%PDF- %PDF-
Direktori : /usr/lib/python3/dist-packages/sympy/simplify/tests/ |
Current File : //usr/lib/python3/dist-packages/sympy/simplify/tests/test_simplify.py |
from sympy import ( Abs, acos, Add, asin, atan, Basic, binomial, besselsimp, cos, cosh, count_ops, csch, diff, E, Eq, erf, exp, exp_polar, expand, expand_multinomial, factor, factorial, Float, Function, gamma, GoldenRatio, hyper, hypersimp, I, Integral, integrate, KroneckerDelta, log, logcombine, Lt, Matrix, MatrixSymbol, Mul, nsimplify, oo, pi, Piecewise, Poly, posify, rad, Rational, S, separatevars, signsimp, simplify, sign, sin, sinc, sinh, solve, sqrt, Sum, Symbol, symbols, sympify, tan, zoo, And, Gt, Ge, Le, Or) from sympy.core.mul import _keep_coeff from sympy.core.expr import unchanged from sympy.simplify.simplify import nthroot, inversecombine from sympy.testing.pytest import XFAIL, slow, _both_exp_pow from sympy.abc import x, y, z, t, a, b, c, d, e, f, g, h, i, n def test_issue_7263(): assert abs((simplify(30.8**2 - 82.5**2 * sin(rad(11.6))**2)).evalf() - \ 673.447451402970) < 1e-12 def test_factorial_simplify(): # There are more tests in test_factorials.py. x = Symbol('x') assert simplify(factorial(x)/x) == gamma(x) assert simplify(factorial(factorial(x))) == factorial(factorial(x)) def test_simplify_expr(): x, y, z, k, n, m, w, s, A = symbols('x,y,z,k,n,m,w,s,A') f = Function('f') assert all(simplify(tmp) == tmp for tmp in [I, E, oo, x, -x, -oo, -E, -I]) e = 1/x + 1/y assert e != (x + y)/(x*y) assert simplify(e) == (x + y)/(x*y) e = A**2*s**4/(4*pi*k*m**3) assert simplify(e) == e e = (4 + 4*x - 2*(2 + 2*x))/(2 + 2*x) assert simplify(e) == 0 e = (-4*x*y**2 - 2*y**3 - 2*x**2*y)/(x + y)**2 assert simplify(e) == -2*y e = -x - y - (x + y)**(-1)*y**2 + (x + y)**(-1)*x**2 assert simplify(e) == -2*y e = (x + x*y)/x assert simplify(e) == 1 + y e = (f(x) + y*f(x))/f(x) assert simplify(e) == 1 + y e = (2 * (1/n - cos(n * pi)/n))/pi assert simplify(e) == (-cos(pi*n) + 1)/(pi*n)*2 e = integrate(1/(x**3 + 1), x).diff(x) assert simplify(e) == 1/(x**3 + 1) e = integrate(x/(x**2 + 3*x + 1), x).diff(x) assert simplify(e) == x/(x**2 + 3*x + 1) f = Symbol('f') A = Matrix([[2*k - m*w**2, -k], [-k, k - m*w**2]]).inv() assert simplify((A*Matrix([0, f]))[1] - (-f*(2*k - m*w**2)/(k**2 - (k - m*w**2)*(2*k - m*w**2)))) == 0 f = -x + y/(z + t) + z*x/(z + t) + z*a/(z + t) + t*x/(z + t) assert simplify(f) == (y + a*z)/(z + t) # issue 10347 expr = -x*(y**2 - 1)*(2*y**2*(x**2 - 1)/(a*(x**2 - y**2)**2) + (x**2 - 1) /(a*(x**2 - y**2)))/(a*(x**2 - y**2)) + x*(-2*x**2*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*sin(z)/(a*(x**2 - y**2)**2) - x**2*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*sin(z)/(a*(x**2 - 1)*(x**2 - y**2)) + (x**2*sqrt((-x**2 + 1)* (y**2 - 1))*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*sin(z)/(x**2 - 1) + sqrt( (-x**2 + 1)*(y**2 - 1))*(x*(-x*y**2 + x)/sqrt(-x**2*y**2 + x**2 + y**2 - 1) + sqrt(-x**2*y**2 + x**2 + y**2 - 1))*sin(z))/(a*sqrt((-x**2 + 1)*( y**2 - 1))*(x**2 - y**2)))*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*sin(z)/(a* (x**2 - y**2)) + x*(-2*x**2*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*cos(z)/(a* (x**2 - y**2)**2) - x**2*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*cos(z)/(a* (x**2 - 1)*(x**2 - y**2)) + (x**2*sqrt((-x**2 + 1)*(y**2 - 1))*sqrt(-x**2 *y**2 + x**2 + y**2 - 1)*cos(z)/(x**2 - 1) + x*sqrt((-x**2 + 1)*(y**2 - 1))*(-x*y**2 + x)*cos(z)/sqrt(-x**2*y**2 + x**2 + y**2 - 1) + sqrt((-x**2 + 1)*(y**2 - 1))*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*cos(z))/(a*sqrt((-x**2 + 1)*(y**2 - 1))*(x**2 - y**2)))*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*cos( z)/(a*(x**2 - y**2)) - y*sqrt((-x**2 + 1)*(y**2 - 1))*(-x*y*sqrt(-x**2* y**2 + x**2 + y**2 - 1)*sin(z)/(a*(x**2 - y**2)*(y**2 - 1)) + 2*x*y*sqrt( -x**2*y**2 + x**2 + y**2 - 1)*sin(z)/(a*(x**2 - y**2)**2) + (x*y*sqrt(( -x**2 + 1)*(y**2 - 1))*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*sin(z)/(y**2 - 1) + x*sqrt((-x**2 + 1)*(y**2 - 1))*(-x**2*y + y)*sin(z)/sqrt(-x**2*y**2 + x**2 + y**2 - 1))/(a*sqrt((-x**2 + 1)*(y**2 - 1))*(x**2 - y**2)))*sin( z)/(a*(x**2 - y**2)) + y*(x**2 - 1)*(-2*x*y*(x**2 - 1)/(a*(x**2 - y**2) **2) + 2*x*y/(a*(x**2 - y**2)))/(a*(x**2 - y**2)) + y*(x**2 - 1)*(y**2 - 1)*(-x*y*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*cos(z)/(a*(x**2 - y**2)*(y**2 - 1)) + 2*x*y*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*cos(z)/(a*(x**2 - y**2) **2) + (x*y*sqrt((-x**2 + 1)*(y**2 - 1))*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*cos(z)/(y**2 - 1) + x*sqrt((-x**2 + 1)*(y**2 - 1))*(-x**2*y + y)*cos( z)/sqrt(-x**2*y**2 + x**2 + y**2 - 1))/(a*sqrt((-x**2 + 1)*(y**2 - 1) )*(x**2 - y**2)))*cos(z)/(a*sqrt((-x**2 + 1)*(y**2 - 1))*(x**2 - y**2) ) - x*sqrt((-x**2 + 1)*(y**2 - 1))*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*sin( z)**2/(a**2*(x**2 - 1)*(x**2 - y**2)*(y**2 - 1)) - x*sqrt((-x**2 + 1)*( y**2 - 1))*sqrt(-x**2*y**2 + x**2 + y**2 - 1)*cos(z)**2/(a**2*(x**2 - 1)*( x**2 - y**2)*(y**2 - 1)) assert simplify(expr) == 2*x/(a**2*(x**2 - y**2)) #issue 17631 assert simplify('((-1/2)*Boole(True)*Boole(False)-1)*Boole(True)') == \ Mul(sympify('(2 + Boole(True)*Boole(False))'), sympify('-Boole(True)/2')) A, B = symbols('A,B', commutative=False) assert simplify(A*B - B*A) == A*B - B*A assert simplify(A/(1 + y/x)) == x*A/(x + y) assert simplify(A*(1/x + 1/y)) == A/x + A/y #(x + y)*A/(x*y) assert simplify(log(2) + log(3)) == log(6) assert simplify(log(2*x) - log(2)) == log(x) assert simplify(hyper([], [], x)) == exp(x) def test_issue_3557(): f_1 = x*a + y*b + z*c - 1 f_2 = x*d + y*e + z*f - 1 f_3 = x*g + y*h + z*i - 1 solutions = solve([f_1, f_2, f_3], x, y, z, simplify=False) assert simplify(solutions[y]) == \ (a*i + c*d + f*g - a*f - c*g - d*i)/ \ (a*e*i + b*f*g + c*d*h - a*f*h - b*d*i - c*e*g) def test_simplify_other(): assert simplify(sin(x)**2 + cos(x)**2) == 1 assert simplify(gamma(x + 1)/gamma(x)) == x assert simplify(sin(x)**2 + cos(x)**2 + factorial(x)/gamma(x)) == 1 + x assert simplify( Eq(sin(x)**2 + cos(x)**2, factorial(x)/gamma(x))) == Eq(x, 1) nc = symbols('nc', commutative=False) assert simplify(x + x*nc) == x*(1 + nc) # issue 6123 # f = exp(-I*(k*sqrt(t) + x/(2*sqrt(t)))**2) # ans = integrate(f, (k, -oo, oo), conds='none') ans = I*(-pi*x*exp(I*pi*Rational(-3, 4) + I*x**2/(4*t))*erf(x*exp(I*pi*Rational(-3, 4))/ (2*sqrt(t)))/(2*sqrt(t)) + pi*x*exp(I*pi*Rational(-3, 4) + I*x**2/(4*t))/ (2*sqrt(t)))*exp(-I*x**2/(4*t))/(sqrt(pi)*x) - I*sqrt(pi) * \ (-erf(x*exp(I*pi/4)/(2*sqrt(t))) + 1)*exp(I*pi/4)/(2*sqrt(t)) assert simplify(ans) == -(-1)**Rational(3, 4)*sqrt(pi)/sqrt(t) # issue 6370 assert simplify(2**(2 + x)/4) == 2**x @_both_exp_pow def test_simplify_complex(): cosAsExp = cos(x)._eval_rewrite_as_exp(x) tanAsExp = tan(x)._eval_rewrite_as_exp(x) assert simplify(cosAsExp*tanAsExp) == sin(x) # issue 4341 # issue 10124 assert simplify(exp(Matrix([[0, -1], [1, 0]]))) == Matrix([[cos(1), -sin(1)], [sin(1), cos(1)]]) def test_simplify_ratio(): # roots of x**3-3*x+5 roots = ['(1/2 - sqrt(3)*I/2)*(sqrt(21)/2 + 5/2)**(1/3) + 1/((1/2 - ' 'sqrt(3)*I/2)*(sqrt(21)/2 + 5/2)**(1/3))', '1/((1/2 + sqrt(3)*I/2)*(sqrt(21)/2 + 5/2)**(1/3)) + ' '(1/2 + sqrt(3)*I/2)*(sqrt(21)/2 + 5/2)**(1/3)', '-(sqrt(21)/2 + 5/2)**(1/3) - 1/(sqrt(21)/2 + 5/2)**(1/3)'] for r in roots: r = S(r) assert count_ops(simplify(r, ratio=1)) <= count_ops(r) # If ratio=oo, simplify() is always applied: assert simplify(r, ratio=oo) is not r def test_simplify_measure(): measure1 = lambda expr: len(str(expr)) measure2 = lambda expr: -count_ops(expr) # Return the most complicated result expr = (x + 1)/(x + sin(x)**2 + cos(x)**2) assert measure1(simplify(expr, measure=measure1)) <= measure1(expr) assert measure2(simplify(expr, measure=measure2)) <= measure2(expr) expr2 = Eq(sin(x)**2 + cos(x)**2, 1) assert measure1(simplify(expr2, measure=measure1)) <= measure1(expr2) assert measure2(simplify(expr2, measure=measure2)) <= measure2(expr2) def test_simplify_rational(): expr = 2**x*2.**y assert simplify(expr, rational = True) == 2**(x+y) assert simplify(expr, rational = None) == 2.0**(x+y) assert simplify(expr, rational = False) == expr assert simplify('0.9 - 0.8 - 0.1', rational = True) == 0 def test_simplify_issue_1308(): assert simplify(exp(Rational(-1, 2)) + exp(Rational(-3, 2))) == \ (1 + E)*exp(Rational(-3, 2)) def test_issue_5652(): assert simplify(E + exp(-E)) == exp(-E) + E n = symbols('n', commutative=False) assert simplify(n + n**(-n)) == n + n**(-n) def test_simplify_fail1(): x = Symbol('x') y = Symbol('y') e = (x + y)**2/(-4*x*y**2 - 2*y**3 - 2*x**2*y) assert simplify(e) == 1 / (-2*y) def test_nthroot(): assert nthroot(90 + 34*sqrt(7), 3) == sqrt(7) + 3 q = 1 + sqrt(2) - 2*sqrt(3) + sqrt(6) + sqrt(7) assert nthroot(expand_multinomial(q**3), 3) == q assert nthroot(41 + 29*sqrt(2), 5) == 1 + sqrt(2) assert nthroot(-41 - 29*sqrt(2), 5) == -1 - sqrt(2) expr = 1320*sqrt(10) + 4216 + 2576*sqrt(6) + 1640*sqrt(15) assert nthroot(expr, 5) == 1 + sqrt(6) + sqrt(15) q = 1 + sqrt(2) + sqrt(3) + sqrt(5) assert expand_multinomial(nthroot(expand_multinomial(q**5), 5)) == q q = 1 + sqrt(2) + 7*sqrt(6) + 2*sqrt(10) assert nthroot(expand_multinomial(q**5), 5, 8) == q q = 1 + sqrt(2) - 2*sqrt(3) + 1171*sqrt(6) assert nthroot(expand_multinomial(q**3), 