def test_GeometricDistribution():
p = S.One / 5
d = GeometricDistribution(p)
t = S('t')
assert d.expectation(x, x) == 1/p
assert d.expectation(x**2, x) - d.expectation(x, x)**2 == (1-p)/p**2
assert abs(d.cdf(20000).evalf() - 1) < .001
def test_GeometricDistribution():
p = S.One / 5
d = GeometricDistribution(p)
assert d.expectation(x, x) == 1 / p
assert d.expectation(x**2, x) - d.expectation(x, x)**2 == (1 - p) / p**2
assert abs(d.cdf(20000).evalf() - 1) < .001
assert d.characteristic_function(0).doit() == 1
def test_GeometricDistribution():
p = S.One / 5
d = GeometricDistribution(p)
assert d.expectation(x, x) == 1/p
assert d.expectation(x**2, x) - d.expectation(x, x)**2 == (1-p)/p**2
assert abs(d.cdf(20000).evalf() - 1) < .001
assert d.characteristic_function(0).doit() == 1
def test_GeometricDistribution():
p = S.One / 5
d = GeometricDistribution(p)
t = S('t')
assert d.expectation(x, x) == 1 / p
assert d.expectation(x**2, x) - d.expectation(x, x)**2 == (1 - p) / p**2
assert abs(d.cdf(20000).evalf() - 1) < .001
def test_GeometricDistribution():
p = S.One / 5
d = GeometricDistribution(p)
assert d.expectation(x, x) == 1/p
assert d.expectation(x**2, x) - d.expectation(x, x)**2 == (1-p)/p**2
assert abs(d.cdf(20000).evalf() - 1) < .001
assert abs(d.cdf(20000.8).evalf() - 1) < .001
G = Geometric('G', p=S(1)/4)
assert cdf(G)(S(7)/2) == P(G <= S(7)/2)
X = Geometric('X', Rational(1, 5))
Y = Geometric('Y', Rational(3, 10))
assert coskewness(X, X + Y, X + 2*Y).simplify() == sqrt(230)*Rational(81, 1150)
