Example #1
0
    def run_tests(self):

        from sage.all import CIF, RIF
        
        pts = [
            FinitePoint(CIF(1.2,  5.2), RIF(2.4)),
            FinitePoint(CIF(3.2,  4.2), RIF(1.4)),
            FinitePoint(CIF(2.2, -3.2), RIF(0.4)) ]

        t = FiniteTriangle(pts)

        for i in range(3):
            m = t.reflections[1][i]
            if not abs(m[0,0] + m[1,1]) < 1e-6:
                raise Exception('%r' % m)

        for i, pt in enumerate(pts):
            if not pt.translate_PGL(t.reflections[0][i]).dist(pt) < 1e-6:
                raise Exception("Vertex reflection not fixing")

            for j in range(3):
                if i != j:
                    pt_t = pt.translate_PGL(t.reflections[1][j])
                    if not pt_t.dist(pt) < 1e-6:
                        raise Exception(
                            "Side reflection not fixing %r %r %r" % (
                                pt, pt_t, pt_t.dist(pt)))

            if not pt.translate_PGL(t.reflections[2][0]).dist(pt) < 1e-6:
                raise Exception("Plane reflection not fixing %r %r %r" % (
                        pt, pt.translate_PGL(t.reflections[2][0]),
                        pt.translate_PGL(t.reflections[2][0]).dist(pt)))
Example #2
0
    def test_plane_reflection(self):

        from sage.all import CIF

        zs = [CIF(1.2, 3.2), CIF(4.2, 2.2), CIF(-1.1, 3.5)]
        pts = [ProjectivePoint(z) for z in zs]

        m = PlaneReflection.from_three_projective_points(*pts)
        if not m.isOrientationReversing:
            raise Exception("Orientation preserving not expected")

        for pt in pts:
            # They should be fixed
            if not pt.translate(m).is_close_to(pt):
                raise Exception("Point not fixed by plane reflection")
Example #3
0
def _get_projective_endpoints_of_line(vertices, vertex_reflections):
    e = PrimitivesDistanceEngine([0,0], vertex_reflections)
    
    endpoints, h = e.fixed_projective_points_or_bounding_halfsphere()
    
    if not endpoints:
        raise Exception("Blah")

    CIF = vertices[0].z.parent()
    
    for i in range(1, 4):
        m = _adjoint2(
            ProjectivePoint.matrix_taking_0_1_inf_to_given_points(
                endpoints[0], ProjectivePoint(CIF(i)), endpoints[1]))
        if m.det().abs() > 0:
            try:
                vs = [ v.translate_PGL(m) for v in vertices ]
            except:
                continue
            
            if not all([not v.z != 0 for v in vs]):
                raise Exception("Images of vertices supposed to be "
                                "on vertical line.")

            if vs[0].t > vs[1].t:
                return endpoints[::-1]
            if vs[0].t < vs[1].t:
                return endpoints
    
    raise Exception("Could not find endpoints")
Example #4
0
    def test_point_reflection(self):
        from sage.all import RIF, CIF

        pt = FinitePoint(CIF(1.3, 4.2), RIF(2.6))
        pt2 = PointReflection.to_finite_point(
            PointReflection.from_finite_point(pt))

        if not pt.dist(pt2) < 1e-6:
            raise Exception("%r %r %r" % (pt, pt2, pt.dist(pt2)))
    def test_plane_line(self):
        from sage.all import CIF

        pts_plane = [
            ProjectivePoint(CIF(-1)),
            ProjectivePoint(CIF(1)),
            ProjectivePoint(CIF(0, 1))
        ]
        pts_line = [
            ProjectivePoint(CIF(sage.all.e)),
            ProjectivePoint(CIF(-sage.all.e))
        ]
        plane = PlaneReflection.from_three_projective_points(*pts_plane)
        line = LineReflection.from_two_projective_points(*pts_line)

        pp = PlaneLineDistanceEngine(plane, line)

        if not abs(1 - pp.dist()) < 1e-10:
            raise Exception("Wrong distance: %r" % pp.dist())
Example #6
0
    def matrix_multiplication_works(self, matrices):
        from sage.all import RIF, CIF, prod

        a = FinitePoint(CIF(RIF(3.5), RIF(-3.0)), RIF(8.5))

        a0 = a.translate_PGL(prod(matrices))
        for m in matrices[::-1]:
            a = a.translate_PGL(m)

        if not a.dist(a0) < 1e-6:
            raise Exception("Distance %r" % a.dist(a0))
def _intersection_of_two_lines_from_endpoints(pts_line1, pts_line2):
    m = matrix_taking_0_1_inf_to_given_points(pts_line1[0], pts_line1[1],
                                              pts_line2[0])

