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from sympy.core.numbers import (Float, Rational, oo, pi) | |
from sympy.core.singleton import S | |
from sympy.core.symbol import (Symbol, symbols) | |
from sympy.functions.elementary.complexes import Abs | |
from sympy.functions.elementary.miscellaneous import sqrt | |
from sympy.functions.elementary.trigonometric import (acos, cos, sin) | |
from sympy.functions.elementary.trigonometric import tan | |
from sympy.geometry import (Circle, Ellipse, GeometryError, Point, Point2D, | |
Polygon, Ray, RegularPolygon, Segment, Triangle, | |
are_similar, convex_hull, intersection, Line, Ray2D) | |
from sympy.testing.pytest import raises, slow, warns | |
from sympy.core.random import verify_numerically | |
from sympy.geometry.polygon import rad, deg | |
from sympy.integrals.integrals import integrate | |
from sympy.utilities.iterables import rotate_left | |
def feq(a, b): | |
"""Test if two floating point values are 'equal'.""" | |
t_float = Float("1.0E-10") | |
return -t_float < a - b < t_float | |
def test_polygon(): | |
x = Symbol('x', real=True) | |
y = Symbol('y', real=True) | |
q = Symbol('q', real=True) | |
u = Symbol('u', real=True) | |
v = Symbol('v', real=True) | |
w = Symbol('w', real=True) | |
x1 = Symbol('x1', real=True) | |
half = S.Half | |
a, b, c = Point(0, 0), Point(2, 0), Point(3, 3) | |
t = Triangle(a, b, c) | |
assert Polygon(Point(0, 0)) == Point(0, 0) | |
assert Polygon(a, Point(1, 0), b, c) == t | |
assert Polygon(Point(1, 0), b, c, a) == t | |
assert Polygon(b, c, a, Point(1, 0)) == t | |
# 2 "remove folded" tests | |
assert Polygon(a, Point(3, 0), b, c) == t | |
assert Polygon(a, b, Point(3, -1), b, c) == t | |
# remove multiple collinear points | |
assert Polygon(Point(-4, 15), Point(-11, 15), Point(-15, 15), | |
Point(-15, 33/5), Point(-15, -87/10), Point(-15, -15), | |
Point(-42/5, -15), Point(-2, -15), Point(7, -15), Point(15, -15), | |
Point(15, -3), Point(15, 10), Point(15, 15)) == \ | |
Polygon(Point(-15, -15), Point(15, -15), Point(15, 15), Point(-15, 15)) | |
p1 = Polygon( | |
Point(0, 0), Point(3, -1), | |
Point(6, 0), Point(4, 5), | |
Point(2, 3), Point(0, 3)) | |
p2 = Polygon( | |
Point(6, 0), Point(3, -1), | |
Point(0, 0), Point(0, 3), | |
Point(2, 3), Point(4, 5)) | |
p3 = Polygon( | |
Point(0, 0), Point(3, 0), | |
Point(5, 2), Point(4, 4)) | |
p4 = Polygon( | |
Point(0, 0), Point(4, 4), | |
Point(5, 2), Point(3, 0)) | |
p5 = Polygon( | |
Point(0, 0), Point(4, 4), | |
Point(0, 4)) | |
p6 = Polygon( | |
Point(-11, 1), Point(-9, 6.6), | |
Point(-4, -3), Point(-8.4, -8.7)) | |
p7 = Polygon( | |
Point(x, y), Point(q, u), | |
Point(v, w)) | |
p8 = Polygon( | |
Point(x, y), Point(v, w), | |
Point(q, u)) | |
p9 = Polygon( | |
Point(0, 0), Point(4, 4), | |
Point(3, 0), Point(5, 2)) | |
p10 = Polygon( | |
Point(0, 2), Point(2, 2), | |
Point(0, 0), Point(2, 0)) | |
p11 = Polygon(Point(0, 0), 1, n=3) | |
p12 = Polygon(Point(0, 0), 1, 0, n=3) | |
p13 = Polygon( | |
Point(0, 0),Point(8, 8), | |
Point(23, 20),Point(0, 20)) | |
p14 = Polygon(*rotate_left(p13.args, 1)) | |
r = Ray(Point(-9, 6.6), Point(-9, 5.5)) | |
# | |
# General polygon | |
# | |
assert p1 == p2 | |
assert len(p1.args) == 6 | |
assert len(p1.sides) == 6 | |
assert p1.perimeter == 5 + 2*sqrt(10) + sqrt(29) + sqrt(8) | |
assert p1.area == 22 | |
assert not p1.is_convex() | |
