def test_cosh_expansion(): x, y = symbols('x,y') assert cosh(x + y).expand(trig=True) == cosh(x) * cosh(y) + sinh(x) * sinh(y) assert cosh(2 * x).expand(trig=True) == cosh(x)**2 + sinh(x)**2 assert cosh(3*x).expand(trig=True).expand() == \ 3*sinh(x)**2*cosh(x) + cosh(x)**3
def test_simplifications(): 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_ode_solutions(): # only a few examples here, the rest will be tested in the actual dsolve tests assert constant_renumber(constantsimp(C1*exp(2*x) + exp(x)*(C2 + C3), [C1, C2, C3]), 'C', 1, 3) == \ constant_renumber((C1*exp(x) + C2*exp(2*x)), 'C', 1, 2) assert constant_renumber( constantsimp(Eq(f(x), I*C1*sinh(x/3) + C2*cosh(x/3)), [C1, C2]), 'C', 1, 2) == constant_renumber(Eq(f(x), C1*sinh(x/3) + C2*cosh(x/3)), 'C', 1, 2) assert constant_renumber(constantsimp(Eq(f(x), acos((-C1)/cos(x))), [C1]), 'C', 1, 1) == \ Eq(f(x), acos(C1/cos(x))) assert constant_renumber( constantsimp(Eq(log(f(x)/C1) + 2*exp(x/f(x)), 0), [C1]), 'C', 1, 1) == Eq(log(C1*f(x)) + 2*exp(x/f(x)), 0) assert constant_renumber(constantsimp(Eq(log(x*sqrt(2)*sqrt(1/x)*sqrt(f(x)) / C1) + x**2/(2*f(x)**2), 0), [C1]), 'C', 1, 1) == \ Eq(log(C1*sqrt(x)*sqrt(f(x))) + x**2/(2*f(x)**2), 0) assert constant_renumber(constantsimp(Eq(-exp(-f(x)/x)*sin(f(x)/x)/2 + log(x/C1) - cos(f(x)/x)*exp(-f(x)/x)/2, 0), [C1]), 'C', 1, 1) == \ Eq(-exp(-f(x)/x)*sin(f(x)/x)/2 + log(C1*x) - cos(f(x)/x) * exp(-f(x)/x)/2, 0) u2 = Symbol('u2') _a = Symbol('_a') assert constant_renumber(constantsimp(Eq(-Integral(-1/(sqrt(1 - u2**2)*u2), (u2, _a, x/f(x))) + log(f(x)/C1), 0), [C1]), 'C', 1, 1) == \ Eq(-Integral(-1/(u2*sqrt(1 - u2**2)), (u2, _a, x/f(x))) + log(C1*f(x)), 0) assert [constantsimp(i, [C1]) for i in [Eq(f(x), sqrt(-C1*x + x**2)), Eq(f(x), -sqrt(-C1*x + x**2))]] == \ [Eq(f(x), sqrt(x*(C1 + x))), Eq(f(x), -sqrt(x*(C1 + x)))]
def test_sinh_series(): assert sinh(x).series(x, 0, 10) == \ x + x**3/6 + x**5/120 + x**7/5040 + x**9/362880 + O(x**10) assert sinh(x).taylor_term(1, x) == x assert sinh(x).taylor_term(3, x) == x**3 / 6 assert sinh(x).taylor_term(3, x, *(x, 0)) == sinh(x).taylor_term(3, x)
def test_sympyissue_6920(): e = [cos(x) + I*sin(x), cos(x) - I*sin(x), cosh(x) - sinh(x), cosh(x) + sinh(x)] ok = [exp(I*x), exp(-I*x), exp(-x), exp(x)] # wrap in f to show that the change happens wherever ei occurs f = Function('f') assert [simplify(f(ei)).args[0] for ei in e] == ok
def test_simplifications(): 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_tan_rewrite(): neg_exp, pos_exp = exp(-x*I), exp(x*I) assert tan(x).rewrite(exp) == I*(neg_exp - pos_exp)/(neg_exp + pos_exp) assert tan(x).rewrite(sin) == 2*sin(x)**2/sin(2*x) assert tan(x).rewrite(cos) == -cos(x + pi/2)/cos(x) assert tan(x).rewrite(cot) == 1/cot(x) assert (tan(sinh(x)).rewrite(exp).subs({x: 3}).evalf() == tan(x).rewrite(exp).subs({x: sinh(3)}).evalf()) assert (tan(cosh(x)).rewrite(exp).subs({x: 3}).evalf() == tan(x).rewrite(exp).subs({x: cosh(3)}).evalf()) assert (tan(tanh(x)).rewrite(exp).subs({x: 3}).evalf() == tan(x).rewrite(exp).subs({x: tanh(3)}).evalf()) assert (tan(coth(x)).rewrite(exp).subs({x: 3}).evalf() == tan(x).rewrite(exp).subs({x: coth(3)}).evalf()) assert (tan(sin(x)).rewrite(exp).subs({x: 3}).evalf() == tan(x).rewrite(exp).subs({x: sin(3)}).evalf()) assert (tan(cos(x)).rewrite(exp).subs({x: 3}).evalf() == tan(x).rewrite(exp).subs({x: cos(3)}).evalf()) assert (tan(tan(x)).rewrite(exp).subs({x: 3}).evalf() == tan(x).rewrite(exp).subs({x: tan(3)}).evalf()) assert (tan(cot(x)).rewrite(exp).subs({x: 3}).evalf() == tan(x).rewrite(exp).subs({x: cot(3)}).evalf()) assert tan(log(x)).rewrite(Pow) == I*(x**-I - x**I)/(x**-I + x**I) assert tan(x).rewrite(Pow) == tan(x) assert 0 == (cos(pi/34)*tan(pi/34) - sin(pi/34)).rewrite(sqrt) assert 0 == (cos(pi/17)*tan(pi/17) - sin(pi/17)).rewrite(sqrt) assert tan(pi/19).rewrite(sqrt) == tan(pi/19) assert tan(8*pi/19).rewrite(sqrt) == tan(8*pi/19)
def test_hyper_as_trig(): from diofant.simplify.fu import _osborne as o, _osbornei as i, TR12 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 o(sinh(x), d) == I*sin(x*d) assert o(tanh(x), d) == I*tan(x*d) assert o(coth(x), d) == cot(x*d)/I assert o(cosh(x), d) == cos(x*d) for func in (sinh, cosh, tanh, coth): h = func(pi) assert i(o(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 i(cos(x*y), y) == cosh(x) assert i(sin(x*y), y) == sinh(x)/I assert i(tan(x*y), y) == tanh(x)/I assert i(cot(x*y), y) == coth(x)*I assert i(sec(x*y), y) == 1/cosh(x) assert i(csc(x*y), y) == I/sinh(x)
def test_coth_rewrite(): x = Symbol('x') assert coth(x).rewrite(exp) == (exp(x) + exp(-x))/(exp(x) - exp(-x)) \ == coth(x).rewrite('tractable') assert coth(x).rewrite(sinh) == -I * sinh(I * pi / 2 - x) / sinh(x) assert coth(x).rewrite(cosh) == -I * cosh(x) / cosh(I * pi / 2 - x) assert coth(x).rewrite(tanh) == 1 / tanh(x)
