Пример #1
0
def test_extract_plane_and_line():
    """
    Show that conformal trivector encodes planes and lines. See D&L section
    10.4.2
    """
    metric = '# # # 0 0,'+ \
             '# # # 0 0,'+ \
             '# # # 0 0,'+ \
             '0 0 0 0 2,'+ \
             '0 0 0 2 0'

    MV.setup('p1 p2 p3 n nbar',metric,debug=0)
    MV.set_str_format(1)

    ZERO_MV = MV()

    P1 = F(p1)
    P2 = F(p2)
    P3 = F(p3)

    #Line through p1 and p2
    L = P1^P2^n
    delta = (L|n)|nbar
    delta_test = 2*p1-2*p2
    diff = delta-delta_test
    diff.compact()
    assert diff == ZERO_MV

    #Plane through p1, p2, and p3
    C = P1^P2^P3
    delta = ((C^n)|n)|nbar
    delta_test = 2*(p1^p2)-2*(p1^p3)+2*(p2^p3)
    diff = delta-delta_test
    diff.compact()
    assert diff == ZERO_MV
Пример #2
0
def test_vector_extraction():
    """
    Show that conformal bivector encodes two points. See D&L Section 10.4.1
    """
    metric = ' 0 -1 #,'+ \
             '-1  0 #,'+ \
             ' #  # #,'

    MV.setup('P1 P2 a',metric)
    """
    P1 and P2 are null vectors and hence encode points in conformal space.
    Show that P1 and P2 can be extracted from the bivector B = P1^P2. a is a
    third vector in the conformal space with a.B not 0.
    """
    ZERO_MV = MV()
    B = P1^P2
    Bsq = B*B
    ap = a-(a^B)*B
    Ap = ap+ap*B
    Am = ap-ap*B
    Ap_test = (-2*P2dota)*P1
    Am_test = (-2*P1dota)*P2
    Ap.compact()
    Am.compact()
    Ap_test.compact()
    Am_test.compact()
    assert Ap == Ap_test
    assert Am == Am_test
    Ap2 = Ap*Ap
    Am2 = Am*Am
    Ap2.compact()
    Am2.compact()
    assert Ap2 == ZERO_MV
    assert Am2 == ZERO_MV
Пример #3
0
def test_extract_plane_and_line():
    """
    Show that conformal trivector encodes planes and lines. See D&L section
    10.4.2
    """
    metric = '# # # 0 0,'+ \
             '# # # 0 0,'+ \
             '# # # 0 0,'+ \
             '0 0 0 0 2,'+ \
             '0 0 0 2 0'

    MV.setup('p1 p2 p3 n nbar',metric,debug=0)
    MV.set_str_format(1)

    ZERO_MV = MV()

    P1 = F(p1)
    P2 = F(p2)
    P3 = F(p3)

    #Line through p1 and p2
    L = P1^P2^n
    delta = (L|n)|nbar
    delta_test = 2*p1-2*p2
    diff = delta-delta_test
    diff.compact()
    assert diff == ZERO_MV

    #Plane through p1, p2, and p3
    C = P1^P2^P3
    delta = ((C^n)|n)|nbar
    delta_test = 2*(p1^p2)-2*(p1^p3)+2*(p2^p3)
    diff = delta-delta_test
    diff.compact()
    assert diff == ZERO_MV
Пример #4
0
def test_metrics():
    """
    Test specific metrics (diagpq, arbitrary_metric, arbitrary_metric_conformal)
    """
    from sympy.galgebra.GA import diagpq, arbitrary_metric, arbitrary_metric_conformal
    metric = diagpq(3)
    p1, p2, p3 = MV.setup('p1 p2 p3', metric, debug=0)
    MV.set_str_format(1)
    x1, y1, z1 = sympy.symbols('x1 y1 z1')
    x2, y2, z2 = sympy.symbols('x2 y2 z2')
    v1 = x1*p1 + y1*p2 + z1*p3
    v2 = x2*p1 + y2*p2 + z2*p3
    prod1 = v1*v2
    prod2 = (v1|v2) + (v1^v2)
    diff = prod1 - prod2
    diff.compact()
    assert diff == ZERO
    metric = arbitrary_metric(3)
    p1, p2, p3 = MV.setup('p1 p2 p3', metric, debug=0)
    v1 = x1*p1 + y1*p2 + z1*p3
    v2 = x2*p1 + y2*p2 + z2*p3
    prod1 = v1*v2
    prod2 = (v1|v2) + (v1^v2)
    diff = prod1 - prod2
    diff.compact()
    assert diff == ZERO
    metric = arbitrary_metric_conformal(3)
    p1, p2, p3 = MV.setup('p1 p2 p3', metric, debug=0)
    v1 = x1*p1 + y1*p2 + z1*p3
    v2 = x2*p1 + y2*p2 + z2*p3
    prod1 = v1*v2
    prod2 = (v1|v2) + (v1^v2)
    diff = prod1 - prod2
    diff.compact()
    assert diff == ZERO
Пример #5
0
def test_vector_extraction():
    """
    Show that conformal bivector encodes two points. See D&L Section 10.4.1
    """
    metric = ' 0 -1 #,'+ \
             '-1  0 #,'+ \
             ' #  # #,'