    z = pts_line2[1].translate(_adjoint2(m)).as_ideal_point()
    if z == Infinity:
        raise Exception("Unexpected Infinity")
    CIF = z.parent()
    zReal = z.real()
    t = (zReal * 2 - 1).sqrt() / 2

    return FinitePoint(CIF(zReal), t).translate_PGL(m)
Example #8
0
    def images_have_same_distance(self, m):
        from sage.rings.real_mpfi import RealIntervalFieldElement

        from sage.all import RIF, CIF
        a = FinitePoint(CIF(RIF(3.5), RIF(-3.0)), RIF(8.5))
        b = FinitePoint(CIF(RIF(4.5), RIF(-4.5)), RIF(9.6))

        d_before = a.dist(b)

        a = a.translate_PGL(m)
        b = b.translate_PGL(m)

        d_after = a.dist(b)

        if not isinstance(d_before, RealIntervalFieldElement):
            raise Exception("Expected distance to be RIF")
        if not isinstance(d_after, RealIntervalFieldElement):
            raise Exception("Expected distance to be RIF")

        if not abs(d_before - d_after) < 1e-12:
            raise Exception("Distance changed %r %r" % (d_before, d_after))
Example #9
0
    def compute_inradius_and_incenter(projectivePoints):
        """
        Radius and center of an inscribed sphere of an ideal
        tetrahedron. The function expects four
        :class:`ProjectivePoint` and returns a pair of a
        ``RealIntervalField`` element and a :class:`FinitePoint`::
        
            sage: from sage.all import *
            sage: z0 = ProjectivePoint(CIF(0), inverted = True)
            sage: z1 = ProjectivePoint(CIF(0))
            sage: z2 = ProjectivePoint(CIF(0, RIF(3.4142, 3.4143)))
            sage: z3 = ProjectivePoint(CIF(RIF(3.4142, 3.4143), 0))
            sage: ProjectivePoint.compute_inradius_and_incenter([z0, z1, z2, z3]) # doctest: +NUMERIC12
            (0.317?, FinitePoint(1.0000? + 1.0000?*I, 3.108?))

        """
        
        # We assume that one of the points is at infinity.
        if not len(projectivePoints) == 4:
            raise Exception("Expecting 4 ProjectivePoint's")
        
        pointClosestToInf = -1
        distToInf = sage.all.Infinity
    
        for i, projectivePoint in enumerate(projectivePoints):
            if projectivePoint.inverted:
                d = abs(projectivePoint.z).upper()
                if d < distToInf:
                    pointClosestToInf = i
                    distToInf = d

        if pointClosestToInf == -1:
            return compute_inradius_and_incenter(
                [ projectivePoint.as_ideal_point()
                  for projectivePoint in projectivePoints ])
        
        zInv = projectivePoints[pointClosestToInf].z
        CIF = zInv.parent()
        gl_matrix = matrix(CIF, [[ 1, 0], [-zInv, 1]])
        sl_matrix = CIF(sage.all.I) * gl_matrix
        inv_sl_matrix = _adjoint2(sl_matrix)
        
        transformedIdealPoints = [
            p.translate(gl_matrix).as_ideal_point()
            for i, p in enumerate(projectivePoints)
            if i != pointClosestToInf ]
        
        inradius, transformedInCenter = (
            _compute_inradius_and_incenter_with_one_point_at_infinity(
                transformedIdealPoints))
                    
        return inradius, transformedInCenter.translate_PSL(inv_sl_matrix)
    def test_plane_point(self):
        from sage.all import RealIntervalField, ComplexIntervalField
        CIF = ComplexIntervalField(120)
        RIF = RealIntervalField(120)

        pts = [
            ProjectivePoint(CIF(1.01)),
            ProjectivePoint(CIF(3)),
            ProjectivePoint(CIF(2, 1))
        ]

        pt = FinitePoint(CIF(2, 5), RIF(3))

        plane = PlaneReflection.from_three_projective_points(*pts)

        p = PlanePointDistanceEngine(plane,
                                     PointReflection.from_finite_point(pt))
        e = p.endpoint()

        if not abs(p.dist() - pt.dist(e)) < 1e-20:
            raise Exception("Distance incorrect %r %r" %
                            (p.dist(), pt.dist(e)))
Example #11
0
    def compute_incenter_of_triangle(projectivePoints):
        """
        Computes incenter of an ideal triangle. The function expects three
        :class:`ProjectivePoint` and returns a :class:`FinitePoint`::

            sage: from sage.all import *
            sage: z0 = ProjectivePoint(CIF(0), inverted = True)
            sage: z1 = ProjectivePoint(CIF(0))
            sage: z2 = ProjectivePoint(CIF(1))
            sage: ProjectivePoint.compute_incenter_of_triangle([z0, z1, z2])
            FinitePoint(0.50000000000000000?, 0.866025403784439?)