def test_sinh_series(): assert sinh(x).series(x, 0, 10) == \ x + x**3/6 + x**5/120 + x**7/5040 + x**9/362880 + O(x**10) assert sinh(x).taylor_term(1, x) == x assert sinh(x).taylor_term(3, x) == x**3/6 assert sinh(x).taylor_term(3, x, *(x, 0)) == sinh(x).taylor_term(3, x)
def test_basic6(): # pull sympy/sympy#22491 assert limit(1/asin(x), x, 0) == oo assert limit(1/asin(x), x, 0, dir=1) == -oo assert limit(1/sinh(x), x, 0) == oo assert limit(1/sinh(x), x, 0, dir=1) == -oo assert limit(log(1/x) + 1/sin(x), x, 0) == oo assert limit(log(1/x) + 1/x, x, 0) == oo
def test_sinh_rewrite(): assert sinh(x).rewrite(exp) == (exp(x) - exp(-x))/2 \ == sinh(x).rewrite('tractable') assert sinh(x).rewrite(cosh) == -I * cosh(x + I * pi / 2) tanh_half = tanh(S.Half * x) assert sinh(x).rewrite(tanh) == 2 * tanh_half / (1 - tanh_half**2) coth_half = coth(S.Half * x) assert sinh(x).rewrite(coth) == 2 * coth_half / (coth_half**2 - 1)
def test_heurisch_hyperbolic(): assert heurisch(sinh(x), x) == cosh(x) assert heurisch(cosh(x), x) == sinh(x) assert heurisch(x*sinh(x), x) == x*cosh(x) - sinh(x) assert heurisch(x*cosh(x), x) == x*sinh(x) - cosh(x) assert heurisch( x*asinh(x/2), x) == x**2*asinh(x/2)/2 + asinh(x/2) - x*sqrt(4 + x**2)/4
def test_expint(): """ Test various exponential integrals. """ from diofant import (expint, unpolarify, Symbol, Ci, Si, Shi, Chi, sin, cos, sinh, cosh, Ei) assert simplify( unpolarify( integrate(exp(-z * x) / x**y, (x, 1, oo), meijerg=True, conds='none').rewrite(expint).expand( func=True))) == expint(y, z) assert integrate(exp(-z*x)/x, (x, 1, oo), meijerg=True, conds='none').rewrite(expint).expand() == \ expint(1, z) assert integrate(exp(-z*x)/x**2, (x, 1, oo), meijerg=True, conds='none').rewrite(expint).expand() == \ expint(2, z).rewrite(Ei).rewrite(expint) assert integrate(exp(-z*x)/x**3, (x, 1, oo), meijerg=True, conds='none').rewrite(expint).expand() == \ expint(3, z).rewrite(Ei).rewrite(expint).expand() t = Symbol('t', positive=True) assert integrate(-cos(x) / x, (x, t, oo), meijerg=True).expand() == Ci(t) assert integrate(-sin(x)/x, (x, t, oo), meijerg=True).expand() == \ Si(t) - pi/2 assert integrate(sin(x) / x, (x, 0, z), meijerg=True) == Si(z) assert integrate(sinh(x) / x, (x, 0, z), meijerg=True) == Shi(z) assert integrate(exp(-x)/x, x, meijerg=True).expand().rewrite(expint) == \ I*pi - expint(1, x) assert integrate(exp(-x)/x**2, x, meijerg=True).rewrite(expint).expand() \ == expint(1, x) - exp(-x)/x - I*pi u = Symbol('u', polar=True) assert integrate(cos(u)/u, u, meijerg=True).expand().as_independent(u)[1] \ == Ci(u) assert integrate(cosh(u)/u, u, meijerg=True).expand().as_independent(u)[1] \ == Chi(u) assert integrate( expint(1, x), x, meijerg=True).rewrite(expint).expand() == x * expint(1, x) - exp(-x) assert integrate(expint(2, x), x, meijerg=True ).rewrite(expint).expand() == \ -x**2*expint(1, x)/2 + x*exp(-x)/2 - exp(-x)/2 assert simplify(unpolarify(integrate(expint(y, x), x, meijerg=True).rewrite(expint).expand(func=True))) == \ -expint(y + 1, x) assert integrate(Si(x), x, meijerg=True) == x * Si(x) + cos(x) assert integrate(Ci(u), u, meijerg=True).expand() == u * Ci(u) - sin(u) assert integrate(Shi(x), x, meijerg=True) == x * Shi(x) - cosh(x) assert integrate(Chi(u), u, meijerg=True).expand() == u * Chi(u) - sinh(u) assert integrate(Si(x) * exp(-x), (x, 0, oo), meijerg=True) == pi / 4 assert integrate(expint(1, x) * sin(x), (x, 0, oo), meijerg=True) == log(2) / 2
def test_sympyissue_3210(): eqs = (sin(2)*cos(3) + sin(3)*cos(2), -sin(2)*sin(3) + cos(2)*cos(3), sin(2)*cos(3) - sin(3)*cos(2), sin(2)*sin(3) + cos(2)*cos(3), sin(2)*sin(3) + cos(2)*cos(3) + cos(2), sinh(2)*cosh(3) + sinh(3)*cosh(2), sinh(2)*sinh(3) + cosh(2)*cosh(3)) assert [trigsimp(e) for e in eqs] == [sin(5), cos(5), -sin(1), cos(1), cos(1) + cos(2), sinh(5), cosh(5)]
def test_heurisch_hyperbolic(): assert heurisch(sinh(x), x) == cosh(x) assert heurisch(cosh(x), x) == sinh(x) assert heurisch(x * sinh(x), x) == x * cosh(x) - sinh(x) assert heurisch(x * cosh(x), x) == x * sinh(x) - cosh(x) assert heurisch( x * asinh(x / 2), x) == x**2 * asinh(x / 2) / 2 + asinh(x / 2) - x * sqrt(4 + x**2) / 4
def test_derivs(): 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)
def test_derivs(): 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)
def test_sympyissue_8368_7173(): LT = laplace_transform # hyperbolic assert LT(sinh(x), x, s) == (1/(s**2 - 1), 1, True) assert LT(cosh(x), x, s) == (s/(s**2 - 1), 1, True) assert LT(sinh(x + 3), x, s) == ( (s*sinh(3) + cosh(3))/(s**2 - 1), 1, True) assert LT(sinh(x)*cosh(x), x, s) == (1/(s**2 - 4), 2, Ne(s/2, 1)) # trig (make sure they are not being rewritten in terms of exp) assert LT(cos(x + 3), x, s) == ((s*cos(3) - sin(3))/(s**2 + 1), 0, True)
