def test_hyper_as_trig():
from sympy.simplify.fu import _osborne, _osbornei
eq = sinh(x)**2 + cosh(x)**2
t, f = hyper_as_trig(eq)
assert f(fu(t)) == cosh(2 * x)
e, f = hyper_as_trig(tanh(x + y))
assert f(TR12(e)) == (tanh(x) + tanh(y)) / (tanh(x) * tanh(y) + 1)
d = Dummy()
assert _osborne(sinh(x), d) == I * sin(x * d)
assert _osborne(tanh(x), d) == I * tan(x * d)
assert _osborne(coth(x), d) == cot(x * d) / I
assert _osborne(cosh(x), d) == cos(x * d)
assert _osborne(sech(x), d) == sec(x * d)
assert _osborne(csch(x), d) == csc(x * d) / I
for func in (sinh, cosh, tanh, coth, sech, csch):
h = func(pi)
assert _osbornei(_osborne(h, d), d) == h
# /!\ the _osborne functions are not meant to work
# in the o(i(trig, d), d) direction so we just check
# that they work as they are supposed to work
assert _osbornei(cos(x * y + z), y) == cosh(x + z * I)
assert _osbornei(sin(x * y + z), y) == sinh(x + z * I) / I
assert _osbornei(tan(x * y + z), y) == tanh(x + z * I) / I
assert _osbornei(cot(x * y + z), y) == coth(x + z * I) * I
assert _osbornei(sec(x * y + z), y) == sech(x + z * I)
assert _osbornei(csc(x * y + z), y) == csch(x + z * I) * I
def test_simplifications():
x = Symbol('x')
assert sinh(asinh(x)) == x
assert sinh(acosh(x)) == sqrt(x - 1) * sqrt(x + 1)
assert sinh(atanh(x)) == x / sqrt(1 - x**2)
assert sinh(acoth(x)) == 1 / (sqrt(x - 1) * sqrt(x + 1))
assert cosh(asinh(x)) == sqrt(1 + x**2)
assert cosh(acosh(x)) == x
assert cosh(atanh(x)) == 1 / sqrt(1 - x**2)
assert cosh(acoth(x)) == x / (sqrt(x - 1) * sqrt(x + 1))
assert tanh(asinh(x)) == x / sqrt(1 + x**2)
assert tanh(acosh(x)) == sqrt(x - 1) * sqrt(x + 1) / x
assert tanh(atanh(x)) == x
assert tanh(acoth(x)) == 1 / x
assert coth(asinh(x)) == sqrt(1 + x**2) / x
assert coth(acosh(x)) == x / (sqrt(x - 1) * sqrt(x + 1))
assert coth(atanh(x)) == 1 / x
assert coth(acoth(x)) == x
assert csch(asinh(x)) == 1 / x
assert csch(acosh(x)) == 1 / (sqrt(x - 1) * sqrt(x + 1))
assert csch(atanh(x)) == sqrt(1 - x**2) / x
assert csch(acoth(x)) == sqrt(x - 1) * sqrt(x + 1)
assert sech(asinh(x)) == 1 / sqrt(1 + x**2)
assert sech(acosh(x)) == 1 / x
assert sech(atanh(x)) == sqrt(1 - x**2)
assert sech(acoth(x)) == sqrt(x - 1) * sqrt(x + 1) / x
def test_sech_rewrite():
x = Symbol('x')
assert sech(x).rewrite(exp) == 1 / (exp(x)/2 + exp(-x)/2) \
== sech(x).rewrite('tractable')
assert sech(x).rewrite(sinh) == I / sinh(x + I * pi / 2)
tanh_half = tanh(S.Half * x)**2
assert sech(x).rewrite(tanh) == (1 - tanh_half) / (1 + tanh_half)
coth_half = coth(S.Half * x)**2
assert sech(x).rewrite(coth) == (coth_half - 1) / (coth_half + 1)
def test_derivs():
x = Symbol('x')
assert coth(x).diff(x) == -sinh(x)**(-2)