assert Polygon((-1, 1), (2, -1), (2, 1), (-1, -1), (3, 0) | |
).is_convex() is False | |
# ensure convex for both CW and CCW point specification | |
assert p3.is_convex() | |
assert p4.is_convex() | |
dict5 = p5.angles | |
assert dict5[Point(0, 0)] == pi / 4 | |
assert dict5[Point(0, 4)] == pi / 2 | |
assert p5.encloses_point(Point(x, y)) is None | |
assert p5.encloses_point(Point(1, 3)) | |
assert p5.encloses_point(Point(0, 0)) is False | |
assert p5.encloses_point(Point(4, 0)) is False | |
assert p1.encloses(Circle(Point(2.5, 2.5), 5)) is False | |
assert p1.encloses(Ellipse(Point(2.5, 2), 5, 6)) is False | |
assert p5.plot_interval('x') == [x, 0, 1] | |
assert p5.distance( | |
Polygon(Point(10, 10), Point(14, 14), Point(10, 14))) == 6 * sqrt(2) | |
assert p5.distance( | |
Polygon(Point(1, 8), Point(5, 8), Point(8, 12), Point(1, 12))) == 4 | |
with warns(UserWarning, \ | |
match="Polygons may intersect producing erroneous output"): | |
Polygon(Point(0, 0), Point(1, 0), Point(1, 1)).distance( | |
Polygon(Point(0, 0), Point(0, 1), Point(1, 1))) | |
assert hash(p5) == hash(Polygon(Point(0, 0), Point(4, 4), Point(0, 4))) | |
assert hash(p1) == hash(p2) | |
assert hash(p7) == hash(p8) | |
assert hash(p3) != hash(p9) | |
assert p5 == Polygon(Point(4, 4), Point(0, 4), Point(0, 0)) | |
assert Polygon(Point(4, 4), Point(0, 4), Point(0, 0)) in p5 | |
assert p5 != Point(0, 4) | |
assert Point(0, 1) in p5 | |
assert p5.arbitrary_point('t').subs(Symbol('t', real=True), 0) == \ | |
Point(0, 0) | |
raises(ValueError, lambda: Polygon( | |
Point(x, 0), Point(0, y), Point(x, y)).arbitrary_point('x')) | |
assert p6.intersection(r) == [Point(-9, Rational(-84, 13)), Point(-9, Rational(33, 5))] | |
assert p10.area == 0 | |
assert p11 == RegularPolygon(Point(0, 0), 1, 3, 0) | |
assert p11 == p12 | |
assert p11.vertices[0] == Point(1, 0) | |
assert p11.args[0] == Point(0, 0) | |
p11.spin(pi/2) | |
assert p11.vertices[0] == Point(0, 1) | |
# | |
# Regular polygon | |
# | |
p1 = RegularPolygon(Point(0, 0), 10, 5) | |
p2 = RegularPolygon(Point(0, 0), 5, 5) | |
raises(GeometryError, lambda: RegularPolygon(Point(0, 0), Point(0, | |
1), Point(1, 1))) | |
raises(GeometryError, lambda: RegularPolygon(Point(0, 0), 1, 2)) | |
raises(ValueError, lambda: RegularPolygon(Point(0, 0), 1, 2.5)) | |
assert p1 != p2 | |
assert p1.interior_angle == pi*Rational(3, 5) | |
assert p1.exterior_angle == pi*Rational(2, 5) | |
assert p2.apothem == 5*cos(pi/5) | |
assert p2.circumcenter == p1.circumcenter == Point(0, 0) | |
assert p1.circumradius == p1.radius == 10 | |
assert p2.circumcircle == Circle(Point(0, 0), 5) | |
assert p2.incircle == Circle(Point(0, 0), p2.apothem) | |
assert p2.inradius == p2.apothem == (5 * (1 + sqrt(5)) / 4) | |
p2.spin(pi / 10) | |
dict1 = p2.angles | |
assert dict1[Point(0, 5)] == 3 * pi / 5 | |
assert p1.is_convex() | |
assert p1.rotation == 0 | |
assert p1.encloses_point(Point(0, 0)) | |
assert p1.encloses_point(Point(11, 0)) is False | |
assert p2.encloses_point(Point(0, 4.9)) | |
p1.spin(pi/3) | |
assert p1.rotation == pi/3 | |
assert p1.vertices[0] == Point(5, 5*sqrt(3)) | |
for var in p1.args: | |
if isinstance(var, Point): | |
assert var == Point(0, 0) | |
else: | |
assert var in (5, 10, pi / 3) | |
assert p1 != Point(0, 0) | |
assert p1 != p5 | |
# while spin works in place (notice that rotation is 2pi/3 below) | |
# rotate returns a new object | |
p1_old = p1 | |
