area() == pi*a**3*b/S(4) + pi*a*b**3/S(4)
|
||
|
|
||
|
e = Ellipse((a, b), 2, 6)
|
||
|
assert e.section_modulus() == (18*pi, 6*pi)
|
||
|
assert e.polar_second_moment_of_area() == 120*pi
|
||
|
|
||
|
e = Ellipse(Point(0, 0), 2, 2)
|
||
|
assert e.section_modulus() == (2*pi, 2*pi)
|
||
|
assert e.section_modulus(Point(2, 2)) == (2*pi, 2*pi)
|
||
|
assert e.section_modulus((2, 2)) == (2*pi, 2*pi)
|
||
|
|
||
|
|
||
|
def test_circumference():
|
||
|
M = Symbol('M')
|
||
|
m = Symbol('m')
|
||
|
assert Ellipse(Point(0, 0), M, m).circumference == 4 * M * elliptic_e((M ** 2 - m ** 2) / M**2)
|
||
|
|
||
|
assert Ellipse(Point(0, 0), 5, 4).circumference == 20 * elliptic_e(S(9) / 25)
|
||
|
|
||
|
# circle
|
||
|
assert Ellipse(None, 1, None, 0).circumference == 2*pi
|
||
|
|
||
|
# test numerically
|
||
|
assert abs(Ellipse(None, hradius=5, vradius=3).circumference.evalf(16) - 25.52699886339813) < 1e-10
|
||
|
|
||
|
|
||
|
def test_issue_15259():
|
||
|
assert Circle((1, 2), 0) == Point(1, 2)
|
||
|
|
||
|
|
||
|
def test_issue_15797_equals():
|
||
|
Ri = 0.024127189424130748
|
||
|
Ci = (0.0864931002830291, 0.0819863295239654)
|
||
|
A = Point(0, 0.0578591400998346)
|
||
|
c = Circle(Ci, Ri) # evaluated
|
||
|
assert c.is_tangent(c.tangent_lines(A)[0]) == True
|
||
|
assert c.center.x.is_Rational
|
||
|
assert c.center.y.is_Rational
|
||
|
assert c.radius.is_Rational
|
||
|
u = Circle(Ci, Ri, evaluate=False) # unevaluated
|
||
|
assert u.center.x.is_Float
|
||
|
assert u.center.y.is_Float
|
||
|
assert u.radius.is_Float
|
||
|
|
||
|
|
||
|
def test_auxiliary_circle():
|
||
|
x, y, a, b = symbols('x y a b')
|
||
|
e = Ellipse((x, y), a, b)
|
||
|
# the general result
|
||
|
assert e.auxiliary_circle() == Circle((x, y), Max(a, b))
|
||
|
# a special case where Ellipse is a Circle
|
||
|
assert Circle((3, 4), 8).auxiliary_circle() == Circle((3, 4), 8)
|
||
|
|
||
|
|
||
|
def test_director_circle():
|
||
|
x, y, a, b = symbols('x y a b')
|
||
|
e = Ellipse((x, y), a, b)
|
||
|
# the general result
|
||
|
assert e.director_circle() == Circle((x, y), sqrt(a**2 + b**2))
|
||
|
# a special case where Ellipse is a Circle
|
||
|
assert Circle((3, 4), 8).director_circle() == Circle((3, 4), 8*sqrt(2))
|
||
|
|
||
|
|
||
|
def test_evolute():
|
||
|
#ellipse centered at h,k
|
||
|
x, y, h, k = symbols('x y h k',real = True)
|
||
|
a, b = symbols('a b')
|
||
|
e = Ellipse(Point(h, k), a, b)
|
||
|
t1 = (e.hradius*(x - e.center.x))**Rational(2, 3)
|
||
|
t2 = (e.vradius*(y - e.center.y))**Rational(2, 3)
|
||
|
E = t1 + t2 - (e.hradius**2 - e.vradius**2)**Rational(2, 3)
|
||
|
assert e.evolute() == E
|
||
|
#Numerical Example
|
||
|
e = Ellipse(Point(1, 1), 6, 3)
|
||
|
t1 = (6*(x - 1))**Rational(2, 3)
|
||
|
t2 = (3*(y - 1))**Rational(2, 3)
|
||
|
E = t1 + t2 - (27)**Rational(2, 3)
|
||
|
assert e.evolute() == E
|
||
|
|
||
|
|
||
|
def test_svg():
|
||
|
e1 = Ellipse(Point(1, 0), 3, 2)
|
||
|
assert e1._svg(2, "#FFAAFF") == '<ellipse fill="#FFAAFF" stroke="#555555" stroke-width="4.0" opacity="0.6" cx="1.00000000000000" cy="0" rx="3.00000000000000" ry="2.00000000000000"/>'
|