    MV.setup('P1 P2 a',metric)
    """
    P1 and P2 are null vectors and hence encode points in conformal space.
    Show that P1 and P2 can be extracted from the bivector B = P1^P2. a is a
    third vector in the conformal space with a.B not 0.
    """
    ZERO_MV = MV()
    B = P1^P2
    Bsq = B*B
    ap = a-(a^B)*B
    Ap = ap+ap*B
    Am = ap-ap*B
    Ap_test = (-2*P2dota)*P1
    Am_test = (-2*P1dota)*P2
    Ap.compact()
    Am.compact()
    Ap_test.compact()
    Am_test.compact()
    assert Ap == Ap_test
    assert Am == Am_test
    Ap2 = Ap*Ap
    Am2 = Am*Am
    Ap2.compact()
    Am2.compact()
    assert Ap2 == ZERO_MV
    assert Am2 == ZERO_MV
Пример #6
0
def test_substitution():

    MV.setup("e_x e_y e_z", "1 0 0, 0 1 0, 0 0 1", offset=1)
    make_symbols("x y z")

    X = x * e_x + y * e_y + z * e_z
    Y = X.subs([(x, 2), (y, 3), (z, 4)])
    assert Y == 2 * e_x + 3 * e_y + 4 * e_z
Пример #7
0
def test_substitution():

    MV.setup('e_x e_y e_z','1 0 0, 0 1 0, 0 0 1',offset=1)
    make_symbols('x y z')

    X = x*e_x+y*e_y+z*e_z
    Y = X.subs([(x,2),(y,3),(z,4)])
    assert Y == 2*e_x+3*e_y+4*e_z
Пример #8
0
def test_substitution():

    MV.setup('e_x e_y e_z','1 0 0, 0 1 0, 0 0 1',offset=1)
    make_symbols('x y z')

    X = x*e_x+y*e_y+z*e_z
    Y = X.subs([(x,2),(y,3),(z,4)])
    assert Y == 2*e_x+3*e_y+4*e_z
Пример #9
0
def test_derivative():
    coords = make_symbols("x y z")
    MV.setup("e", "1 0 0, 0 1 0, 0 0 1", coords=coords)
    X = x * e_x + y * e_y + z * e_z
    a = MV("a", "vector")

    assert ((X | a).grad()) == a
    assert ((X * X).grad()) == 2 * X
    assert (X * X * X).grad() == 5 * X * X
    assert X.grad_int() == 3
Пример #10
0
def test_str():
    MV.setup('e_1 e_2 e_3','1 0 0, 0 1 0, 0 0 1')

    X = MV('x')
    assert str(X) == 'x+x__0*e_1+x__1*e_2+x__2*e_3+x__01*e_1e_2+x__02*e_1e_3+x__12*e_2e_3+x__012*e_1e_2e_3'
    Y = MV('y','spinor')
    assert str(Y) == 'y+y__01*e_1e_2+y__02*e_1e_3+y__12*e_2e_3'
    Z = X+Y
    assert str(Z) == 'x+y+x__0*e_1+x__1*e_2+x__2*e_3+(x__01+y__01)*e_1e_2+(x__02+y__02)*e_1e_3+(x__12+y__12)*e_2e_3+x__012*e_1e_2e_3'
    assert str(e_1|e_1) == '1'
Пример #11
0
def test_derivative():
    coords = make_symbols('x y z')
    MV.setup('e','1 0 0, 0 1 0, 0 0 1',coords=coords)
    X = x*e_x+y*e_y+z*e_z
    a = MV('a','vector')

    assert ((X|a).grad()) == a
    assert ((X*X).grad()) == 2*X
    assert (X*X*X).grad() == 5*X*X
    assert X.grad_int() == 3
Пример #12
0
def test_str():
    MV.setup('e_1 e_2 e_3','1 0 0, 0 1 0, 0 0 1')