assert p1.rotate(pi/3) == RegularPolygon(Point(0, 0), 10, 5, pi*Rational(2, 3)) | |
assert p1 == p1_old | |
assert p1.area == (-250*sqrt(5) + 1250)/(4*tan(pi/5)) | |
assert p1.length == 20*sqrt(-sqrt(5)/8 + Rational(5, 8)) | |
assert p1.scale(2, 2) == \ | |
RegularPolygon(p1.center, p1.radius*2, p1._n, p1.rotation) | |
assert RegularPolygon((0, 0), 1, 4).scale(2, 3) == \ | |
Polygon(Point(2, 0), Point(0, 3), Point(-2, 0), Point(0, -3)) | |
assert repr(p1) == str(p1) | |
# | |
# Angles | |
# | |
angles = p4.angles | |
assert feq(angles[Point(0, 0)].evalf(), Float("0.7853981633974483")) | |
assert feq(angles[Point(4, 4)].evalf(), Float("1.2490457723982544")) | |
assert feq(angles[Point(5, 2)].evalf(), Float("1.8925468811915388")) | |
assert feq(angles[Point(3, 0)].evalf(), Float("2.3561944901923449")) | |
angles = p3.angles | |
assert feq(angles[Point(0, 0)].evalf(), Float("0.7853981633974483")) | |
assert feq(angles[Point(4, 4)].evalf(), Float("1.2490457723982544")) | |
assert feq(angles[Point(5, 2)].evalf(), Float("1.8925468811915388")) | |
assert feq(angles[Point(3, 0)].evalf(), Float("2.3561944901923449")) | |
# https://github.com/sympy/sympy/issues/24885 | |
interior_angles_sum = sum(p13.angles.values()) | |
assert feq(interior_angles_sum, (len(p13.angles) - 2)*pi ) | |
interior_angles_sum = sum(p14.angles.values()) | |
assert feq(interior_angles_sum, (len(p14.angles) - 2)*pi ) | |
# | |
# Triangle | |
# | |
p1 = Point(0, 0) | |
p2 = Point(5, 0) | |
p3 = Point(0, 5) | |
t1 = Triangle(p1, p2, p3) | |
t2 = Triangle(p1, p2, Point(Rational(5, 2), sqrt(Rational(75, 4)))) | |
t3 = Triangle(p1, Point(x1, 0), Point(0, x1)) | |
s1 = t1.sides | |
assert Triangle(p1, p2, p1) == Polygon(p1, p2, p1) == Segment(p1, p2) | |
raises(GeometryError, lambda: Triangle(Point(0, 0))) | |
# Basic stuff | |
assert Triangle(p1, p1, p1) == p1 | |
assert Triangle(p2, p2*2, p2*3) == Segment(p2, p2*3) | |
assert t1.area == Rational(25, 2) | |
assert t1.is_right() | |
assert t2.is_right() is False | |
assert t3.is_right() | |
assert p1 in t1 | |
assert t1.sides[0] in t1 | |
assert Segment((0, 0), (1, 0)) in t1 | |
assert Point(5, 5) not in t2 | |
assert t1.is_convex() | |
assert feq(t1.angles[p1].evalf(), pi.evalf()/2) | |
assert t1.is_equilateral() is False | |
assert t2.is_equilateral() | |
assert t3.is_equilateral() is False | |
assert are_similar(t1, t2) is False | |
assert are_similar(t1, t3) | |
assert are_similar(t2, t3) is False | |
assert t1.is_similar(Point(0, 0)) is False | |
assert t1.is_similar(t2) is False | |
# Bisectors | |
bisectors = t1.bisectors() | |
assert bisectors[p1] == Segment( | |
p1, Point(Rational(5, 2), Rational(5, 2))) | |
assert t2.bisectors()[p2] == Segment( | |
Point(5, 0), Point(Rational(5, 4), 5*sqrt(3)/4)) | |
p4 = Point(0, x1) | |
assert t3.bisectors()[p4] == Segment(p4, Point(x1*(sqrt(2) - 1), 0)) | |
ic = (250 - 125*sqrt(2))/50 | |
assert t1.incenter == Point(ic, ic) | |
# Inradius | |
assert t1.inradius == t1.incircle.radius == 5 - 5*sqrt(2)/2 | |
assert t2.inradius == t2.incircle.radius == 5*sqrt(3)/6 | |
assert t3.inradius == t3.incircle.radius == x1**2/((2 + sqrt(2))*Abs(x1)) | |
# Exradius | |
assert t1.exradii[t1.sides[2]] == 5*sqrt(2)/2 | |
# Excenters | |
assert t1.excenters[t1.sides[2]] == Point2D(25*sqrt(2), -5*sqrt(2)/2) | |