assert sinh(x).diff(x) == cosh(x)
assert cosh(x).diff(x) == sinh(x)
assert tanh(x).diff(x) == -tanh(x)**2 + 1
assert csch(x).diff(x) == -coth(x) * csch(x)
assert sech(x).diff(x) == -tanh(x) * sech(x)
assert acoth(x).diff(x) == 1 / (-x**2 + 1)
assert asinh(x).diff(x) == 1 / sqrt(x**2 + 1)
assert acosh(x).diff(x) == 1 / sqrt(x**2 - 1)
assert atanh(x).diff(x) == 1 / (-x**2 + 1)
assert asech(x).diff(x) == -1 / (x * sqrt(1 - x**2))
assert acsch(x).diff(x) == -1 / (x**2 * sqrt(1 + x**(-2)))
def test_sign_assumptions():
p = Symbol('p', positive=True)
n = Symbol('n', negative=True)
assert sinh(n).is_negative is True
assert sinh(p).is_positive is True
assert cosh(n).is_positive is True
assert cosh(p).is_positive is True
assert tanh(n).is_negative is True
assert tanh(p).is_positive is True
assert csch(n).is_negative is True
assert csch(p).is_positive is True
assert sech(n).is_positive is True
assert sech(p).is_positive is True
assert coth(n).is_negative is True
assert coth(p).is_positive is True
def test_manualintegrate_trigonometry():
assert manualintegrate(sin(x), x) == -cos(x)
assert manualintegrate(tan(x), x) == -log(cos(x))
assert manualintegrate(sec(x), x) == log(sec(x) + tan(x))
assert manualintegrate(csc(x), x) == -log(csc(x) + cot(x))
assert manualintegrate(sin(x) * cos(x),
x) in [sin(x)**2 / 2, -cos(x)**2 / 2]
assert manualintegrate(-sec(x) * tan(x), x) == -sec(x)
assert manualintegrate(csc(x) * cot(x), x) == -csc(x)
assert manualintegrate(sec(x)**2, x) == tan(x)
assert manualintegrate(csc(x)**2, x) == -cot(x)
assert manualintegrate(x * sec(x**2), x) == log(tan(x**2) + sec(x**2)) / 2
assert manualintegrate(cos(x) * csc(sin(x)),
x) == -log(cot(sin(x)) + csc(sin(x)))
assert manualintegrate(cos(3 * x) * sec(x), x) == -x + sin(2 * x)
assert manualintegrate(sin(3*x)*sec(x), x) == \
-3*log(cos(x)) + 2*log(cos(x)**2) - 2*cos(x)**2
assert_is_integral_of(sinh(2 * x), cosh(2 * x) / 2)
assert_is_integral_of(x * cosh(x**2), sinh(x**2) / 2)
assert_is_integral_of(tanh(x), log(cosh(x)))
assert_is_integral_of(coth(x), log(sinh(x)))
f, F = sech(x), 2 * atan(tanh(x / 2))
assert manualintegrate(f, x) == F
assert (F.diff(x) -
f).rewrite(exp).simplify() == 0 # todo: equals returns None
f, F = csch(x), log(tanh(x / 2))
assert manualintegrate(f, x) == F
assert (F.diff(x) - f).rewrite(exp).simplify() == 0
def test_real_assumptions():
z = Symbol('z', real=False)
assert sinh(z).is_real is None
assert cosh(z).is_real is None
assert tanh(z).is_real is None
assert sech(z).is_real is None
assert csch(z).is_real is None
assert coth(z).is_real is None
def f(rv):
if not isinstance(rv, TrigonometricFunction):
return rv
const, x = rv.args[0].as_independent(d, as_Add=True)