    X = MV('x')
    assert str(X) == 'x+x__0*e_1+x__1*e_2+x__2*e_3+x__01*e_1e_2+x__02*e_1e_3+x__12*e_2e_3+x__012*e_1e_2e_3'
    Y = MV('y','spinor')
    assert str(Y) == 'y+y__01*e_1e_2+y__02*e_1e_3+y__12*e_2e_3'
    Z = X+Y
    assert str(Z) == 'x+y+x__0*e_1+x__1*e_2+x__2*e_3+(x__01+y__01)*e_1e_2+(x__02+y__02)*e_1e_3+(x__12+y__12)*e_2e_3+x__012*e_1e_2e_3'
    assert str(e_1|e_1) == '1'
Пример #13
0
def test_derivative():
    coords = make_symbols('x y z')
    MV.setup('e','1 0 0, 0 1 0, 0 0 1',coords=coords)
    X = x*e_x+y*e_y+z*e_z
    a = MV('a','vector')

    assert ((X|a).grad()) == a
    assert ((X*X).grad()) == 2*X
    assert (X*X*X).grad() == 5*X*X
    assert X.grad_int() == 3
Пример #14
0
def test_geometry():
    """
    Test conformal geometric description of circles, lines, spheres, and planes.
    """
    metric = "1 0 0 0 0," + "0 1 0 0 0," + "0 0 1 0 0," + "0 0 0 0 2," + "0 0 0 2 0"

    MV.setup("e0 e1 e2 n nbar", metric, debug=0)
    e = n + nbar
    # conformal representation of points
    ZERO_MV = MV()

    A = make_vector(e0)  # point a = (1,0,0)  A = F(a)
    B = make_vector(e1)  # point b = (0,1,0)  B = F(b)
    C = make_vector(-1 * e0)  # point c = (-1,0,0) C = F(c)
    D = make_vector(e2)  # point d = (0,0,1)  D = F(d)
    X = make_vector("x", 3)

    Circle = A ^ B ^ C ^ X
    Line = A ^ B ^ n ^ X
    Sphere = A ^ B ^ C ^ D ^ X
    Plane = A ^ B ^ n ^ D ^ X

    # Circle through a, b, and c
    Circle_test = (
        -x2 * (e0 ^ e1 ^ e2 ^ n)
        + x2 * (e0 ^ e1 ^ e2 ^ nbar)
        + HALF * (-1 + x0 ** 2 + x1 ** 2 + x2 ** 2) * (e0 ^ e1 ^ n ^ nbar)
    )
    diff = Circle - Circle_test
    diff.compact()
    assert diff == ZERO_MV

    # Line through a and b
    Line_test = (
        -x2 * (e0 ^ e1 ^ e2 ^ n)
        + HALF * (-1 + x0 + x1) * (e0 ^ e1 ^ n ^ nbar)
        + (HALF * x2) * (e0 ^ e2 ^ n ^ nbar)
        + (-HALF * x2) * (e1 ^ e2 ^ n ^ nbar)
    )
    diff = Line - Line_test
    diff.compact()
    assert diff == ZERO_MV

    # Sphere through a, b, c, and d
    Sphere_test = HALF * (1 - x0 ** 2 - x1 ** 2 - x2 ** 2) * (e0 ^ e1 ^ e2 ^ n ^ nbar)
    diff = Sphere - Sphere_test
    diff.compact()
    assert diff == ZERO_MV