        """
        
        if not len(projectivePoints) == 3:
            raise ValueError("Expecting 3 ProjectivePoint's")
        
        pointClosestToInf = -1
        distToInf = sage.all.Infinity
    
        for i, projectivePoint in enumerate(projectivePoints):
            if projectivePoint.inverted:
                d = abs(projectivePoint.z).upper()
                if d < distToInf:
                    pointClosestToInf = i
                    distToInf = d

        if pointClosestToInf == -1:
            return compute_incenter_of_triangle(
                [ projectivePoint.as_ideal_point()
                  for projectivePoint in projectivePoints ])
        
        zInv = projectivePoints[pointClosestToInf].z
        CIF = zInv.parent()
        gl_matrix = matrix(CIF, [[ 1, 0], [-zInv, 1]])
        sl_matrix = CIF(sage.all.I) * gl_matrix
        inv_sl_matrix = _adjoint2(sl_matrix)
        
        transformedIdealPoints = [
            p.translate(gl_matrix).as_ideal_point()
            for i, p in enumerate(projectivePoints)
            if i != pointClosestToInf ]
        
        transformedInCenter = (
            _compute_incenter_of_triangle_with_one_point_at_infinity(
                transformedIdealPoints))
                    
        return transformedInCenter.translate_PSL(inv_sl_matrix)
Example #12
0
    def fromComplexIntervalFieldAndIdealPoint(CIF, z):
        """
        Constructs a :class:`ProjectivePoint` from a complex interval or
        ``idealPoint.Infinity``::

            sage: from sage.all import CIF
            sage: from snappy.verify.upper_halfspace import ideal_point
            sage: z = CIF(1, 3)
            sage: ProjectivePoint.fromComplexIntervalFieldAndIdealPoint(CIF, z)
            ProjectivePoint(1 + 3*I)
            sage: ProjectivePoint.fromComplexIntervalFieldAndIdealPoint(CIF, ideal_point.Infinity)
            ProjectivePoint(0, inverted = True)

        """

        if z == Infinity:
            return ProjectivePoint(CIF(0), inverted = True)
        return ProjectivePoint(z)
    def test_plane_plane(self):
        from sage.all import RealIntervalField, ComplexIntervalField
        CIF = ComplexIntervalField(120)
        RIF = RealIntervalField(120)

        pts = [[
            ProjectivePoint(CIF(1)),
            ProjectivePoint(CIF(3)),
            ProjectivePoint(CIF(2, 1))
        ],
               [
                   ProjectivePoint(CIF(-1)),
                   ProjectivePoint(CIF(-3)),
                   ProjectivePoint(CIF(-2, 1))
               ]]

        planes = [
            PlaneReflection.from_three_projective_points(*pt) for pt in pts
        ]

        p = PlanePlaneDistanceEngine(*planes)
        e = p.endpoints()
        if not abs(p.dist() - e[0].dist(e[1])) < 1e-20:
            raise Exception("Distance incorrect %r %r" %
                            (p.dist(), e[0].dist(e[1])))

        e_baseline = [
            FinitePoint(CIF(1.5),
                        RIF(0.75).sqrt()),
            FinitePoint(CIF(-1.5),
                        RIF(0.75).sqrt())
        ]

        for e0, e_baseline0 in zip(e, e_baseline):
            if not e0.dist(e_baseline0) < 1e-15:
                raise Exception("%s %s" % (e0, e_baseline0))
    def my_example(self):
        from sage.all import CIF, RIF
        finiteTriangle = FiniteTriangle([
            FinitePoint(CIF(0), RIF(2)),
            FinitePoint(CIF(0.5), RIF(3)),
            FinitePoint(CIF(-1), RIF(2.5))
        ])
        idealTriangle = IdealTriangle([
            ProjectivePoint(CIF(0, 1)),
            ProjectivePoint(CIF(1, 0)),
            ProjectivePoint(CIF(-1, 0))
        ])