# Circumcircle | |
assert t1.circumcircle.center == Point(2.5, 2.5) | |
# Medians + Centroid | |
m = t1.medians | |
assert t1.centroid == Point(Rational(5, 3), Rational(5, 3)) | |
assert m[p1] == Segment(p1, Point(Rational(5, 2), Rational(5, 2))) | |
assert t3.medians[p1] == Segment(p1, Point(x1/2, x1/2)) | |
assert intersection(m[p1], m[p2], m[p3]) == [t1.centroid] | |
assert t1.medial == Triangle(Point(2.5, 0), Point(0, 2.5), Point(2.5, 2.5)) | |
# Nine-point circle | |
assert t1.nine_point_circle == Circle(Point(2.5, 0), | |
Point(0, 2.5), Point(2.5, 2.5)) | |
assert t1.nine_point_circle == Circle(Point(0, 0), | |
Point(0, 2.5), Point(2.5, 2.5)) | |
# Perpendicular | |
altitudes = t1.altitudes | |
assert altitudes[p1] == Segment(p1, Point(Rational(5, 2), Rational(5, 2))) | |
assert altitudes[p2].equals(s1[0]) | |
assert altitudes[p3] == s1[2] | |
assert t1.orthocenter == p1 | |
t = S('''Triangle( | |
Point(100080156402737/5000000000000, 79782624633431/500000000000), | |
Point(39223884078253/2000000000000, 156345163124289/1000000000000), | |
Point(31241359188437/1250000000000, 338338270939941/1000000000000000))''') | |
assert t.orthocenter == S('''Point(-780660869050599840216997''' | |
'''79471538701955848721853/80368430960602242240789074233100000000000000,''' | |
'''20151573611150265741278060334545897615974257/16073686192120448448157''' | |
'''8148466200000000000)''') | |
# Ensure | |
assert len(intersection(*bisectors.values())) == 1 | |
assert len(intersection(*altitudes.values())) == 1 | |
assert len(intersection(*m.values())) == 1 | |
# Distance | |
p1 = Polygon( | |
Point(0, 0), Point(1, 0), | |
Point(1, 1), Point(0, 1)) | |
p2 = Polygon( | |
Point(0, Rational(5)/4), Point(1, Rational(5)/4), | |
Point(1, Rational(9)/4), Point(0, Rational(9)/4)) | |
p3 = Polygon( | |
Point(1, 2), Point(2, 2), | |
Point(2, 1)) | |
p4 = Polygon( | |
Point(1, 1), Point(Rational(6)/5, 1), | |
Point(1, Rational(6)/5)) | |
pt1 = Point(half, half) | |
pt2 = Point(1, 1) | |
'''Polygon to Point''' | |
assert p1.distance(pt1) == half | |
assert p1.distance(pt2) == 0 | |
assert p2.distance(pt1) == Rational(3)/4 | |
assert p3.distance(pt2) == sqrt(2)/2 | |
'''Polygon to Polygon''' | |
# p1.distance(p2) emits a warning | |
with warns(UserWarning, \ | |
match="Polygons may intersect producing erroneous output"): | |
assert p1.distance(p2) == half/2 | |
assert p1.distance(p3) == sqrt(2)/2 | |
# p3.distance(p4) emits a warning | |
with warns(UserWarning, \ | |
match="Polygons may intersect producing erroneous output"): | |
assert p3.distance(p4) == (sqrt(2)/2 - sqrt(Rational(2)/25)/2) | |
def test_convex_hull(): | |
p = [Point(-5, -1), Point(-2, 1), Point(-2, -1), Point(-1, -3), \ | |
Point(0, 0), Point(1, 1), Point(2, 2), Point(2, -1), Point(3, 1), \ | |
Point(4, -1), Point(6, 2)] | |
ch = Polygon(p[0], p[3], p[9], p[10], p[6], p[1]) | |
#test handling of duplicate points | |
p.append(p[3]) | |
#more than 3 collinear points | |
another_p = [Point(-45, -85), Point(-45, 85), Point(-45, 26), \ | |
Point(-45, -24)] | |
ch2 = Segment(another_p[0], another_p[1]) | |
assert convex_hull(*another_p) == ch2 | |
assert convex_hull(*p) == ch | |
assert convex_hull(p[0]) == p[0] | |
assert convex_hull(p[0], p[1]) == Segment(p[0], p[1]) | |
# no unique points | |
assert convex_hull(*[p[-1]]*3) == p[-1] | |
# collection of items | |
assert convex_hull(*[Point(0, 0), \ | |