    # Plane through a, b, and d
    Plane_test = HALF * (1 - x0 - x1 - x2) * (e0 ^ e1 ^ e2 ^ n ^ nbar)
    diff = Plane - Plane_test
    diff.compact()
    assert diff == ZERO_MV
Пример #15
0
def test_rmul():
    """
    Test for communitive scalar multiplication.  Leftover from when sympy and
    numpy were not working together and __mul__ and __rmul__ would not give the
    same answer.
    """
    MV.setup('x y z')
    make_symbols('a b c')
    assert 5*x == x*5
    assert HALF*x == x*HALF
    assert a*x == x*a
Пример #16
0
def test_rmul():
    """
    Test for commutative scalar multiplication.  Leftover from when sympy and
    numpy were not working together and __mul__ and __rmul__ would not give the
    same answer.
    """
    MV.setup('x y z')
    make_symbols('a b c')
    assert 5*x == x*5
    assert HALF*x == x*HALF
    assert a*x == x*a
Пример #17
0
def test_geometry():
    """
    Test conformal geometric description of circles, lines, spheres, and planes.
    """
    metric = '1 0 0 0 0,'+ \
             '0 1 0 0 0,'+ \
             '0 0 1 0 0,'+ \
             '0 0 0 0 2,'+ \
             '0 0 0 2 0'

    MV.setup('e0 e1 e2 n nbar', metric, debug=0)
    e = n + nbar
    #conformal representation of points
    ZERO_MV = MV()

    A = make_vector(e0)  # point a = (1,0,0)  A = F(a)
    B = make_vector(e1)  # point b = (0,1,0)  B = F(b)
    C = make_vector(-1 * e0)  # point c = (-1,0,0) C = F(c)
    D = make_vector(e2)  # point d = (0,0,1)  D = F(d)
    X = make_vector('x', 3)

    Circle = A ^ B ^ C ^ X
    Line = A ^ B ^ n ^ X
    Sphere = A ^ B ^ C ^ D ^ X
    Plane = A ^ B ^ n ^ D ^ X

    #Circle through a, b, and c
    Circle_test = -x2 * (e0 ^ e1 ^ e2 ^ n) + x2 * (
        e0 ^ e1 ^ e2 ^ nbar) + HALF * (-1 + x0**2 + x1**2 +
                                       x2**2) * (e0 ^ e1 ^ n ^ nbar)
    diff = Circle - Circle_test
    diff.compact()
    assert diff == ZERO_MV

    #Line through a and b
    Line_test = -x2*(e0^e1^e2^n)+HALF*(-1+x0+x1)*(e0^e1^n^nbar)+(HALF*x2)*(e0^e2^n^nbar)+\
                (-HALF*x2)*(e1^e2^n^nbar)
    diff = Line - Line_test
    diff.compact()
    assert diff == ZERO_MV

    #Sphere through a, b, c, and d
    Sphere_test = HALF * (1 - x0**2 - x1**2 - x2**2) * (e0 ^ e1 ^ e2 ^ n
                                                        ^ nbar)
    diff = Sphere - Sphere_test
    diff.compact()
    assert diff == ZERO_MV

    #Plane through a, b, and d
    Plane_test = HALF * (1 - x0 - x1 - x2) * (e0 ^ e1 ^ e2 ^ n ^ nbar)
    diff = Plane - Plane_test
    diff.compact()
    assert diff == ZERO_MV
Пример #18
0
def test_reciprocal_frame():
    """
    Test of formula for general reciprocal frame of three vectors.
    Let three independent vectors be e1, e2, and e3. The reciprocal
    vectors E1, E2, and E3 obey the relations:

    e_i.E_j = delta_ij*(e1^e2^e3)**2
    """
    metric = '1 # #,'+ \
             '# 1 #,'+ \
             '# # 1,'

    MV.setup('e1 e2 e3',metric)
    E = e1^e2^e3
    Esq = (E*E)()
    Esq_inv = 1/Esq
    E1 = (e2^e3)*E
    E2 = (-1)*(e1^e3)*E
    E3 = (e1^e2)*E
    w = (E1|e2)
    w.collect(MV.g)
    w = w().expand()
    w = (E1|e3)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E2|e1)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E2|e3)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E3|e1)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E3|e2)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E1|e1)
    w = w().expand()
    Esq = Esq.expand()
    assert w/Esq == 1
    w = (E2|e2)
    w = w().expand()
    assert w/Esq == 1
    w = (E3|e3)
    w = w().expand()
    assert w/Esq == 1
Пример #19
0
def test_reciprocal_frame():
    """
    Test of fromula for general reciprocal frame of three vectors.
    Let three independent vectors be e1, e2, and e3. The reciprocal
    vectors E1, E2, and E3 obey the relations:

    e_i.E_j = delta_ij*(e1^e2^e3)**2
    """
    metric = '1 # #,'+ \
             '# 1 #,'+ \
             '# # 1,'