def test_laplace_transform_2(): LT = laplace_transform # issue sympy/sympy#7173 assert LT(sinh(a*x)*cosh(a*x), x, s) == \ (a/(s**2 - 4*a**2), 0, And(Or(abs(periodic_argument(exp_polar(I*pi)*polar_lift(a), oo)) < pi/2, abs(periodic_argument(exp_polar(I*pi)*polar_lift(a), oo)) <= pi/2), Or(abs(periodic_argument(a, oo)) < pi/2, abs(periodic_argument(a, oo)) <= pi/2))) # issues sympy/sympy#8368 and sympy/sympy#7173 assert LT(sinh(x) * cosh(x), x, s) == (1 / (s**2 - 4), 2, Ne(s / 2, 1))
def test_issue_8368_7173(): LT = laplace_transform # hyperbolic assert LT(sinh(x), x, s) == (1 / (s**2 - 1), 1, True) assert LT(cosh(x), x, s) == (s / (s**2 - 1), 1, True) assert LT(sinh(x + 3), x, s) == ((s * sinh(3) + cosh(3)) / (s**2 - 1), 1, True) assert LT(sinh(x) * cosh(x), x, s) == (1 / (s**2 - 4), 2, Ne(s / 2, 1)) # trig (make sure they are not being rewritten in terms of exp) assert LT(cos(x + 3), x, s) == ((s * cos(3) - sin(3)) / (s**2 + 1), 0, True)
def test_trigsimp1a(): assert trigsimp(sin(2)**2*cos(3)*exp(2)/cos(2)**2) == tan(2)**2*cos(3)*exp(2) assert trigsimp(tan(2)**2*cos(3)*exp(2)*cos(2)**2) == sin(2)**2*cos(3)*exp(2) assert trigsimp(cot(2)*cos(3)*exp(2)*sin(2)) == cos(3)*exp(2)*cos(2) assert trigsimp(tan(2)*cos(3)*exp(2)/sin(2)) == cos(3)*exp(2)/cos(2) assert trigsimp(cot(2)*cos(3)*exp(2)/cos(2)) == cos(3)*exp(2)/sin(2) assert trigsimp(cot(2)*cos(3)*exp(2)*tan(2)) == cos(3)*exp(2) assert trigsimp(sinh(2)*cos(3)*exp(2)/cosh(2)) == tanh(2)*cos(3)*exp(2) assert trigsimp(tanh(2)*cos(3)*exp(2)*cosh(2)) == sinh(2)*cos(3)*exp(2) assert trigsimp(coth(2)*cos(3)*exp(2)*sinh(2)) == cosh(2)*cos(3)*exp(2) assert trigsimp(tanh(2)*cos(3)*exp(2)/sinh(2)) == cos(3)*exp(2)/cosh(2) assert trigsimp(coth(2)*cos(3)*exp(2)/cosh(2)) == cos(3)*exp(2)/sinh(2) assert trigsimp(coth(2)*cos(3)*exp(2)*tanh(2)) == cos(3)*exp(2)
def test_gruntz_hyperbolic(): assert gruntz(cosh(x), x) == oo assert gruntz(cosh(-x), x) == oo assert gruntz(sinh(x), x) == oo assert gruntz(sinh(-x), x) == -oo assert gruntz(2 * cosh(x) * exp(x), x) == oo assert gruntz(2 * cosh(-x) * exp(-x), x) == 1 assert gruntz(2 * sinh(x) * exp(x), x) == oo assert gruntz(2 * sinh(-x) * exp(-x), x) == -1 assert gruntz(tanh(x), x) == 1 assert gruntz(tanh(-x), x) == -1 assert gruntz(coth(x), x) == 1 assert gruntz(coth(-x), x) == -1
def test_gruntz_hyperbolic(): assert limit(cosh(x), x, oo) == oo assert limit(cosh(-x), x, oo) == oo assert limit(sinh(x), x, oo) == oo assert limit(sinh(-x), x, oo) == -oo assert limit(2*cosh(x)*exp(x), x, oo) == oo assert limit(2*cosh(-x)*exp(-x), x, oo) == 1 assert limit(2*sinh(x)*exp(x), x, oo) == oo assert limit(2*sinh(-x)*exp(-x), x, oo) == -1 assert limit(tanh(x), x, oo) == 1 assert limit(tanh(-x), x, oo) == -1 assert limit(coth(x), x, oo) == 1 assert limit(coth(-x), x, oo) == -1
def test_gruntz_hyperbolic(): assert gruntz(cosh(x), x) == oo assert gruntz(cosh(-x), x) == oo assert gruntz(sinh(x), x) == oo assert gruntz(sinh(-x), x) == -oo assert gruntz(2*cosh(x)*exp(x), x) == oo assert gruntz(2*cosh(-x)*exp(-x), x) == 1 assert gruntz(2*sinh(x)*exp(x), x) == oo assert gruntz(2*sinh(-x)*exp(-x), x) == -1 assert gruntz(tanh(x), x) == 1 assert gruntz(tanh(-x), x) == -1 assert gruntz(coth(x), x) == 1 assert gruntz(coth(-x), x) == -1
def test_expint(): """ Test various exponential integrals. """ assert simplify(integrate(exp(-z*x)/x**y, (x, 1, oo), meijerg=True, conds='none').rewrite(expint)) == expint(y, z) assert integrate(exp(-z*x)/x, (x, 1, oo), meijerg=True, conds='none').rewrite(expint).expand() == \ expint(1, z) assert integrate(exp(-z*x)/x**2, (x, 1, oo), meijerg=True, conds='none').rewrite(expint).expand() == \ expint(2, z).rewrite(Ei).rewrite(expint) assert integrate(exp(-z*x)/x**3, (x, 1, oo), meijerg=True, conds='none').rewrite(expint).expand() == \ expint(3, z).rewrite(Ei).rewrite(expint).expand() t = Symbol('t', positive=True) assert integrate(-cos(x)/x, (x, t, oo), meijerg=True).expand() == Ci(t) assert integrate(-sin(x)/x, (x, t, oo), meijerg=True).expand() == \ Si(t) - pi/2 assert integrate(sin(x)/x, (x, 0, z), meijerg=True) == Si(z) assert integrate(sinh(x)/x, (x, 0, z), meijerg=True) == Shi(z) assert integrate(exp(-x)/x, x, meijerg=True).expand().rewrite(expint) == \ I*pi - expint(1, x) assert integrate(exp(-x)/x**2, x, meijerg=True).rewrite(expint).expand() \ == expint(1, x) - exp(-x)/x - I*pi u = Symbol('u', polar=True) assert integrate(cos(u)/u, u, meijerg=True).expand().as_independent(u)[1] \ == Ci(u) assert