3) == q assert nthroot(expand_multinomial(q**6), 6) == q def test_nthroot1(): q = 1 + sqrt(2) + sqrt(3) + S.One/10**20 p = expand_multinomial(q**5) assert nthroot(p, 5) == q q = 1 + sqrt(2) + sqrt(3) + S.One/10**30 p = expand_multinomial(q**5) assert nthroot(p, 5) == q @_both_exp_pow def test_separatevars(): x, y, z, n = symbols('x,y,z,n') assert separatevars(2*n*x*z + 2*x*y*z) == 2*x*z*(n + y) assert separatevars(x*z + x*y*z) == x*z*(1 + y) assert separatevars(pi*x*z + pi*x*y*z) == pi*x*z*(1 + y) assert separatevars(x*y**2*sin(x) + x*sin(x)*sin(y)) == \ x*(sin(y) + y**2)*sin(x) assert separatevars(x*exp(x + y) + x*exp(x)) == x*(1 + exp(y))*exp(x) assert separatevars((x*(y + 1))**z).is_Pow # != x**z*(1 + y)**z assert separatevars(1 + x + y + x*y) == (x + 1)*(y + 1) assert separatevars(y/pi*exp(-(z - x)/cos(n))) == \ y*exp(x/cos(n))*exp(-z/cos(n))/pi assert separatevars((x + y)*(x - y) + y**2 + 2*x + 1) == (x + 1)**2 # issue 4858 p = Symbol('p', positive=True) assert separatevars(sqrt(p**2 + x*p**2)) == p*sqrt(1 + x) assert separatevars(sqrt(y*(p**2 + x*p**2))) == p*sqrt(y*(1 + x)) assert separatevars(sqrt(y*(p**2 + x*p**2)), force=True) == \ p*sqrt(y)*sqrt(1 + x) # issue 4865 assert separatevars(sqrt(x*y)).is_Pow assert separatevars(sqrt(x*y), force=True) == sqrt(x)*sqrt(y) # issue 4957 # any type sequence for symbols is fine assert separatevars(((2*x + 2)*y), dict=True, symbols=()) == \ {'coeff': 1, x: 2*x + 2, y: y} # separable assert separatevars(((2*x + 2)*y), dict=True, symbols=[x]) == \ {'coeff': y, x: 2*x + 2} assert separatevars(((2*x + 2)*y), dict=True, symbols=[]) == \ {'coeff': 1, x: 2*x + 2, y: y} assert separatevars(((2*x + 2)*y), dict=True) == \ {'coeff': 1, x: 2*x + 2, y: y} assert separatevars(((2*x + 2)*y), dict=True, symbols=None) == \ {'coeff': y*(2*x + 2)} # not separable assert separatevars(3, dict=True) is None assert separatevars(2*x + y, dict=True, symbols=()) is None assert separatevars(2*x + y, dict=True) is None assert separatevars(2*x + y, dict=True, symbols=None) == {'coeff': 2*x + y} # issue 4808 n, m = symbols('n,m', commutative=False) assert separatevars(m + n*m) == (1 + n)*m assert separatevars(x + x*n) == x*(1 + n) # issue 4910 f = Function('f') assert separatevars(f(x) + x*f(x)) == f(x) + x*f(x) # a noncommutable object present eq = x*(1 + hyper((), (), y*z)) assert separatevars(eq) == eq s = separatevars(abs(x*y)) assert s == abs(x)*abs(y) and s.is_Mul z = cos(1)**2 + sin(1)**2 - 1 a = abs(x*z) s = separatevars(a) assert not a.is_Mul and s.is_Mul and s == abs(x)*abs(z) s = separatevars(abs(x*y*z)) assert s == abs(x)*abs(y)*abs(z) # abs(x+y)/abs(z) would be better but we test this here to # see that it doesn't raise assert separatevars(abs((x+y)/z)) == abs((x+y)/z) def test_separatevars_advanced_factor(): x, y, z = symbols('x,y,z') assert separatevars(1 + log(x)*log(y) + log(x) + log(y)) == \ (log(x) + 1)*(log(y) + 1) assert separatevars(1 + x - log(z) - x*log(z) - exp(y)*log(z) - x*exp(y)*log(z) + x*exp(y) + exp(y)) == \ -((x + 1)*(log(z) - 1)*(exp(y) + 1)) x, y = symbols('x,y', positive=True) assert separatevars(1 + log(x**log(y)) + log(x*y)) == \ (log(x) + 1)*(log(y) + 1) def test_hypersimp(): n, k = symbols('n,k', integer=True) assert hypersimp(factorial(k), k) == k + 1 assert hypersimp(factorial(k**2), k) is None assert hypersimp(1/factorial(k), k) == 1/(k + 1) assert hypersimp(2**k/factorial(k)**2, k) == 2/(k + 1)**2 assert hypersimp(binomial(n, k), k) == (n - k)/(k + 1) assert hypersimp(binomial(n + 1, k), k) == (n - k + 1)/(k + 1) term = (4*k + 1)*factorial(k)/factorial(2*k + 1) assert hypersimp(term, k) == S.Half*((4*k + 5)/(3 + 14*k + 8*k**2)) term = 1/((2*k - 1)*factorial(2*k + 1)) assert hypersimp(term, k) == (k - S.Half)/((k + 1)*(2*k + 1)*(2*k + 3)) term = binomial(n, k)*(-1)**k/factorial(k) assert hypersimp(term, k) == (k - n)/(k + 1)**2 def test_nsimplify(): x = Symbol("x") assert nsimplify(0) == 0 assert nsimplify(-1) == -1 assert nsimplify(1) == 1 assert nsimplify(1 + x) == 1 + x assert nsimplify(2.7) == Rational(27, 10) assert nsimplify(1 - GoldenRatio) == (1 - sqrt(5))/2 assert nsimplify((1 + sqrt(5))/4, [GoldenRatio]) == GoldenRatio/2 assert nsimplify(2/GoldenRatio, [GoldenRatio]) == 2*GoldenRatio - 2 assert nsimplify(exp(pi*I*Rational(5, 3), evaluate=False)) == \ sympify('1/2 - sqrt(3)*I/2') assert nsimplify(sin(pi*Rational(3, 5), evaluate=False)) == \ sympify('sqrt(sqrt(5)/8 + 5/8)') assert nsimplify(sqrt(atan('1', evaluate=False))*(2 + I), [pi]) == \ sqrt(pi) + sqrt(pi)/2*I assert nsimplify(2 + exp(2*atan('1/4')*I)) == sympify('49/17 + 8*I/17') assert nsimplify(pi, tolerance=0.01) == Rational(22, 7) assert nsimplify(pi, tolerance=0.001) == Rational(355, 113) assert nsimplify(0.33333, tolerance=1e-4) == Rational(1, 3) assert nsimplify(2.0**(1/3.), tolerance=0.001) == Rational(635, 504) assert nsimplify(2.0**(1/3.), tolerance=0.001, full=True) == \ 2**Rational(1, 3) assert nsimplify(x + .5, rational=True) == S.Half + x assert nsimplify(1/.3 + x, rational=True) == Rational(10, 3) + x assert nsimplify(log(3).n(), rational=True) == \ sympify('109861228866811/100000000000000') assert nsimplify(Float(0.272198261287950), [pi, log(2)]) == pi*log(2)/8 assert nsimplify(Float(0.272198261287950).n(3), [pi, log(2)]) == \ -pi/4 - log(2) + Rational(7, 4) assert nsimplify(x/7.0) == x/7 assert nsimplify(pi/1e2) == pi/100 assert nsimplify(pi/1e2, rational=False) == pi/100.0 assert nsimplify(pi/1e-7) == 10000000*pi assert not nsimplify( factor(-3.0*z**2*(z**2)**(-2.5) + 3*(z**2)**(-1.5))).atoms(Float) e = x**0.0 assert e.is_Pow and nsimplify(x**0.0) == 1 assert nsimplify(3.333333, tolerance=0.1, rational=True) == Rational(10, 3) assert nsimplify(3.333333, tolerance=0.01, rational=True) == Rational(10, 3) assert nsimplify(3.666666, tolerance=0.1, rational=True) == Rational(11, 3) assert nsimplify(3.666666, tolerance=0.01, rational=True) == Rational(11, 3) assert nsimplify(33, tolerance=10, rational=True) == Rational(33) assert nsimplify(33.33, tolerance=10, rational=True) == Rational(30) assert nsimplify(37.76, tolerance=10, rational=True) == Rational(40) assert nsimplify(-203.1) == Rational(-2031, 10) assert nsimplify(.2, tolerance=0) == Rational(1, 