    MV.setup('e1 e2 e3',metric)
    E = e1^e2^e3
    Esq = (E*E)()
    Esq_inv = 1/Esq
    E1 = (e2^e3)*E
    E2 = (-1)*(e1^e3)*E
    E3 = (e1^e2)*E
    w = (E1|e2)
    w.collect(MV.g)
    w = w().expand()
    w = (E1|e3)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E2|e1)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E2|e3)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E3|e1)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E3|e2)
    w.collect(MV.g)
    w = w().expand()
    assert w == 0
    w = (E1|e1)
    w = w().expand()
    Esq = Esq.expand()
    assert w/Esq == 1
    w = (E2|e2)
    w = w().expand()
    assert w/Esq == 1
    w = (E3|e3)
    w = w().expand()
    assert w/Esq == 1
Пример #20
0
def test_str():
    MV.setup("e_1 e_2 e_3", "1 0 0, 0 1 0, 0 0 1")

    X = MV("x")
    assert str(X) == "x+x__0*e_1+x__1*e_2+x__2*e_3+x__01*e_1e_2+x__02*e_1e_3+x__12*e_2e_3+x__012*e_1e_2e_3"
    Y = MV("y", "spinor")
    assert str(Y) == "y+y__01*e_1e_2+y__02*e_1e_3+y__12*e_2e_3"
    Z = X + Y
    assert (
        str(Z)
        == "x+y+x__0*e_1+x__1*e_2+x__2*e_3+(x__01+y__01)*e_1e_2+(x__02+y__02)*e_1e_3+(x__12+y__12)*e_2e_3+x__012*e_1e_2e_3"
    )
    assert str(e_1 | e_1) == "1"
Пример #21
0
def test_contraction():
    """
    Test for inner product and left and right contraction
    """

    MV.setup('e_1 e_2 e_3','1 0 0, 0 1 0, 0 0 1',offset=1)

    assert ((e_1^e_3)|e_1) == -e_3
    assert ((e_1^e_3)>e_1) == -e_3
    assert (e_1|(e_1^e_3)) == e_3
    assert (e_1<(e_1^e_3)) == e_3
    assert ((e_1^e_3)<e_1) == 0
    assert (e_1>(e_1^e_3)) == 0
Пример #22
0
def test_contraction():
    """
    Test for inner product and left and right contraction
    """

    MV.setup('e_1 e_2 e_3','1 0 0, 0 1 0, 0 0 1',offset=1)