integrate(cosh(u)/u, u, meijerg=True).expand().as_independent(u)[1] \ == Chi(u) assert (integrate(expint(1, x), x, meijerg=True).rewrite(expint).expand() == x*expint(1, x) - exp(-x)) assert (integrate(expint(2, x), x, meijerg=True).rewrite(expint).expand() == -x**2*expint(1, x)/2 + x*exp(-x)/2 - exp(-x)/2) assert (simplify(unpolarify(integrate(expint(y, x), x, meijerg=True).rewrite(expint))) == -expint(y + 1, x)) assert integrate(Si(x), x, meijerg=True) == x*Si(x) + cos(x) assert integrate(Ci(u), u, meijerg=True).expand() == u*Ci(u) - sin(u) assert integrate(Shi(x), x, meijerg=True) == x*Shi(x) - cosh(x) assert integrate(Chi(u), u, meijerg=True).expand() == u*Chi(u) - sinh(u) assert integrate(Si(x)*exp(-x), (x, 0, oo), meijerg=True) == pi/4 assert integrate(expint(1, x)*sin(x), (x, 0, oo), meijerg=True) == log(2)/2
def test_sympyissue_7173(): LT = laplace_transform # hyperbolic assert LT(sinh(x + 3), x, s) == ((s * sinh(3) + cosh(3)) / (s**2 - 1), 1, True) # trig (make sure they are not being rewritten in terms of exp) assert LT(cos(x + 3), x, s) == ((s * cos(3) - sin(3)) / (s**2 + 1), 0, True) t = symbols('t', real=True, positive=True) w = symbols('w', real=True) assert LT(sinh(w * t) * cosh(w * t), t, s)[0] == w / (s**2 - 4 * w**2)
def test_sinh_expansion(): x, y = symbols('x,y') assert sinh(x + y).expand(trig=True) == sinh(x) * cosh(y) + cosh(x) * sinh(y) assert sinh(2 * x).expand(trig=True) == 2 * sinh(x) * cosh(x) assert sinh(3*x).expand(trig=True).expand() == \ sinh(x)**3 + 3*sinh(x)*cosh(x)**2
def test_trigsimp_noncommutative(): A, B = symbols('A,B', commutative=False) assert trigsimp(A - A*sin(x)**2) == A*cos(x)**2 assert trigsimp(A - A*cos(x)**2) == A*sin(x)**2 assert trigsimp(A*sin(x)**2 + A*cos(x)**2) == A assert trigsimp(A + A*tan(x)**2) == A/cos(x)**2 assert trigsimp(A/cos(x)**2 - A) == A*tan(x)**2 assert trigsimp(A/cos(x)**2 - A*tan(x)**2) == A assert trigsimp(A + A*cot(x)**2) == A/sin(x)**2 assert trigsimp(A/sin(x)**2 - A) == A/tan(x)**2 assert trigsimp(A/sin(x)**2 - A*cot(x)**2) == A assert trigsimp(y*A*cos(x)**2 + y*A*sin(x)**2) == y*A assert trigsimp(A*sin(x)/cos(x)) == A*tan(x) assert trigsimp(A*tan(x)*cos(x)) == A*sin(x) assert trigsimp(A*cot(x)**3*sin(x)**3) == A*cos(x)**3 assert trigsimp(y*A*tan(x)**2/sin(x)**2) == y*A/cos(x)**2 assert trigsimp(A*cot(x)/cos(x)) == A/sin(x) assert trigsimp(A*sin(x + y) + A*sin(x - y)) == 2*A*sin(x)*cos(y) assert trigsimp(A*sin(x + y) - A*sin(x - y)) == 2*A*sin(y)*cos(x) assert trigsimp(A*cos(x + y) + A*cos(x - y)) == 2*A*cos(x)*cos(y) assert trigsimp(A*cos(x + y) - A*cos(x - y)) == -2*A*sin(x)*sin(y) assert trigsimp(A*sinh(x + y) + A*sinh(x - y)) == 2*A*sinh(x)*cosh(y) assert trigsimp(A*sinh(x + y) - A*sinh(x - y)) == 2*A*sinh(y)*cosh(x) assert trigsimp(A*cosh(x + y) + A*cosh(x - y)) == 2*A*cosh(x)*cosh(y) assert trigsimp(A*cosh(x + y) - A*cosh(x - y)) == 2*A*sinh(x)*sinh(y) assert trigsimp(A*cos(0.12345)**2 + A*sin(0.12345)**2) == 1.0*A
def test_sympyissue_3210(): eqs = (sin(2) * cos(3) + sin(3) * cos(2), -sin(2) * sin(3) + cos(2) * cos(3), sin(2) * cos(3) - sin(3) * cos(2), sin(2) * sin(3) + cos(2) * cos(3), sin(2) * sin(3) + cos(2) * cos(3) + cos(2), sinh(2) * cosh(3) + sinh(3) * cosh(2), sinh(2) * sinh(3) + cosh(2) * cosh(3)) assert [trigsimp(e) for e in eqs] == [ sin(5), cos(5), -sin(1), cos(1), cos(1) + cos(2), sinh(5), cosh(5) ]
def test_intrinsic_math1_codegen(): # not included: log10 name_expr = [ ("test_fabs", abs(x)), ("test_acos", acos(x)), ("test_asin", asin(x)), ("test_atan", atan(x)), ("test_cos", cos(x)), ("test_cosh", cosh(x)), ("test_log", log(x)), ("test_ln", ln(x)), ("test_sin", sin(x)), ("test_sinh", sinh(x)), ("test_sqrt", sqrt(x)), ("test_tan", tan(x)), ("test_tanh", tanh(x)), ] numerical_tests = [] for name, expr in name_expr: for xval in 0.2, 0.5, 0.8: expected = N(expr.subs(x, xval), strict=False) numerical_tests.append((name, (xval, ), expected, 1e-14)) for lang, commands in valid_lang_commands: if lang == "C": name_expr_C = [("test_floor", floor(x)), ("test_ceil", ceiling(x))] else: name_expr_C = [] run_test("intrinsic_math1", name_expr + name_expr_C, numerical_tests, lang, commands)
def test_issue_7173(): assert laplace_transform(sinh(a*x)*cosh(a*x), x, s) == \ (a/(s**2 - 4*a**2), 0, And(Or(Abs(periodic_argument(exp_polar(I*pi)*polar_lift(a), oo)) < pi/2, Abs(periodic_argument(exp_polar(I*pi)*polar_lift(a), oo)) <= pi/2), Or(Abs(periodic_argument(a, oo)) < pi/2, Abs(periodic_argument(a, oo)) <= pi/2)))