Segment(Point(1, 0), Point(1, 1)), \ | |
RegularPolygon(Point(2, 0), 2, 4)]) == \ | |
Polygon(Point(0, 0), Point(2, -2), Point(4, 0), Point(2, 2)) | |
def test_encloses(): | |
# square with a dimpled left side | |
s = Polygon(Point(0, 0), Point(1, 0), Point(1, 1), Point(0, 1), \ | |
Point(S.Half, S.Half)) | |
# the following is True if the polygon isn't treated as closing on itself | |
assert s.encloses(Point(0, S.Half)) is False | |
assert s.encloses(Point(S.Half, S.Half)) is False # it's a vertex | |
assert s.encloses(Point(Rational(3, 4), S.Half)) is True | |
def test_triangle_kwargs(): | |
assert Triangle(sss=(3, 4, 5)) == \ | |
Triangle(Point(0, 0), Point(3, 0), Point(3, 4)) | |
assert Triangle(asa=(30, 2, 30)) == \ | |
Triangle(Point(0, 0), Point(2, 0), Point(1, sqrt(3)/3)) | |
assert Triangle(sas=(1, 45, 2)) == \ | |
Triangle(Point(0, 0), Point(2, 0), Point(sqrt(2)/2, sqrt(2)/2)) | |
assert Triangle(sss=(1, 2, 5)) is None | |
assert deg(rad(180)) == 180 | |
def test_transform(): | |
pts = [Point(0, 0), Point(S.Half, Rational(1, 4)), Point(1, 1)] | |
pts_out = [Point(-4, -10), Point(-3, Rational(-37, 4)), Point(-2, -7)] | |
assert Triangle(*pts).scale(2, 3, (4, 5)) == Triangle(*pts_out) | |
assert RegularPolygon((0, 0), 1, 4).scale(2, 3, (4, 5)) == \ | |
Polygon(Point(-2, -10), Point(-4, -7), Point(-6, -10), Point(-4, -13)) | |
# Checks for symmetric scaling | |
assert RegularPolygon((0, 0), 1, 4).scale(2, 2) == \ | |
RegularPolygon(Point2D(0, 0), 2, 4, 0) | |
def test_reflect(): | |
x = Symbol('x', real=True) | |
y = Symbol('y', real=True) | |
b = Symbol('b') | |
m = Symbol('m') | |
l = Line((0, b), slope=m) | |
p = Point(x, y) | |
r = p.reflect(l) | |
dp = l.perpendicular_segment(p).length | |
dr = l.perpendicular_segment(r).length | |
assert verify_numerically(dp, dr) | |
assert Polygon((1, 0), (2, 0), (2, 2)).reflect(Line((3, 0), slope=oo)) \ | |
== Triangle(Point(5, 0), Point(4, 0), Point(4, 2)) | |
assert Polygon((1, 0), (2, 0), (2, 2)).reflect(Line((0, 3), slope=oo)) \ | |
== Triangle(Point(-1, 0), Point(-2, 0), Point(-2, 2)) | |
assert Polygon((1, 0), (2, 0), (2, 2)).reflect(Line((0, 3), slope=0)) \ | |
== Triangle(Point(1, 6), Point(2, 6), Point(2, 4)) | |
assert Polygon((1, 0), (2, 0), (2, 2)).reflect(Line((3, 0), slope=0)) \ | |
== Triangle(Point(1, 0), Point(2, 0), Point(2, -2)) | |
def test_bisectors(): | |
p1, p2, p3 = Point(0, 0), Point(1, 0), Point(0, 1) | |
p = Polygon(Point(0, 0), Point(2, 0), Point(1, 1), Point(0, 3)) | |
q = Polygon(Point(1, 0), Point(2, 0), Point(3, 3), Point(-1, 5)) | |
poly = Polygon(Point(3, 4), Point(0, 0), Point(8, 7), Point(-1, 1), Point(19, -19)) | |
t = Triangle(p1, p2, p3) | |
assert t.bisectors()[p2] == Segment(Point(1, 0), Point(0, sqrt(2) - 1)) | |
assert p.bisectors()[Point2D(0, 3)] == Ray2D(Point2D(0, 3), \ | |
Point2D(sin(acos(2*sqrt(5)/5)/2), 3 - cos(acos(2*sqrt(5)/5)/2))) | |
assert q.bisectors()[Point2D(-1, 5)] == \ | |
Ray2D(Point2D(-1, 5), Point2D(-1 + sqrt(29)*(5*sin(acos(9*sqrt(145)/145)/2) + \ | |
2*cos(acos(9*sqrt(145)/145)/2))/29, sqrt(29)*(-5*cos(acos(9*sqrt(145)/145)/2) + \ | |
2*sin(acos(9*sqrt(145)/145)/2))/29 + 5)) | |
assert poly.bisectors()[Point2D(-1, 1)] == Ray2D(Point2D(-1, 1), \ | |
Point2D(-1 + sin(acos(sqrt(26)/26)/2 + pi/4), 1 - sin(-acos(sqrt(26)/26)/2 + pi/4))) | |
def test_incenter(): | |
assert Triangle(Point(0, 0), Point(1, 0), Point(0, 1)).incenter \ | |