    assert ((e_1^e_3)|e_1) == -e_3
    assert ((e_1^e_3)>e_1) == -e_3
    assert (e_1|(e_1^e_3)) == e_3
    assert (e_1<(e_1^e_3)) == e_3
    assert ((e_1^e_3)<e_1) == 0
    assert (e_1>(e_1^e_3)) == 0
Пример #23
0
def test_constructor():
    """
    Test various multivector constructors
    """
    MV.setup("e_1 e_2 e_3", "[1,1,1]")
    make_symbols("x")
    assert str(S(1)) == "1"
    assert str(S(x)) == "x"
    assert str(MV("a", "scalar")) == "a"
    assert str(MV("a", "vector")) == "a__0*e_1+a__1*e_2+a__2*e_3"
    assert str(MV("a", "pseudo")) == "a*e_1e_2e_3"
    assert str(MV("a", "spinor")) == "a+a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3"
    assert str(MV("a")) == "a+a__0*e_1+a__1*e_2+a__2*e_3+a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3+a__012*e_1e_2e_3"
    assert str(MV([2, "a"], "grade")) == "a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3"
    assert str(MV("a", "grade2")) == "a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3"
Пример #24
0
def test_constructor():
    """
    Test various multivector constructors
    """
    MV.setup('e_1 e_2 e_3','[1,1,1]')
    make_symbols('x')
    assert str(S(1)) == '1'
    assert str(S(x)) == 'x'
    assert str(MV('a','scalar')) == 'a'
    assert str(MV('a','vector')) == 'a__0*e_1+a__1*e_2+a__2*e_3'
    assert str(MV('a','pseudo')) == 'a*e_1e_2e_3'
    assert str(MV('a','spinor')) == 'a+a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3'
    assert str(MV('a')) == 'a+a__0*e_1+a__1*e_2+a__2*e_3+a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3+a__012*e_1e_2e_3'
    assert str(MV([2,'a'],'grade')) == 'a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3'
    assert str(MV('a','grade2')) == 'a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3'
Пример #25
0
def test_constructor():
    """
    Test various multivector constructors
    """
    MV.setup('e_1 e_2 e_3','[1,1,1]')
    make_symbols('x')
    assert str(S(1)) == '1'
    assert str(S(x)) == 'x'
    assert str(MV('a','scalar')) == 'a'
    assert str(MV('a','vector')) == 'a__0*e_1+a__1*e_2+a__2*e_3'
    assert str(MV('a','pseudo')) == 'a*e_1e_2e_3'
    assert str(MV('a','spinor')) == 'a+a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3'
    assert str(MV('a')) == 'a+a__0*e_1+a__1*e_2+a__2*e_3+a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3+a__012*e_1e_2e_3'
    assert str(MV([2,'a'],'grade')) == 'a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3'
    assert str(MV('a','grade2')) == 'a__01*e_1e_2+a__02*e_1e_3+a__12*e_2e_3'
Пример #26
0
def test_geometry():
    """
    Test conformal geometric description of circles, lines, spheres, and planes.
    """
    metric = '1 0 0 0 0,' + \
             '0 1 0 0 0,' + \
             '0 0 1 0 0,' + \
             '0 0 0 0 2,' + \
             '0 0 0 2 0'

    e0, e1, e2, n, nbar = MV.setup('e0 e1 e2 n nbar', metric, debug=0)
    e = n + nbar
    #conformal representation of points

    A = F(e0, n, nbar)    # point a = (1,0,0)  A = F(a)
    B = F(e1, n, nbar)    # point b = (0,1,0)  B = F(b)
    C = F(-1*e0, n, nbar)  # point c = (-1,0,0) C = F(c)
    D = F(e2, n, nbar)    # point d = (0,0,1)  D = F(d)
    x0, x1, x2 = sympy.symbols('x0 x1 x2')
    X = F(MV([x0, x1, x2], 'vector'), n, nbar)

    Circle = A ^ B ^ C ^ X
    Line = A ^ B ^ n ^ X
    Sphere = A ^ B ^ C ^ D ^ X
    Plane = A ^ B ^ n ^ D ^ X

    #Circle through a, b, and c
    Circle_test = -x2*(e0 ^ e1 ^ e2 ^ n) + x2*(
        e0 ^ e1 ^ e2 ^ nbar) + HALF*(-1 + x0**2 + x1**2 + x2**2)*(e0 ^ e1 ^ n ^ nbar)
    diff = Circle - Circle_test
    diff.compact()
    assert diff == ZERO

    #Line through a and b
    Line_test = -x2*(e0 ^ e1 ^ e2 ^ n) + \
        HALF*(-1 + x0 + x1)*(e0 ^ e1 ^ n ^ nbar) + \
        (HALF*x2)*(e0 ^ e2 ^ n ^ nbar) + \
        (-HALF*x2)*(e1 ^ e2 ^ n ^ nbar)
    diff = Line - Line_test
    diff.compact()
    assert diff == ZERO

    #Sphere through a, b, c, and d
    Sphere_test = HALF*(1 - x0**2 - x1**2 - x2**2)*(e0 ^ e1 ^ e2 ^ n ^ nbar)
    diff = Sphere - Sphere_test
    diff.compact()
    assert diff == ZERO