        #print finiteTriangle.reflections[2][0]
        #print idealTriangle.reflections[1][0]

        e = FiniteIdealTriangleDistanceEngine(finiteTriangle, idealTriangle)
        d = e.compute_lowerbound()

        if d < 0.0001:
            raise Exception()
Example #15
0
    def test_matrix_taking_pts(self):
        
        from sage.all import CIF

        tri = [ ProjectivePoint(CIF(0)),
                ProjectivePoint(CIF(1)),
                ProjectivePoint(CIF(0), True) ]

        zs = [ CIF(1.2, 3.2), CIF(4.2, 2.2), CIF(-1.1, 3.5) ]

        import itertools

        for invs in itertools.product(*3*[[False, True]]):
            pts = [ ProjectivePoint(z, inverted = inv)
                    for inv, z in zip(invs, zs) ]
            
            m = ProjectivePoint.matrix_taking_0_1_inf_to_given_points(*pts)
            
            for t, pt in zip(tri, pts):
                if not t.translate(m).is_close_to(pt):
                    raise Exception("Points not matching")
Example #16
0
 def matrix2(self):
     from sage.all import RIF, CIF, matrix
     return matrix([[CIF(RIF(0.3), RIF(-1.4)),
                     CIF(RIF(3.6), RIF(6.3))],
                    [CIF(RIF(-0.3), RIF(1.1)),
                     CIF(1)]])
Example #17
0
 def matrix1(self):
     from sage.all import RIF, CIF, matrix
     return matrix([[CIF(RIF(1.3), RIF(-0.4)),
                     CIF(RIF(5.6), RIF(2.3))],
                    [CIF(RIF(-0.3), RIF(0.1)),
                     CIF(1)]])
Example #18
0
    def test_incenter(self):
        from snappy.snap.t3mlite import Perm4
        from sage.all import RIF, CIF, matrix
        
        epsilon = 1e-12
        bigEpsilon = 1e-6

        z0 = ProjectivePoint(CIF(0), inverted = True)
        z1 = ProjectivePoint(CIF(0))
        z2 = ProjectivePoint(CIF(1))
        
        for z in [CIF(0,1), CIF(0.5, 0.5), CIF(1.2, 1.3)]:
            z3_1 = ProjectivePoint(z)
            z3_2 = ProjectivePoint(z.conjugate())

            r1, p1 = ProjectivePoint.compute_inradius_and_incenter([z0, z1, z2, z3_1])
            r2, p2 = ProjectivePoint.compute_inradius_and_incenter([z0, z1, z2, z3_2])

            if not abs(r1 - r2) < epsilon:
                raise Exception("Different radii %r %r" % (r1, r2))

            if not abs(p1.t - p2.t) < epsilon:
                raise Exception("Different heights")

            if not abs(p1.z - p2.z.conjugate()) < epsilon:
                raise Exception("Not conjugate")

            if not abs(p1.dist(p2) - 2 * r1) < epsilon:
                raise Exception("Wrong radius")

        z3 = ProjectivePoint(CIF(1.2, 1.3))

        r1, p1 = ProjectivePoint.compute_inradius_and_incenter([z0, z1, z2, z3])
        for p in Perm4.S4():
            r2, p2 = ProjectivePoint.compute_inradius_and_incenter(
                self.perm4_act(p,[z0, z1, z2, z3]))
            
            if not abs(r1 - r2) < epsilon:
                raise Exception("Different radii %r %r" % (r1, r2))

            if not p1.dist(p2) < bigEpsilon:
                raise Exception("Different incenter %r %r %r" % (p1.dist(p2), p1, p2))

        m1 = self.matrix1()
        m2 = self.matrix2()

        for m in [m1, m2, m1 * m2, m1 * m1 * m2]:
            r2, p2 = ProjectivePoint.compute_inradius_and_incenter(
                [ z.translate(m) for z in [z0, z1, z2, z3]])

            if not abs(r1 - r2) < epsilon:
                raise Exception("Different radii %r %r" % (r1, r2))

            if not p1.translate_PGL(m).dist(p2) < bigEpsilon:
                raise Exception("Different incenter %r %r %r" % (p1.translate_PGL(m).dist(p2), p1.translate_PGL(m), p2))
            
        z_values = [ CIF(1.1, 1),
                     CIF(0.2, 1.3),
                     CIF(0.4, -0.3),
                     CIF(-0.1, 0.8) ]

        r1, p1 = ProjectivePoint.compute_inradius_and_incenter(
            [ ProjectivePoint(z_value) for z_value in z_values ])

        import itertools
        
        for invs in itertools.product(*4*[[False, True]]):
            zs = [ ProjectivePoint(1 / z_value if inv else z_value,
                                inverted = inv)
                   for inv, z_value in zip(invs, z_values) ]
            r2, p2 = ProjectivePoint.compute_inradius_and_incenter(zs)

            if not abs(r1 - r2) < epsilon:
                raise Exception("Different radii %r %r" % (r1, r2))

            if not p1.dist(p2) < bigEpsilon:
                raise Exception("Different incenter %r %r %r" % (p1.dist(p2), p2))