== Point(1 - sqrt(2)/2, 1 - sqrt(2)/2) | |
def test_inradius(): | |
assert Triangle(Point(0, 0), Point(4, 0), Point(0, 3)).inradius == 1 | |
def test_incircle(): | |
assert Triangle(Point(0, 0), Point(2, 0), Point(0, 2)).incircle \ | |
== Circle(Point(2 - sqrt(2), 2 - sqrt(2)), 2 - sqrt(2)) | |
def test_exradii(): | |
t = Triangle(Point(0, 0), Point(6, 0), Point(0, 2)) | |
assert t.exradii[t.sides[2]] == (-2 + sqrt(10)) | |
def test_medians(): | |
t = Triangle(Point(0, 0), Point(1, 0), Point(0, 1)) | |
assert t.medians[Point(0, 0)] == Segment(Point(0, 0), Point(S.Half, S.Half)) | |
def test_medial(): | |
assert Triangle(Point(0, 0), Point(1, 0), Point(0, 1)).medial \ | |
== Triangle(Point(S.Half, 0), Point(S.Half, S.Half), Point(0, S.Half)) | |
def test_nine_point_circle(): | |
assert Triangle(Point(0, 0), Point(1, 0), Point(0, 1)).nine_point_circle \ | |
== Circle(Point2D(Rational(1, 4), Rational(1, 4)), sqrt(2)/4) | |
def test_eulerline(): | |
assert Triangle(Point(0, 0), Point(1, 0), Point(0, 1)).eulerline \ | |
== Line(Point2D(0, 0), Point2D(S.Half, S.Half)) | |
assert Triangle(Point(0, 0), Point(10, 0), Point(5, 5*sqrt(3))).eulerline \ | |
== Point2D(5, 5*sqrt(3)/3) | |
assert Triangle(Point(4, -6), Point(4, -1), Point(-3, 3)).eulerline \ | |
== Line(Point2D(Rational(64, 7), 3), Point2D(Rational(-29, 14), Rational(-7, 2))) | |
def test_intersection(): | |
poly1 = Triangle(Point(0, 0), Point(1, 0), Point(0, 1)) | |
poly2 = Polygon(Point(0, 1), Point(-5, 0), | |
Point(0, -4), Point(0, Rational(1, 5)), | |
Point(S.Half, -0.1), Point(1, 0), Point(0, 1)) | |
assert poly1.intersection(poly2) == [Point2D(Rational(1, 3), 0), | |
Segment(Point(0, Rational(1, 5)), Point(0, 0)), | |
Segment(Point(1, 0), Point(0, 1))] | |
assert poly2.intersection(poly1) == [Point(Rational(1, 3), 0), | |
Segment(Point(0, 0), Point(0, Rational(1, 5))), | |
Segment(Point(1, 0), Point(0, 1))] | |
assert poly1.intersection(Point(0, 0)) == [Point(0, 0)] | |
assert poly1.intersection(Point(-12, -43)) == [] | |
assert poly2.intersection(Line((-12, 0), (12, 0))) == [Point(-5, 0), | |
Point(0, 0), Point(Rational(1, 3), 0), Point(1, 0)] | |
assert poly2.intersection(Line((-12, 12), (12, 12))) == [] | |
assert poly2.intersection(Ray((-3, 4), (1, 0))) == [Segment(Point(1, 0), | |
Point(0, 1))] | |
assert poly2.intersection(Circle((0, -1), 1)) == [Point(0, -2), | |
Point(0, 0)] | |
assert poly1.intersection(poly1) == [Segment(Point(0, 0), Point(1, 0)), | |
Segment(Point(0, 1), Point(0, 0)), Segment(Point(1, 0), Point(0, 1))] | |
assert poly2.intersection(poly2) == [Segment(Point(-5, 0), Point(0, -4)), | |
Segment(Point(0, -4), Point(0, Rational(1, 5))), | |
Segment(Point(0, Rational(1, 5)), Point(S.Half, Rational(-1, 10))), | |
Segment(Point(0, 1), Point(-5, 0)), | |
Segment(Point(S.Half, Rational(-1, 10)), Point(1, 0)), | |
Segment(Point(1, 0), Point(0, 1))] | |
assert poly2.intersection(Triangle(Point(0, 1), Point(1, 0), Point(-1, 1))) \ | |
== [Point(Rational(-5, 7), Rational(6, 7)), Segment(Point2D(0, 1), Point(1, 0))] | |
assert poly1.intersection(RegularPolygon((-12, -15), 3, 3)) == [] | |
def test_parameter_value(): | |
t = Symbol('t') | |
sq = Polygon((0, 0), (0, 1), (1, 1), (1, 0)) | |
assert sq.parameter_value((0.5, 1), t) == {t: Rational(3, 8)} | |
q = Polygon((0, 0), (2, 1), (2, 4), (4, 0)) | |