def test_intrinsic_math1_codegen(): # not included: log10 name_expr = [ ('test_fabs', abs(x)), ('test_acos', acos(x)), ('test_asin', asin(x)), ('test_atan', atan(x)), ('test_cos', cos(x)), ('test_cosh', cosh(x)), ('test_log', log(x)), ('test_ln', ln(x)), ('test_sin', sin(x)), ('test_sinh', sinh(x)), ('test_sqrt', sqrt(x)), ('test_tan', tan(x)), ('test_tanh', tanh(x)), ] numerical_tests = [] for name, expr in name_expr: for xval in 0.2, 0.5, 0.8: expected = N(expr.subs({x: xval}), strict=False) numerical_tests.append((name, (xval, ), expected, 1e-14)) for lang, commands in valid_lang_commands: if lang == 'C': name_expr_C = [('test_floor', floor(x)), ('test_ceil', ceiling(x))] else: name_expr_C = [] run_test('intrinsic_math1', name_expr + name_expr_C, numerical_tests, lang, commands)
def test_real_imag(): a, b = symbols('a b', extended_real=True) z = a + b*I for deep in [True, False]: assert sin( z).as_real_imag(deep=deep) == (sin(a)*cosh(b), cos(a)*sinh(b)) assert cos( z).as_real_imag(deep=deep) == (cos(a)*cosh(b), -sin(a)*sinh(b)) assert tan(z).as_real_imag(deep=deep) == (sin(2*a)/(cos(2*a) + cosh(2*b)), sinh(2*b)/(cos(2*a) + cosh(2*b))) assert cot(z).as_real_imag(deep=deep) == (-sin(2*a)/(cos(2*a) - cosh(2*b)), -sinh(2*b)/(cos(2*a) - cosh(2*b))) assert sin(a).as_real_imag(deep=deep) == (sin(a), 0) assert cos(a).as_real_imag(deep=deep) == (cos(a), 0) assert tan(a).as_real_imag(deep=deep) == (tan(a), 0) assert cot(a).as_real_imag(deep=deep) == (cot(a), 0)
def test_sympyissue_7173(): assert laplace_transform(sinh(a*x)*cosh(a*x), x, s) == \ (a/(s**2 - 4*a**2), 0, And(Or(Abs(periodic_argument(exp_polar(I*pi)*polar_lift(a), oo)) < pi/2, Abs(periodic_argument(exp_polar(I*pi)*polar_lift(a), oo)) <= pi/2), Or(Abs(periodic_argument(a, oo)) < pi/2, Abs(periodic_argument(a, oo)) <= pi/2)))
def test_intrinsic_math1_codegen(): # not included: log10 name_expr = [ ("test_fabs", abs(x)), ("test_acos", acos(x)), ("test_asin", asin(x)), ("test_atan", atan(x)), ("test_cos", cos(x)), ("test_cosh", cosh(x)), ("test_log", log(x)), ("test_ln", ln(x)), ("test_sin", sin(x)), ("test_sinh", sinh(x)), ("test_sqrt", sqrt(x)), ("test_tan", tan(x)), ("test_tanh", tanh(x)), ] numerical_tests = [] for name, expr in name_expr: for xval in 0.2, 0.5, 0.8: expected = N(expr.subs({x: xval}), strict=False) numerical_tests.append((name, (xval,), expected, 1e-14)) for lang, commands in valid_lang_commands: if lang == "C": name_expr_C = [("test_floor", floor(x)), ("test_ceil", ceiling(x))] else: name_expr_C = [] run_test("intrinsic_math1", name_expr + name_expr_C, numerical_tests, lang, commands)
def test_cosh_rewrite(): assert cosh(x).rewrite(exp) == (exp(x) + exp(-x))/2 \ == cosh(x).rewrite('tractable') assert cosh(x).rewrite(sinh) == -I * sinh(x + I * pi / 2) tanh_half = tanh(S.Half * x)**2 assert cosh(x).rewrite(tanh) == (1 + tanh_half) / (1 - tanh_half) coth_half = coth(S.Half * x)**2 assert cosh(x).rewrite(coth) == (coth_half + 1) / (coth_half - 1)
def test_sympyissue_21029(): e = (sinh(x) + cosh(x) - 1)/x/4 ans0 = Rational(1, 4) ansz = (exp(z) - 1)/z/4 assert limit(e, x, 0) == ans0 assert limit(e, x, z) == ansz assert limit(ansz, z, 0) == ans0
def test_sech_rewrite(): 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_sympyissue_8368(): assert integrate(exp(-s*x)*cosh(x), (x, 0, oo)) == \ Piecewise((pi*Piecewise((-s/(pi*(-s**2 + 1)), Abs(s**2) < 1), (1/(pi*s*(1 - 1/s**2)), Abs(s**(-2)) < 1), (meijerg(((Rational(1, 2),), (0, 0)), ((0, Rational(1, 2)), (0,)), polar_lift(s)**2), True)), And(Abs(periodic_argument(polar_lift(s)**2, oo)) < pi, Ne(s**2, 1), cos(Abs(periodic_argument(polar_lift(s)**2, oo))/2)*sqrt(Abs(s**2)) - 1 > 0)), (Integral(exp(-s*x)*cosh(x), (x, 0, oo)), True)) assert integrate(exp(-s*x)*sinh(x), (x, 0, oo)) == \ Piecewise((pi*Piecewise((2/(pi*(2*s**2 - 2)), Abs(s**2) < 1), (-2/(pi*s**2*(-2 + 2/s**2)), Abs(s**(-2)) < 1), (meijerg(((0,), (Rational(-1, 2), Rational(1, 2))), ((0, Rational(1, 2)), (Rational(-1, 2),)), polar_lift(s)**2), True)), And(Abs(periodic_argument(polar_lift(s)**2, oo)) < pi, Ne(s**2, 1), cos(Abs(periodic_argument(polar_lift(s)**2, oo))/2)*sqrt(Abs(s**2)) - 1 > 0)), (Integral(E**(-s*x)*sinh(x), (x, 0, oo)), True))
def test_inverses(): assert sinh(x).inverse() == asinh pytest.raises(AttributeError, lambda: cosh(x).inverse()) assert tanh(x).inverse() == atanh assert coth(x).inverse() == acoth assert asinh(x).inverse() == sinh assert acosh(x).inverse() == cosh assert atanh(x).inverse() == tanh assert acoth(x).inverse() == coth
def test_hyperbolic(): assert sinh(x).nseries(x, n=6) == x + x**3/6 + x**5/120 + O(x**7) assert cosh(x).nseries(x, n=5) == 1 + x**2/2 + x**4/24 + O(x**6) assert tanh(x).nseries(x, n=6) == x - x**3/3 + 2*x**5/15 + O(x**7) assert coth(x).nseries(x, n=6) == \ 1/x - x**3/45 + x/3 + 2*x**5/945 + O(x**7) assert asinh(x).nseries(x, n=6) == x - x**3/6 + 3*x**5/40 + O(x**7) assert acosh(x).nseries(x, n=6) == \ pi*I/2 - I*x - 3*I*x**5/40 - I*x**3/6 + O(x**7) assert atanh(x).nseries(x, n=6) == x + x**3/3 + x**5/5 + O(x**7) assert acoth(x).nseries(x, n=6) == x + x**3/3 + x**5/5 + pi*I/2 + O(x**7)