5) assert nsimplify(-.2, tolerance=0) == Rational(-1, 5) assert nsimplify(.2222, tolerance=0) == Rational(1111, 5000) assert nsimplify(-.2222, tolerance=0) == Rational(-1111, 5000) # issue 7211, PR 4112 assert nsimplify(S(2e-8)) == Rational(1, 50000000) # issue 7322 direct test assert nsimplify(1e-42, rational=True) != 0 # issue 10336 inf = Float('inf') infs = (-oo, oo, inf, -inf) for zi in infs: ans = sign(zi)*oo assert nsimplify(zi) == ans assert nsimplify(zi + x) == x + ans assert nsimplify(0.33333333, rational=True, rational_conversion='exact') == Rational(0.33333333) # Make sure nsimplify on expressions uses full precision assert nsimplify(pi.evalf(100)*x, rational_conversion='exact').evalf(100) == pi.evalf(100)*x def test_issue_9448(): tmp = sympify("1/(1 - (-1)**(2/3) - (-1)**(1/3)) + 1/(1 + (-1)**(2/3) + (-1)**(1/3))") assert nsimplify(tmp) == S.Half def test_extract_minus_sign(): x = Symbol("x") y = Symbol("y") a = Symbol("a") b = Symbol("b") assert simplify(-x/-y) == x/y assert simplify(-x/y) == -x/y assert simplify(x/y) == x/y assert simplify(x/-y) == -x/y assert simplify(-x/0) == zoo*x assert simplify(Rational(-5, 0)) is zoo assert simplify(-a*x/(-y - b)) == a*x/(b + y) def test_diff(): x = Symbol("x") y = Symbol("y") f = Function("f") g = Function("g") assert simplify(g(x).diff(x)*f(x).diff(x) - f(x).diff(x)*g(x).diff(x)) == 0 assert simplify(2*f(x)*f(x).diff(x) - diff(f(x)**2, x)) == 0 assert simplify(diff(1/f(x), x) + f(x).diff(x)/f(x)**2) == 0 assert simplify(f(x).diff(x, y) - f(x).diff(y, x)) == 0 def test_logcombine_1(): x, y = symbols("x,y") a = Symbol("a") z, w = symbols("z,w", positive=True) b = Symbol("b", real=True) assert logcombine(log(x) + 2*log(y)) == log(x) + 2*log(y) assert logcombine(log(x) + 2*log(y), force=True) == log(x*y**2) assert logcombine(a*log(w) + log(z)) == a*log(w) + log(z) assert logcombine(b*log(z) + b*log(x)) == log(z**b) + b*log(x) assert logcombine(b*log(z) - log(w)) == log(z**b/w) assert logcombine(log(x)*log(z)) == log(x)*log(z) assert logcombine(log(w)*log(x)) == log(w)*log(x) assert logcombine(cos(-2*log(z) + b*log(w))) in [cos(log(w**b/z**2)), cos(log(z**2/w**b))] assert logcombine(log(log(x) - log(y)) - log(z), force=True) == \ log(log(x/y)/z) assert logcombine((2 + I)*log(x), force=True) == (2 + I)*log(x) assert logcombine((x**2 + log(x) - log(y))/(x*y), force=True) == \ (x**2 + log(x/y))/(x*y) # the following could also give log(z*x**log(y**2)), what we # are testing is that a canonical result is obtained assert logcombine(log(x)*2*log(y) + log(z), force=True) == \ log(z*y**log(x**2)) assert logcombine((x*y + sqrt(x**4 + y**4) + log(x) - log(y))/(pi*x**Rational(2, 3)* sqrt(y)**3), force=True) == ( x*y + sqrt(x**4 + y**4) + log(x/y))/(pi*x**Rational(2, 3)*y**Rational(3, 2)) assert logcombine(gamma(-log(x/y))*acos(-log(x/y)), force=True) == \ acos(-log(x/y))*gamma(-log(x/y)) assert logcombine(2*log(z)*log(w)*log(x) + log(z) + log(w)) == \ log(z**log(w**2))*log(x) + log(w*z) assert logcombine(3*log(w) + 3*log(z)) == log(w**3*z**3) assert logcombine(x*(y + 1) + log(2) + log(3)) == x*(y + 