assert q.parameter_value((4, 0), t) == {t: -6 + 3*sqrt(5)} # ~= 0.708 | |
raises(ValueError, lambda: sq.parameter_value((5, 6), t)) | |
raises(ValueError, lambda: sq.parameter_value(Circle(Point(0, 0), 1), t)) | |
def test_issue_12966(): | |
poly = Polygon(Point(0, 0), Point(0, 10), Point(5, 10), Point(5, 5), | |
Point(10, 5), Point(10, 0)) | |
t = Symbol('t') | |
pt = poly.arbitrary_point(t) | |
DELTA = 5/poly.perimeter | |
assert [pt.subs(t, DELTA*i) for i in range(int(1/DELTA))] == [ | |
Point(0, 0), Point(0, 5), Point(0, 10), Point(5, 10), | |
Point(5, 5), Point(10, 5), Point(10, 0), Point(5, 0)] | |
def test_second_moment_of_area(): | |
x, y = symbols('x, y') | |
# triangle | |
p1, p2, p3 = [(0, 0), (4, 0), (0, 2)] | |
p = (0, 0) | |
# equation of hypotenuse | |
eq_y = (1-x/4)*2 | |
I_yy = integrate((x**2) * (integrate(1, (y, 0, eq_y))), (x, 0, 4)) | |
I_xx = integrate(1 * (integrate(y**2, (y, 0, eq_y))), (x, 0, 4)) | |
I_xy = integrate(x * (integrate(y, (y, 0, eq_y))), (x, 0, 4)) | |
triangle = Polygon(p1, p2, p3) | |
assert (I_xx - triangle.second_moment_of_area(p)[0]) == 0 | |
assert (I_yy - triangle.second_moment_of_area(p)[1]) == 0 | |
assert (I_xy - triangle.second_moment_of_area(p)[2]) == 0 | |
# rectangle | |
p1, p2, p3, p4=[(0, 0), (4, 0), (4, 2), (0, 2)] | |
I_yy = integrate((x**2) * integrate(1, (y, 0, 2)), (x, 0, 4)) | |
I_xx = integrate(1 * integrate(y**2, (y, 0, 2)), (x, 0, 4)) | |
I_xy = integrate(x * integrate(y, (y, 0, 2)), (x, 0, 4)) | |
rectangle = Polygon(p1, p2, p3, p4) | |
assert (I_xx - rectangle.second_moment_of_area(p)[0]) == 0 | |
assert (I_yy - rectangle.second_moment_of_area(p)[1]) == 0 | |
assert (I_xy - rectangle.second_moment_of_area(p)[2]) == 0 | |
r = RegularPolygon(Point(0, 0), 5, 3) | |
assert r.second_moment_of_area() == (1875*sqrt(3)/S(32), 1875*sqrt(3)/S(32), 0) | |
def test_first_moment(): | |
a, b = symbols('a, b', positive=True) | |
# rectangle | |
p1 = Polygon((0, 0), (a, 0), (a, b), (0, b)) | |
assert p1.first_moment_of_area() == (a*b**2/8, a**2*b/8) | |
assert p1.first_moment_of_area((a/3, b/4)) == (-3*a*b**2/32, -a**2*b/9) | |
p1 = Polygon((0, 0), (40, 0), (40, 30), (0, 30)) | |
assert p1.first_moment_of_area() == (4500, 6000) | |
# triangle | |
p2 = Polygon((0, 0), (a, 0), (a/2, b)) | |
assert p2.first_moment_of_area() == (4*a*b**2/81, a**2*b/24) | |
assert p2.first_moment_of_area((a/8, b/6)) == (-25*a*b**2/648, -5*a**2*b/768) | |
p2 = Polygon((0, 0), (12, 0), (12, 30)) | |
assert p2.first_moment_of_area() == (S(1600)/3, -S(640)/3) | |
def test_section_modulus_and_polar_second_moment_of_area(): | |
a, b = symbols('a, b', positive=True) | |
x, y = symbols('x, y') | |
rectangle = Polygon((0, b), (0, 0), (a, 0), (a, b)) | |
assert rectangle.section_modulus(Point(x, y)) == (a*b**3/12/(-b/2 + y), a**3*b/12/(-a/2 + x)) | |
assert rectangle.polar_second_moment_of_area() == a**3*b/12 + a*b**3/12 | |
convex = RegularPolygon((0, 0), 1, 6) | |
assert convex.section_modulus() == (Rational(5, 8), sqrt(3)*Rational(5, 16)) | |
assert convex.polar_second_moment_of_area() == 5*sqrt(3)/S(8) | |
concave = Polygon((0, 0), (1, 8), (3, 4), (4, 6), (7, 1)) | |
assert concave.section_modulus() == (Rational(-6371, 429), Rational(-9778, 519)) | |
assert concave.polar_second_moment_of_area() == Rational(-38669, 252) | |
def test_cut_section(): | |
# concave polygon | |
p = Polygon((-1, -1), (1, Rational(5, 2)), (2, 1), (3, Rational(5, 2)), (4, 2), (5, 3), (-1, 3)) | |