    #Plane through a, b, and d
    Plane_test = HALF*(1 - x0 - x1 - x2)*(e0 ^ e1 ^ e2 ^ n ^ nbar)
    diff = Plane - Plane_test
    diff.compact()
    assert diff == ZERO
Пример #27
0
def test_geometry():
    """
    Test conformal geometric description of circles, lines, spheres, and planes.
    """
    metric = '1 0 0 0 0,'+ \
             '0 1 0 0 0,'+ \
             '0 0 1 0 0,'+ \
             '0 0 0 0 2,'+ \
             '0 0 0 2 0'

    e0, e1, e2, n, nbar = MV.setup('e0 e1 e2 n nbar', metric, debug=0)
    e = n + nbar
    #conformal representation of points

    A = F(e0, n, nbar)  # point a = (1,0,0)  A = F(a)
    B = F(e1, n, nbar)  # point b = (0,1,0)  B = F(b)
    C = F(-1 * e0, n, nbar)  # point c = (-1,0,0) C = F(c)
    D = F(e2, n, nbar)  # point d = (0,0,1)  D = F(d)
    x0, x1, x2 = sympy.symbols('x0 x1 x2')
    X = F(MV([x0, x1, x2], 'vector'), n, nbar)

    Circle = A ^ B ^ C ^ X
    Line = A ^ B ^ n ^ X
    Sphere = A ^ B ^ C ^ D ^ X
    Plane = A ^ B ^ n ^ D ^ X

    #Circle through a, b, and c
    Circle_test = -x2 * (e0 ^ e1 ^ e2 ^ n) + x2 * (
        e0 ^ e1 ^ e2 ^ nbar) + HALF * (-1 + x0**2 + x1**2 +
                                       x2**2) * (e0 ^ e1 ^ n ^ nbar)
    diff = Circle - Circle_test
    diff.compact()
    assert diff == ZERO

    #Line through a and b
    Line_test = -x2*(e0^e1^e2^n)+HALF*(-1+x0+x1)*(e0^e1^n^nbar)+(HALF*x2)*(e0^e2^n^nbar)+\
                (-HALF*x2)*(e1^e2^n^nbar)
    diff = Line - Line_test
    diff.compact()
    assert diff == ZERO

    #Sphere through a, b, c, and d
    Sphere_test = HALF * (1 - x0**2 - x1**2 - x2**2) * (e0 ^ e1 ^ e2 ^ n
                                                        ^ nbar)
    diff = Sphere - Sphere_test
    diff.compact()
    assert diff == ZERO

    #Plane through a, b, and d
    Plane_test = HALF * (1 - x0 - x1 - x2) * (e0 ^ e1 ^ e2 ^ n ^ nbar)
    diff = Plane - Plane_test
    diff.compact()
    assert diff == ZERO
Пример #28
0
    if type(a) == types.StringType:
        sym_str = ''
        for i in range(n):
            sym_str += a + str(i) + ' '
        sym_lst = make_symbols(sym_str)
        sym_lst.append(ZERO)
        sym_lst.append(ZERO)
        a = MV(sym_lst, 'vector')
    return (F(a))


if __name__ == '__main__':

    ti = time.time()

    MV.setup('a b c d e')
    MV.set_str_format(1)

    print 'e|(a^b) =', e | (a ^ b)
    print 'e|(a^b^c) =', e | (a ^ b ^ c)
    print 'a*(b^c)-b*(a^c)+c*(a^b) =', a * (b ^ c) - b * (a ^ c) + c * (a ^ b)
    print 'e|(a^b^c^d) =', e | (a ^ b ^ c ^ d)
    print -d * (a ^ b ^ c) + c * (a ^ b ^ d) - b * (a ^ c ^ d) + a * (b ^ c
                                                                      ^ d)

    print(a ^ b) | (c ^ d)

    # FIXME: currently broken
    """
    print 'Example: non-euclidian distance calculation'
Пример #29
0
def test_noneuclidian():
    """
    Test of complex geometric algebra manipulation to derive distance function
    for 2-D hyperbolic non-euclidian space.  See D&L Section 10.6.2
    """
    metric = '0 # #,'+ \
             '# 0 #,'+ \
             '# # 1,'
    MV.setup('X Y e',metric,debug=0)
    MV.set_str_format(1)
    L = X^Y^e
    B = L*e
    Bsq = (B*B)()
    BeBr =B*e*B.rev()
    (s,c,Binv,M,S,C,alpha) = sympy.symbols('s','c','Binv','M','S','C','alpha')
    Bhat = Binv*B # Normalize translation generator
    R = c+s*Bhat # Rotor R = exp(alpha*Bhat/2)
    Z = R*X*R.rev()
    Z.expand()
    Z.collect([Binv,s,c,XdotY])
    W = Z|Y
    W.expand()
    W.collect([s*Binv])
    M = 1/Bsq
    W.subs(Binv**2,M)
    W.simplify()
    Bmag = sympy.sqrt(XdotY**2-2*XdotY*Xdote*Ydote)
    W.collect([Binv*c*s,XdotY])
    W.subs(2*XdotY**2-4*XdotY*Xdote*Ydote,2/(Binv**2))
    W.subs(2*c*s,S)
    W.subs(c**2,(C+1)/2)
    W.subs(s**2,(C-1)/2)
    W.simplify()
    W.subs(1/Binv,Bmag)