a = x.xreplace({d: S.One}) + const * I
if isinstance(rv, sin):
return sinh(a) / I
elif isinstance(rv, cos):
return cosh(a)
elif isinstance(rv, tan):
return tanh(a) / I
elif isinstance(rv, cot):
return coth(a) * I
elif isinstance(rv, sec):
return sech(a)
elif isinstance(rv, csc):
return csch(a) * I
else:
raise NotImplementedError('unhandled %s' % rv.func)
def test_complex():
a, b = symbols('a,b', real=True)
z = a + b * I
for func in [sinh, cosh, tanh, coth, sech, csch]:
assert func(z).conjugate() == func(a - b * I)
for deep in [True, False]:
assert sinh(z).expand(
complex=True, deep=deep) == sinh(a) * cos(b) + I * cosh(a) * sin(b)
assert cosh(z).expand(
complex=True, deep=deep) == cosh(a) * cos(b) + I * sinh(a) * sin(b)
assert tanh(z).expand(
complex=True, deep=deep) == sinh(a) * cosh(a) / (cos(b)**2 + sinh(
a)**2) + I * sin(b) * cos(b) / (cos(b)**2 + sinh(a)**2)
assert coth(z).expand(
complex=True, deep=deep) == sinh(a) * cosh(a) / (sin(b)**2 + sinh(
a)**2) - I * sin(b) * cos(b) / (sin(b)**2 + sinh(a)**2)
assert csch(z).expand(complex=True, deep=deep) == cos(b) * sinh(a) / (sin(b)**2\
*cosh(a)**2 + cos(b)**2 * sinh(a)**2) - I*sin(b) * cosh(a) / (sin(b)**2\
*cosh(a)**2 + cos(b)**2 * sinh(a)**2)
assert sech(z).expand(complex=True, deep=deep) == cos(b) * cosh(a) / (sin(b)**2\
*sinh(a)**2 + cos(b)**2 * cosh(a)**2) - I*sin(b) * sinh(a) / (sin(b)**2\
*sinh(a)**2 + cos(b)**2 * cosh(a)**2)
def test_asech():
x = Symbol('x')
assert unchanged(asech, -x)
# values at fixed points
assert asech(1) == 0
assert asech(-1) == pi * I
assert asech(0) is oo
assert asech(2) == I * pi / 3
assert asech(-2) == 2 * I * pi / 3
assert asech(nan) is nan
# at infinites
assert asech(oo) == I * pi / 2
assert asech(-oo) == I * pi / 2
assert asech(zoo) == I * AccumBounds(-pi / 2, pi / 2)
assert asech(I) == log(1 + sqrt(2)) - I * pi / 2
assert asech(-I) == log(1 + sqrt(2)) + I * pi / 2
assert asech(sqrt(2) - sqrt(6)) == 11 * I * pi / 12
assert asech(sqrt(2 - 2 / sqrt(5))) == I * pi / 10
assert asech(-sqrt(2 - 2 / sqrt(5))) == 9 * I * pi / 10
assert asech(2 / sqrt(2 + sqrt(2))) == I * pi / 8
assert asech(-2 / sqrt(2 + sqrt(2))) == 7 * I * pi / 8
assert asech(sqrt(5) - 1) == I * pi / 5
assert asech(1 - sqrt(5)) == 4 * I * pi / 5
assert asech(-sqrt(2 * (2 + sqrt(2)))) == 5 * I * pi / 8
# properties
# asech(x) == acosh(1/x)
assert asech(sqrt(2)) == acosh(1 / sqrt(2))
assert asech(2 / sqrt(3)) == acosh(sqrt(3) / 2)
assert asech(2 / sqrt(2 + sqrt(2))) == acosh(sqrt(2 + sqrt(2)) / 2)
assert asech(2) == acosh(S.Half)
# asech(x) == I*acos(1/x)
# (Note: the exact formula is asech(x) == +/- I*acos(1/x))
assert asech(-sqrt(2)) == I * acos(-1 / sqrt(2))
