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Mini Shell
Mini Shell
from sympy.core import Rational, S
from sympy.simplify import simplify, trigsimp
from sympy import pi, sqrt, symbols, ImmutableMatrix as Matrix, \
sin, cos, Function, Integral, Derivative, diff
from sympy.vector.vector import Vector, BaseVector, VectorAdd, \
VectorMul, VectorZero
from sympy.vector.coordsysrect import CoordSys3D
from sympy.vector.vector import Cross, Dot, cross
from sympy.testing.pytest import raises
C = CoordSys3D('C')
i, j, k = C.base_vectors()
a, b, c = symbols('a b c')
def test_cross():
v1 = C.x * i + C.z * C.z * j
v2 = C.x * i + C.y * j + C.z * k
assert Cross(v1, v2) == Cross(C.x*C.i + C.z**2*C.j, C.x*C.i + C.y*C.j + C.z*C.k)
assert Cross(v1, v2).doit() == C.z**3*C.i + (-C.x*C.z)*C.j + (C.x*C.y - C.x*C.z**2)*C.k
assert cross(v1, v2) == C.z**3*C.i + (-C.x*C.z)*C.j + (C.x*C.y - C.x*C.z**2)*C.k
assert Cross(v1, v2) == -Cross(v2, v1)
assert Cross(v1, v2) + Cross(v2, v1) == Vector.zero
def test_dot():
v1 = C.x * i + C.z * C.z * j
v2 = C.x * i + C.y * j + C.z * k
assert Dot(v1, v2) == Dot(C.x*C.i + C.z**2*C.j, C.x*C.i + C.y*C.j + C.z*C.k)
assert Dot(v1, v2).doit() == C.x**2 + C.y*C.z**2
assert Dot(v1, v2).doit() == C.x**2 + C.y*C.z**2
assert Dot(v1, v2) == Dot(v2, v1)
def test_vector_sympy():
"""
Test whether the Vector framework confirms to the hashing
and equality testing properties of SymPy.
"""
v1 = 3*j
assert v1 == j*3
assert v1.components == {j: 3}
v2 = 3*i + 4*j + 5*k
v3 = 2*i + 4*j + i + 4*k + k
assert v3 == v2
assert v3.__hash__() == v2.__hash__()
def test_vector():
assert isinstance(i, BaseVector)
assert i != j
assert j != k
assert k != i
assert i - i == Vector.zero
assert i + Vector.zero == i
assert i - Vector.zero == i
assert Vector.zero != 0
assert -Vector.zero == Vector.zero
v1 = a*i + b*j + c*k
v2 = a**2*i + b**2*j + c**2*k
v3 = v1 + v2
v4 = 2 * v1
v5 = a * i
assert isinstance(v1, VectorAdd)
assert v1 - v1 == Vector.zero
assert v1 + Vector.zero == v1
assert v1.dot(i) == a
assert v1.dot(j) == b
assert v1.dot(k) == c
assert i.dot(v2) == a**2
assert j.dot(v2) == b**2
assert k.dot(v2) == c**2
assert v3.dot(i) == a**2 + a
assert v3.dot(j) == b**2 + b
assert v3.dot(k) == c**2 + c
assert v1 + v2 == v2 + v1
assert v1 - v2 == -1 * (v2 - v1)
assert a * v1 == v1 * a
assert isinstance(v5, VectorMul)
assert v5.base_vector == i
assert v5.measure_number == a
assert isinstance(v4, Vector)
assert isinstance(v4, VectorAdd)
assert isinstance(v4, Vector)
assert isinstance(Vector.zero, VectorZero)
assert isinstance(Vector.zero, Vector)
assert isinstance(v1 * 0, VectorZero)
assert v1.to_matrix(C) == Matrix([[a], [b], [c]])
assert i.components == {i: 1}
assert v5.components == {i: a}
assert v1.components == {i: a, j: b, k: c}
assert VectorAdd(v1, Vector.zero) == v1
assert VectorMul(a, v1) == v1*a
assert VectorMul(1, i) == i
assert VectorAdd(v1, Vector.zero) == v1
assert VectorMul(0, Vector.zero) == Vector.zero
raises(TypeError, lambda: v1.outer(1))
raises(TypeError, lambda: v1.dot(1))
def test_vector_magnitude_normalize():
assert Vector.zero.magnitude() == 0
assert Vector.zero.normalize() == Vector.zero