    W = W().expand()
    #print '(R*X*R.rev()).Y =',W
    Wd = collect(W,[C,S],exact=True,evaluate=False)
    #print 'Wd =',Wd
    Wd_1 = Wd[ONE]
    Wd_C = Wd[C]
    Wd_S = Wd[S]
    #print '|B| =',Bmag
    Wd_1 = Wd_1.subs(Bmag,1/Binv)
    Wd_C = Wd_C.subs(Bmag,1/Binv)
    Wd_S = Wd_S.subs(Bmag,1/Binv)
    #print 'Wd[ONE] =',Wd_1
    #print 'Wd[C] =',Wd_C
    #print 'Wd[S] =',Wd_S
    lhs = Wd_1+Wd_C*C
    rhs = -Wd_S*S
    lhs = lhs**2
    rhs = rhs**2
    W = (lhs-rhs).expand()
    W = (W.subs(1/Binv**2,Bmag**2)).expand()
    #print 'W =',W
    W = (W.subs(S**2,C**2-1)).expand()
    W = collect(W,[C**2,C],evaluate=False)
    #print 'W =',W
    a = W[C**2]
    b = W[C]
    c = W[ONE]
    #print 'a =',a
    #print 'b =',b
    #print 'c =',c
    D = (b**2-4*a*c).expand()
    #print 'Setting to 0 and solving for C gives:'
    #print 'Descriminant D = b^2-4*a*c =',D
    C = (-b/(2*a)).expand()
    #print 'C = cosh(alpha) = -b/(2*a) =',C

    #cosh(alpha) = 1-X.Y/((X.e)(Y.e))
    #alpha is noneuclidian distance
    assert C == 1-XdotY/(Xdote*Ydote)
Пример #30
0
def test_metric():
    MV.setup("e_1 e_2 e_3", "[1,1,1]")
    assert str(MV.metric) == "[[1 0 0]\n [0 1 0]\n [0 0 1]]"
Пример #31
0
def test_metric():
    MV.setup('e_1 e_2 e_3','[1,1,1]')
    assert str(MV.metric) == '[[1 0 0]\n [0 1 0]\n [0 0 1]]'
Пример #32
0
def make_vector(a,n = 3):
        if type(a) == types.StringType:
                sym_str = ''
                for i in range(n):
                        sym_str += a+str(i)+' '
                sym_lst = make_symbols(sym_str)
                sym_lst.append(ZERO)
                sym_lst.append(ZERO)
                a = MV(sym_lst,'vector')
        return(F(a))

if __name__ == '__main__':

    ti = time.time()

    MV.setup('a b c d e')
    MV.set_str_format(1)

    print 'e|(a^b) =',e|(a^b)
    print 'e|(a^b^c) =',e|(a^b^c)
    print 'a*(b^c)-b*(a^c)+c*(a^b) =',a*(b^c)-b*(a^c)+c*(a^b)
    print 'e|(a^b^c^d) =',e|(a^b^c^d)
    print -d*(a^b^c)+c*(a^b^d)-b*(a^c^d)+a*(b^c^d)

    print (a^b)|(c^d)

    print 'Example: non-euclidian distance calculation'

    metric = '0 # #,# 0 #,# # 1'
    MV.setup('X Y e',metric)
    MV.set_str_format(1)
Пример #33
0
def test_metric():
    MV.setup('e_1 e_2 e_3', '[1,1,1]')
    assert str(MV.metric) == '[[1 0 0]\n [0 1 0]\n [0 0 1]]'