def test_conjugate(): a = Symbol("a", extended_real=True) b = Symbol("b", extended_real=True) c = Symbol("c", imaginary=True) d = Symbol("d", imaginary=True) x = Symbol('x') z = a + I*b + c + I*d zc = a - I*b - c + I*d assert conjugate(z) == zc assert conjugate(exp(z)) == exp(zc) assert conjugate(exp(I*x)) == exp(-I*conjugate(x)) assert conjugate(z**5) == zc**5 assert conjugate(abs(x)) == abs(x) assert conjugate(sign(z)) == sign(zc) assert conjugate(sin(z)) == sin(zc) assert conjugate(cos(z)) == cos(zc) assert conjugate(tan(z)) == tan(zc) assert conjugate(cot(z)) == cot(zc) assert conjugate(sinh(z)) == sinh(zc) assert conjugate(cosh(z)) == cosh(zc) assert conjugate(tanh(z)) == tanh(zc) assert conjugate(coth(z)) == coth(zc)
def test_evalc(): x = Symbol("x", extended_real=True) y = Symbol("y", extended_real=True) z = Symbol("z") assert ((x + I*y)**2).expand(complex=True) == x**2 + 2*I*x*y - y**2 assert expand_complex(z**(2*I)) == (re((re(z) + I*im(z))**(2*I)) + I*im((re(z) + I*im(z))**(2*I))) assert expand_complex( z**(2*I), deep=False) == I*im(z**(2*I)) + re(z**(2*I)) assert exp(I*x) != cos(x) + I*sin(x) assert exp(I*x).expand(complex=True) == cos(x) + I*sin(x) assert exp(I*x + y).expand(complex=True) == exp(y)*cos(x) + I*sin(x)*exp(y) assert sin(I*x).expand(complex=True) == I * sinh(x) assert sin(x + I*y).expand(complex=True) == sin(x)*cosh(y) + \ I * sinh(y) * cos(x) assert cos(I*x).expand(complex=True) == cosh(x) assert cos(x + I*y).expand(complex=True) == cos(x)*cosh(y) - \ I * sinh(y) * sin(x) assert tan(I*x).expand(complex=True) == tanh(x) * I assert tan(x + I*y).expand(complex=True) == ( sin(2*x)/(cos(2*x) + cosh(2*y)) + I*sinh(2*y)/(cos(2*x) + cosh(2*y))) assert sinh(I*x).expand(complex=True) == I * sin(x) assert sinh(x + I*y).expand(complex=True) == sinh(x)*cos(y) + \ I * sin(y) * cosh(x) assert cosh(I*x).expand(complex=True) == cos(x) assert cosh(x + I*y).expand(complex=True) == cosh(x)*cos(y) + \ I * sin(y) * sinh(x) assert tanh(I*x).expand(complex=True) == tan(x) * I assert tanh(x + I*y).expand(complex=True) == ( (sinh(x)*cosh(x) + I*cos(y)*sin(y)) / (sinh(x)**2 + cos(y)**2)).expand()
def test_ansi_math1_codegen(): # not included: log10 name_expr = [ ("test_fabs", Abs(x)), ("test_acos", acos(x)), ("test_asin", asin(x)), ("test_atan", atan(x)), ("test_ceil", ceiling(x)), ("test_cos", cos(x)), ("test_cosh", cosh(x)), ("test_floor", floor(x)), ("test_log", log(x)), ("test_ln", ln(x)), ("test_sin", sin(x)), ("test_sinh", sinh(x)), ("test_sqrt", sqrt(x)), ("test_tan", tan(x)), ("test_tanh", tanh(x)), ] result = codegen(name_expr, "C", "file", header=False, empty=False) assert result[0][0] == "file.c" assert result[0][1] == ( '#include "file.h"\n#include <math.h>\n' 'double test_fabs(double x) {\n double test_fabs_result;\n test_fabs_result = fabs(x);\n return test_fabs_result;\n}\n' 'double test_acos(double x) {\n double test_acos_result;\n test_acos_result = acos(x);\n return test_acos_result;\n}\n' 'double test_asin(double x) {\n double test_asin_result;\n test_asin_result = asin(x);\n return test_asin_result;\n}\n' 'double test_atan(double x) {\n double test_atan_result;\n test_atan_result = atan(x);\n return test_atan_result;\n}\n' 'double test_ceil(double x) {\n double test_ceil_result;\n test_ceil_result = ceil(x);\n return test_ceil_result;\n}\n' 'double test_cos(double x) {\n double test_cos_result;\n test_cos_result = cos(x);\n return test_cos_result;\n}\n' 'double test_cosh(double x) {\n double test_cosh_result;\n test_cosh_result = cosh(x);\n return test_cosh_result;\n}\n' 'double test_floor(double x) {\n double test_floor_result;\n test_floor_result = floor(x);\n return test_floor_result;\n}\n' 'double test_log(double x) {\n double test_log_result;\n test_log_result = log(x);\n return test_log_result;\n}\n' 'double test_ln(double x) {\n double test_ln_result;\n test_ln_result = log(x);\n return test_ln_result;\n}\n' 'double test_sin(double x) {\n double test_sin_result;\n test_sin_result = sin(x);\n return test_sin_result;\n}\n' 'double test_sinh(double x) {\n double test_sinh_result;\n test_sinh_result = sinh(x);\n return test_sinh_result;\n}\n' 'double test_sqrt(double x) {\n double test_sqrt_result;\n test_sqrt_result = sqrt(x);\n return test_sqrt_result;\n}\n' 'double test_tan(double x) {\n double test_tan_result;\n test_tan_result = tan(x);\n return test_tan_result;\n}\n' 'double test_tanh(double x) {\n double test_tanh_result;\n test_tanh_result = tanh(x);\n return test_tanh_result;\n}\n' ) assert result[1][0] == "file.h" assert result[1][1] == ( '#ifndef PROJECT__FILE__H\n#define PROJECT__FILE__H\n' 'double test_fabs(double x);\ndouble test_acos(double x);\n' 'double test_asin(double x);\ndouble test_atan(double x);\n' 'double test_ceil(double x);\ndouble test_cos(double x);\n' 'double test_cosh(double x);\ndouble test_floor(double x);\n' 'double test_log(double x);\ndouble test_ln(double x);\n' 'double test_sin(double x);\ndouble test_sinh(double x);\n' 'double test_sqrt(double x);\ndouble test_tan(double x);\n' 'double test_tanh(double x);\n#endif\n' )