l = Line((0, 0), (Rational(9, 2), 3)) | |
p1 = p.cut_section(l)[0] | |
p2 = p.cut_section(l)[1] | |
assert p1 == Polygon( | |
Point2D(Rational(-9, 13), Rational(-6, 13)), Point2D(1, Rational(5, 2)), Point2D(Rational(24, 13), Rational(16, 13)), | |
Point2D(Rational(12, 5), Rational(8, 5)), Point2D(3, Rational(5, 2)), Point2D(Rational(24, 7), Rational(16, 7)), | |
Point2D(Rational(9, 2), 3), Point2D(-1, 3), Point2D(-1, Rational(-2, 3))) | |
assert p2 == Polygon(Point2D(-1, -1), Point2D(Rational(-9, 13), Rational(-6, 13)), Point2D(Rational(24, 13), Rational(16, 13)), | |
Point2D(2, 1), Point2D(Rational(12, 5), Rational(8, 5)), Point2D(Rational(24, 7), Rational(16, 7)), Point2D(4, 2), Point2D(5, 3), | |
Point2D(Rational(9, 2), 3), Point2D(-1, Rational(-2, 3))) | |
# convex polygon | |
p = RegularPolygon(Point2D(0, 0), 6, 6) | |
s = p.cut_section(Line((0, 0), slope=1)) | |
assert s[0] == Polygon(Point2D(-3*sqrt(3) + 9, -3*sqrt(3) + 9), Point2D(3, 3*sqrt(3)), | |
Point2D(-3, 3*sqrt(3)), Point2D(-6, 0), Point2D(-9 + 3*sqrt(3), -9 + 3*sqrt(3))) | |
assert s[1] == Polygon(Point2D(6, 0), Point2D(-3*sqrt(3) + 9, -3*sqrt(3) + 9), | |
Point2D(-9 + 3*sqrt(3), -9 + 3*sqrt(3)), Point2D(-3, -3*sqrt(3)), Point2D(3, -3*sqrt(3))) | |
# case where line does not intersects but coincides with the edge of polygon | |
a, b = 20, 10 | |
t1, t2, t3, t4 = [(0, b), (0, 0), (a, 0), (a, b)] | |
p = Polygon(t1, t2, t3, t4) | |
p1, p2 = p.cut_section(Line((0, b), slope=0)) | |
assert p1 == None | |
assert p2 == Polygon(Point2D(0, 10), Point2D(0, 0), Point2D(20, 0), Point2D(20, 10)) | |
p3, p4 = p.cut_section(Line((0, 0), slope=0)) | |
assert p3 == Polygon(Point2D(0, 10), Point2D(0, 0), Point2D(20, 0), Point2D(20, 10)) | |
assert p4 == None | |
# case where the line does not intersect with a polygon at all | |
raises(ValueError, lambda: p.cut_section(Line((0, a), slope=0))) | |
def test_type_of_triangle(): | |
# Isoceles triangle | |
p1 = Polygon(Point(0, 0), Point(5, 0), Point(2, 4)) | |
assert p1.is_isosceles() == True | |
assert p1.is_scalene() == False | |
assert p1.is_equilateral() == False | |
# Scalene triangle | |
p2 = Polygon (Point(0, 0), Point(0, 2), Point(4, 0)) | |
assert p2.is_isosceles() == False | |
assert p2.is_scalene() == True | |
assert p2.is_equilateral() == False | |
# Equilateral triagle | |
p3 = Polygon(Point(0, 0), Point(6, 0), Point(3, sqrt(27))) | |
assert p3.is_isosceles() == True | |
assert p3.is_scalene() == False | |
assert p3.is_equilateral() == True | |
def test_do_poly_distance(): | |
# Non-intersecting polygons | |
square1 = Polygon (Point(0, 0), Point(0, 1), Point(1, 1), Point(1, 0)) | |
triangle1 = Polygon(Point(1, 2), Point(2, 2), Point(2, 1)) | |
assert square1._do_poly_distance(triangle1) == sqrt(2)/2 | |
# Polygons which sides intersect | |
square2 = Polygon(Point(1, 0), Point(2, 0), Point(2, 1), Point(1, 1)) | |
with warns(UserWarning, \ | |
match="Polygons may intersect producing erroneous output", test_stacklevel=False): | |
assert square1._do_poly_distance(square2) == 0 | |
# Polygons which bodies intersect | |
triangle2 = Polygon(Point(0, -1), Point(2, -1), Point(S.Half, S.Half)) | |
with warns(UserWarning, \ | |
match="Polygons may intersect producing erroneous output", test_stacklevel=False): | |
assert triangle2._do_poly_distance(square1) == 0 | |