assert asech(-2 / sqrt(3)) == I * acos(-sqrt(3) / 2)
assert asech(-S(2)) == I * acos(Rational(-1, 2))
assert asech(-2 / sqrt(2)) == I * acos(-sqrt(2) / 2)
# sech(asech(x)) / x == 1
assert expand_mul(sech(asech(sqrt(6) - sqrt(2))) /
(sqrt(6) - sqrt(2))) == 1
assert expand_mul(sech(asech(sqrt(6) + sqrt(2))) /
(sqrt(6) + sqrt(2))) == 1
assert (sech(asech(sqrt(2 + 2 / sqrt(5)))) /
(sqrt(2 + 2 / sqrt(5)))).simplify() == 1
assert (sech(asech(-sqrt(2 + 2 / sqrt(5)))) /
(-sqrt(2 + 2 / sqrt(5)))).simplify() == 1
assert (sech(asech(sqrt(2 * (2 + sqrt(2))))) /
(sqrt(2 * (2 + sqrt(2))))).simplify() == 1
assert expand_mul(sech(asech(1 + sqrt(5))) / (1 + sqrt(5))) == 1
assert expand_mul(sech(asech(-1 - sqrt(5))) / (-1 - sqrt(5))) == 1
assert expand_mul(sech(asech(-sqrt(6) - sqrt(2))) /
(-sqrt(6) - sqrt(2))) == 1
# numerical evaluation
assert str(asech(5 * I).n(6)) == '0.19869 - 1.5708*I'
assert str(asech(-5 * I).n(6)) == '0.19869 + 1.5708*I'
def test_sech_fdiff():
x = Symbol('x')
raises(ArgumentIndexError, lambda: sech(x).fdiff(2))
def test_sech_series():
x = Symbol('x')
assert sech(x).series(x, 0, 10) == \
1 - x**2/2 + 5*x**4/24 - 61*x**6/720 + 277*x**8/8064 + O(x**10)
def test_sech():
x, y = symbols('x, y')
k = Symbol('k', integer=True)
n = Symbol('n', positive=True)
assert sech(nan) is nan
assert sech(zoo) is nan
assert sech(oo) == 0
assert sech(-oo) == 0
assert sech(0) == 1
assert sech(-1) == sech(1)
assert sech(-x) == sech(x)
assert sech(pi * I) == sec(pi)
assert sech(-pi * I) == sec(pi)
assert sech(-2**1024 * E) == sech(2**1024 * E)
assert sech(pi * I / 2) is zoo
assert sech(-pi * I / 2) is zoo
assert sech((-3 * 10**73 + 1) * pi * I / 2) is zoo
assert sech((7 * 10**103 + 1) * pi * I / 2) is zoo
assert sech(pi * I) == -1
assert sech(-pi * I) == -1
assert sech(5 * pi * I) == -1
assert sech(8 * pi * I) == 1
assert sech(pi * I / 3) == 2
assert sech(pi * I * Rational(-2, 3)) == -2
assert sech(pi * I / 4) == sqrt(2)
assert sech(-pi * I / 4) == sqrt(2)
assert sech(pi * I * Rational(5, 4)) == -sqrt(2)
assert sech(pi * I * Rational(-5, 4)) == -sqrt(2)
assert sech(pi * I / 6) == 2 / sqrt(3)
assert sech(-pi * I / 6) == 2 / sqrt(3)
assert sech(pi * I * Rational(7, 6)) == -2 / sqrt(3)
assert sech(pi * I * Rational(-5, 6)) == -2 / sqrt(3)
assert sech(pi * I / 105) == 1 / cos(pi / 105)
assert sech(-pi * I / 105) == 1 / cos(pi / 105)
assert sech(x * I) == 1 / cos(x)
assert sech(k * pi * I) == 1 / cos(k * pi)
assert sech(17 * k * pi * I) == 1 / cos(17 * k * pi)
assert sech(n).is_real is True
assert expand_trig(sech(x +
y)) == 1 / (cosh(x) * cosh(y) + sinh(x) * sinh(y))
def test_issue_11254a():
assert not integrate(sech(x), (x, 0, 1)).has(Integral)