def test_trigsimp1(): assert trigsimp(1 - sin(x)**2) == cos(x)**2 assert trigsimp(1 - cos(x)**2) == sin(x)**2 assert trigsimp(sin(x)**2 + cos(x)**2) == 1 assert trigsimp(1 + tan(x)**2) == 1/cos(x)**2 assert trigsimp(1/cos(x)**2 - 1) == tan(x)**2 assert trigsimp(1/cos(x)**2 - tan(x)**2) == 1 assert trigsimp(1 + cot(x)**2) == 1/sin(x)**2 assert trigsimp(1/sin(x)**2 - 1) == 1/tan(x)**2 assert trigsimp(1/sin(x)**2 - cot(x)**2) == 1 assert trigsimp(5*cos(x)**2 + 5*sin(x)**2) == 5 assert trigsimp(5*cos(x/2)**2 + 2*sin(x/2)**2) == 3*cos(x)/2 + Rational(7, 2) assert trigsimp(sin(x)/cos(x)) == tan(x) assert trigsimp(2*tan(x)*cos(x)) == 2*sin(x) assert trigsimp(cot(x)**3*sin(x)**3) == cos(x)**3 assert trigsimp(y*tan(x)**2/sin(x)**2) == y/cos(x)**2 assert trigsimp(cot(x)/cos(x)) == 1/sin(x) assert trigsimp(sin(x + y) + sin(x - y)) == 2*sin(x)*cos(y) assert trigsimp(sin(x + y) - sin(x - y)) == 2*sin(y)*cos(x) assert trigsimp(cos(x + y) + cos(x - y)) == 2*cos(x)*cos(y) assert trigsimp(cos(x + y) - cos(x - y)) == -2*sin(x)*sin(y) assert trigsimp(tan(x + y) - tan(x)/(1 - tan(x)*tan(y))) == \ sin(y)/(-sin(y)*tan(x) + cos(y)) # -tan(y)/(tan(x)*tan(y) - 1) assert trigsimp(sinh(x + y) + sinh(x - y)) == 2*sinh(x)*cosh(y) assert trigsimp(sinh(x + y) - sinh(x - y)) == 2*sinh(y)*cosh(x) assert trigsimp(cosh(x + y) + cosh(x - y)) == 2*cosh(x)*cosh(y) assert trigsimp(cosh(x + y) - cosh(x - y)) == 2*sinh(x)*sinh(y) assert trigsimp(tanh(x + y) - tanh(x)/(1 + tanh(x)*tanh(y))) == \ sinh(y)/(sinh(y)*tanh(x) + cosh(y)) assert trigsimp(cos(0.12345)**2 + sin(0.12345)**2) == 1 e = 2*sin(x)**2 + 2*cos(x)**2 assert trigsimp(log(e)) == log(2)
def test_hyper_as_trig(): 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 o(sinh(x), d) == I*sin(x*d) assert o(tanh(x), d) == I*tan(x*d) assert o(coth(x), d) == cot(x*d)/I assert o(cosh(x), d) == cos(x*d) for func in (sinh, cosh, tanh, coth): h = func(pi) assert i(o(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 i(cos(x*y), y) == cosh(x) assert i(sin(x*y), y) == sinh(x)/I assert i(tan(x*y), y) == tanh(x)/I assert i(cot(x*y), y) == coth(x)*I assert i(sec(x*y), y) == 1/cosh(x) assert i(csc(x*y), y) == I/sinh(x)
def test_basic5(): class my(Function): @classmethod def eval(cls, arg): if arg is oo: return nan assert limit(my(x), x, oo) == Limit(my(x), x, oo) assert limit(4/x > 8, x, 0) # relational test assert limit(my(x) > 0, x, oo) == Limit(my(x) > 0, x, oo) # from https://groups.google.com/forum/#!topic/sympy/LkTMQKC_BOw # fix bisected to ade6d20 and c459d18 a = Symbol('a', positive=True) f = exp(x*(-a - 1)) * sinh(x) assert limit(f, x, oo) == 0 assert limit(O(x), x, x**2) == Limit(O(x), x, x**2)
def test_inverse_laplace_transform(): ILT = inverse_laplace_transform a, b, c, = symbols('a b c', positive=True, finite=True) def simp_hyp(expr): return factor_terms(expand_mul(expr)).rewrite(sin) # just test inverses of all of the above assert ILT(1/s, s, t) == Heaviside(t) assert ILT(1/s**2, s, t) == t*Heaviside(t) assert ILT(1/s**5, s, t) == t**4*Heaviside(t)/24 assert ILT(exp(-a*s)/s, s, t) == Heaviside(t - a) assert ILT(exp(-a*s)/(s + b), s, t) == exp(b*(a - t))*Heaviside(-a + t) assert ILT(a/(s**2 + a**2), s, t) == sin(a*t)*Heaviside(t) assert ILT(s/(s**2 + a**2), s, t) == cos(a*t)*Heaviside(t) # TODO is there a way around simp_hyp? assert simp_hyp(ILT(a/(s**2 - a**2), s, t)) == sinh(a*t)*Heaviside(t) assert simp_hyp(ILT(s/(s**2 - a**2), s, t)) == cosh(a*t)*Heaviside(t) assert ILT(a/((s + b)**2 + a**2), s, t) == exp(-b*t)*sin(a*t)*Heaviside(t) assert ILT( (s + b)/((s + b)**2 + a**2), s, t) == exp(-b*t)*cos(a*t)*Heaviside(t) # TODO sinh/cosh shifted come out a mess. also delayed trig is a mess # TODO should this simplify further? assert ILT(exp(-a*s)/s**b, s, t) == \ (t - a)**(b - 1)*Heaviside(t - a)/gamma(b) assert ILT(exp(-a*s)/sqrt(1 + s**2), s, t) == \ Heaviside(t - a)*besselj(0, a - t) # note: besselj(0, x) is even # XXX ILT turns these branch factor into trig functions ... assert simplify(ILT(a**b*(s + sqrt(s**2 - a**2))**(-b)/sqrt(s**2 - a**2), s, t).rewrite(exp)) == \ Heaviside(t)*besseli(b, a*t) assert ILT(a**b*(s + sqrt(s**2 + a**2))**(-b)/sqrt(s**2 + a**2), s, t).rewrite(exp) == \ Heaviside(t)*besselj(b, a*t) assert ILT(1/(s*sqrt(s + 1)), s, t) == Heaviside(t)*erf(sqrt(t)) # TODO can we make erf(t) work? assert ILT(1/(s**2*(s**2 + 1)), s, t) == (t - sin(t))*Heaviside(t) assert ILT( (s * eye(2) - Matrix([[1, 0], [0, 2]])).inv(), s, t) ==\ Matrix([[exp(t)*Heaviside(t), 0], [0, exp(2*t)*Heaviside(t)]])