assert i.magnitude() == 1
assert j.magnitude() == 1
assert k.magnitude() == 1
assert i.normalize() == i
assert j.normalize() == j
assert k.normalize() == k
v1 = a * i
assert v1.normalize() == (a/sqrt(a**2))*i
assert v1.magnitude() == sqrt(a**2)
v2 = a*i + b*j + c*k
assert v2.magnitude() == sqrt(a**2 + b**2 + c**2)
assert v2.normalize() == v2 / v2.magnitude()
v3 = i + j
assert v3.normalize() == (sqrt(2)/2)*C.i + (sqrt(2)/2)*C.j
def test_vector_simplify():
A, s, k, m = symbols('A, s, k, m')
test1 = (1 / a + 1 / b) * i
assert (test1 & i) != (a + b) / (a * b)
test1 = simplify(test1)
assert (test1 & i) == (a + b) / (a * b)
assert test1.simplify() == simplify(test1)
test2 = (A**2 * s**4 / (4 * pi * k * m**3)) * i
test2 = simplify(test2)
assert (test2 & i) == (A**2 * s**4 / (4 * pi * k * m**3))
test3 = ((4 + 4 * a - 2 * (2 + 2 * a)) / (2 + 2 * a)) * i
test3 = simplify(test3)
assert (test3 & i) == 0
test4 = ((-4 * a * b**2 - 2 * b**3 - 2 * a**2 * b) / (a + b)**2) * i
test4 = simplify(test4)
assert (test4 & i) == -2 * b
v = (sin(a)+cos(a))**2*i - j
assert trigsimp(v) == (2*sin(a + pi/4)**2)*i + (-1)*j
assert trigsimp(v) == v.trigsimp()
assert simplify(Vector.zero) == Vector.zero
def test_vector_dot():
assert i.dot(Vector.zero) == 0
assert Vector.zero.dot(i) == 0
assert i & Vector.zero == 0
assert i.dot(i) == 1
assert i.dot(j) == 0
assert i.dot(k) == 0
assert i & i == 1
assert i & j == 0
assert i & k == 0
assert j.dot(i) == 0
assert j.dot(j) == 1
assert j.dot(k) == 0
assert j & i == 0
assert j & j == 1
assert j & k == 0
assert k.dot(i) == 0
assert k.dot(j) == 0
assert k.dot(k) == 1
assert k & i == 0
assert k & j == 0
assert k & k == 1
raises(TypeError, lambda: k.dot(1))
def test_vector_cross():
assert i.cross(Vector.zero) == Vector.zero
assert Vector.zero.cross(i) == Vector.zero
assert i.cross(i) == Vector.zero
assert i.cross(j) == k
assert i.cross(k) == -j
assert i ^ i == Vector.zero
assert i ^ j == k
assert i ^ k == -j
assert j.cross(i) == -k
assert j.cross(j) == Vector.zero
assert j.cross(k) == i
assert j ^ i == -k
assert j ^ j == Vector.zero
assert j ^ k == i
assert k.cross(i) == j
assert k.cross(j) == -i
assert k.cross(k) == Vector.zero
assert k ^ i == j
assert k ^ j == -i
assert k ^ k == Vector.zero
assert k.cross(1) == Cross(k, 1)
def test_projection():
v1 = i + j + k
v2 = 3*i + 4*j
v3 = 0*i + 0*j
assert v1.projection(v1) == i + j + k
assert v1.projection(v2) == Rational(7, 3)*C.i + Rational(7, 3)*C.j + Rational(7, 3)*C.k
assert v1.projection(v1, scalar=True) == S.One
assert v1.projection(v2, scalar=True) == Rational(7, 3)
assert v3.projection(v1) == Vector.zero
assert v3.projection(v1, scalar=True) == S.Zero
def test_vector_diff_integrate():
f = Function('f')
v = f(a)*C.i + a**2*C.j - C.k
assert Derivative(v, a) == Derivative((f(a))*C.i +
a**2*C.j + (-1)*C.k, a)
assert (diff(v, a) == v.diff(a) == Derivative(v, a).doit() ==
(Derivative(f(a), a))*C.i + 2*a*C.j)
assert (Integral(v, a) == (Integral(f(a), a))*C.i +
(Integral(a**2, a))*C.j + (Integral(-1, a))*C.k)
def test_vector_args():
raises(ValueError, lambda: BaseVector(3, C))
raises(TypeError, lambda: BaseVector(0, Vector.zero))
Zerion Mini Shell 1.0