def test_si(): assert Si(I*x) == I*Shi(x) assert Shi(I*x) == I*Si(x) assert Si(-I*x) == -I*Shi(x) assert Shi(-I*x) == -I*Si(x) assert Si(-x) == -Si(x) assert Shi(-x) == -Shi(x) assert Si(exp_polar(2*pi*I)*x) == Si(x) assert Si(exp_polar(-2*pi*I)*x) == Si(x) assert Shi(exp_polar(2*pi*I)*x) == Shi(x) assert Shi(exp_polar(-2*pi*I)*x) == Shi(x) assert Si(oo) == pi/2 assert Si(-oo) == -pi/2 assert Shi(oo) == oo assert Shi(-oo) == -oo assert mytd(Si(x), sin(x)/x, x) assert mytd(Shi(x), sinh(x)/x, x) assert mytn(Si(x), Si(x).rewrite(Ei), -I*(-Ei(x*exp_polar(-I*pi/2))/2 + Ei(x*exp_polar(I*pi/2))/2 - I*pi) + pi/2, x) assert mytn(Si(x), Si(x).rewrite(expint), -I*(-expint(1, x*exp_polar(-I*pi/2))/2 + expint(1, x*exp_polar(I*pi/2))/2) + pi/2, x) assert mytn(Shi(x), Shi(x).rewrite(Ei), Ei(x)/2 - Ei(x*exp_polar(I*pi))/2 + I*pi/2, x) assert mytn(Shi(x), Shi(x).rewrite(expint), expint(1, x)/2 - expint(1, x*exp_polar(I*pi))/2 - I*pi/2, x) assert tn_arg(Si) assert tn_arg(Shi) assert Si(x).nseries(x, n=8) == \ x - x**3/18 + x**5/600 - x**7/35280 + O(x**9) assert Shi(x).nseries(x, n=8) == \ x + x**3/18 + x**5/600 + x**7/35280 + O(x**9) assert Si(sin(x)).nseries(x, n=5) == x - 2*x**3/9 + 17*x**5/450 + O(x**7) assert Si(x).series(x, 1, n=3) == \ Si(1) + (x - 1)*sin(1) + (x - 1)**2*(-sin(1)/2 + cos(1)/2) + O((x - 1)**3, (x, 1)) pytest.raises(ArgumentIndexError, lambda: Si(z).fdiff(2))
def test_mathml_trig(): mml = mp._print(sin(x)) assert mml.childNodes[0].nodeName == 'sin' mml = mp._print(cos(x)) assert mml.childNodes[0].nodeName == 'cos' mml = mp._print(tan(x)) assert mml.childNodes[0].nodeName == 'tan' mml = mp._print(asin(x)) assert mml.childNodes[0].nodeName == 'arcsin' mml = mp._print(acos(x)) assert mml.childNodes[0].nodeName == 'arccos' mml = mp._print(atan(x)) assert mml.childNodes[0].nodeName == 'arctan' mml = mp._print(sinh(x)) assert mml.childNodes[0].nodeName == 'sinh' mml = mp._print(cosh(x)) assert mml.childNodes[0].nodeName == 'cosh' mml = mp._print(tanh(x)) assert mml.childNodes[0].nodeName == 'tanh' mml = mp._print(asinh(x)) assert mml.childNodes[0].nodeName == 'arcsinh' mml = mp._print(atanh(x)) assert mml.childNodes[0].nodeName == 'arctanh' mml = mp._print(acosh(x)) assert mml.childNodes[0].nodeName == 'arccosh'
def test_exptrigsimp(): def valid(a, b): if not (tn(a, b) and a == b): return False return True assert exptrigsimp(exp(x) + exp(-x)) == 2*cosh(x) assert exptrigsimp(exp(x) - exp(-x)) == 2*sinh(x) e = [cos(x) + I*sin(x), cos(x) - I*sin(x), cosh(x) - sinh(x), cosh(x) + sinh(x)] ok = [exp(I*x), exp(-I*x), exp(-x), exp(x)] assert all(valid(i, j) for i, j in zip( [exptrigsimp(ei) for ei in e], ok)) ue = [cos(x) + sin(x), cos(x) - sin(x), cosh(x) + I*sinh(x), cosh(x) - I*sinh(x)] assert [exptrigsimp(ei) == ei for ei in ue] res = [] ok = [y*tanh(1), 1/(y*tanh(1)), I*y*tan(1), -I/(y*tan(1)), y*tanh(x), 1/(y*tanh(x)), I*y*tan(x), -I/(y*tan(x)), y*tanh(1 + I), 1/(y*tanh(1 + I))] for a in (1, I, x, I*x, 1 + I): w = exp(a) eq = y*(w - 1/w)/(w + 1/w) s = simplify(eq) assert s == exptrigsimp(eq) res.append(s) sinv = simplify(1/eq) assert sinv == exptrigsimp(1/eq) res.append(sinv) assert all(valid(i, j) for i, j in zip(res, ok)) for a in range(1, 3): w = exp(a) e = w + 1/w s = simplify(e) assert s == exptrigsimp(e) assert valid(s, 2*cosh(a)) e = w - 1/w s = simplify(e) assert s == exptrigsimp(e) assert valid(s, 2*sinh(a))
def test_sympyissue_5236(): assert (cos(1 + I)**3).as_real_imag() == (-3*sin(1)**2*sinh(1)**2*cos(1)*cosh(1) + cos(1)**3*cosh(1)**3, -3*cos(1)**2*cosh(1)**2*sin(1)*sinh(1) + sin(1)**3*sinh(1)**3)
def test_exp_rewrite(): assert exp(x).rewrite(sin) == sinh(x) + cosh(x) assert exp(x*I).rewrite(cos) == cos(x) + I*sin(x) assert exp(1).rewrite(cos) == sinh(1) + cosh(1) assert exp(1).rewrite(sin) == sinh(1) + cosh(1) assert exp(x).rewrite(tanh) == (1 + tanh(x/2))/(1 - tanh(x/2))
def test_cosh_expansion(): assert cosh(x+y).expand(trig=True) == cosh(x)*cosh(y) + sinh(x)*sinh(y) assert cosh(2*x).expand(trig=True) == cosh(x)**2 + sinh(x)**2 assert cosh(3*x).expand(trig=True).expand() == \ 3*sinh(x)**2*cosh(x) + cosh(x)**3
def test_sinh_expansion(): assert sinh(x+y).expand(trig=True) == sinh(x)*cosh(y) + cosh(x)*sinh(y) assert sinh(2*x).expand(trig=True) == 2*sinh(x)*cosh(x) assert sinh(3*x).expand(trig=True).expand() == \ sinh(x)**3 + 3*sinh(x)*cosh(x)**2