1) + log(6) assert logcombine((x + y)*log(w) + (-x - y)*log(3)) == (x + y)*log(w/3) # a single unknown can combine assert logcombine(log(x) + log(2)) == log(2*x) eq = log(abs(x)) + log(abs(y)) assert logcombine(eq) == eq reps = {x: 0, y: 0} assert log(abs(x)*abs(y)).subs(reps) != eq.subs(reps) def test_logcombine_complex_coeff(): i = Integral((sin(x**2) + cos(x**3))/x, x) assert logcombine(i, force=True) == i assert logcombine(i + 2*log(x), force=True) == \ i + log(x**2) def test_issue_5950(): x, y = symbols("x,y", positive=True) assert logcombine(log(3) - log(2)) == log(Rational(3,2), evaluate=False) assert logcombine(log(x) - log(y)) == log(x/y) assert logcombine(log(Rational(3,2), evaluate=False) - log(2)) == \ log(Rational(3,4), evaluate=False) def test_posify(): from sympy.abc import x assert str(posify( x + Symbol('p', positive=True) + Symbol('n', negative=True))) == '(_x + n + p, {_x: x})' eq, rep = posify(1/x) assert log(eq).expand().subs(rep) == -log(x) assert str(posify([x, 1 + x])) == '([_x, _x + 1], {_x: x})' x = symbols('x') p = symbols('p', positive=True) n = symbols('n', negative=True) orig = [x, n, p] modified, reps = posify(orig) assert str(modified) == '[_x, n, p]' assert [w.subs(reps) for w in modified] == orig assert str(Integral(posify(1/x + y)[0], (y, 1, 3)).expand()) == \ 'Integral(1/_x, (y, 1, 3)) + Integral(_y, (y, 1, 3))' assert str(Sum(posify(1/x**n)[0], (n,1,3)).expand()) == \ 'Sum(_x**(-n), (n, 1, 3))' # issue 16438 k = Symbol('k', finite=True) eq, rep = posify(k) assert eq.assumptions0 == {'positive': True, 'zero': False, 'imaginary': False, 'nonpositive': False, 'commutative': True, 'hermitian': True, 'real': True, 'nonzero': True, 'nonnegative': True, 'negative': False, 'complex': True, 'finite': True, 'infinite': False, 'extended_real':True, 'extended_negative': False, 'extended_nonnegative': True, 'extended_nonpositive': False, 'extended_nonzero': True, 'extended_positive': True} def test_issue_4194(): # simplify should call cancel from sympy.abc import x, y f = Function('f') assert simplify((4*x + 6*f(y))/(2*x + 3*f(y))) == 2 @XFAIL def test_simplify_float_vs_integer(): # Test for issue 4473: # https://github.com/sympy/sympy/issues/4473 assert simplify(x**2.0 - x**2) == 0 assert simplify(x**2 - x**2.0) == 0 def test_as_content_primitive(): assert (x/2 + y).as_content_primitive() == (S.Half, x + 2*y) assert (x/2 + y).as_content_primitive(clear=False) == (S.One, x/2 + y) assert (y*(x/2 + y)).as_content_primitive() == (S.Half, y*(x + 2*y)) assert (y*(x/2 + y)).as_content_primitive(clear=False) == (S.One, y*(x/2 + y)) # although the _as_content_primitive methods do not alter the underlying structure, # the as_content_primitive function will touch up the expression and join # bases that would otherwise have not been joined. assert (x*(2 + 2*x)*(3*x + 3)**2).as_content_primitive() == \ (18, x*(x + 1)**3) assert (2 + 2*x + 2*y*(3 + 3*y)).as_content_primitive() == \ (2, x + 3*y*(y + 1) + 1) assert ((2 + 6*x)**2).as_content_primitive() == \ (4, (3*x + 1)**2) assert ((2 + 6*x)**(2*y)).as_content_primitive() == \ (1, (_keep_coeff(S(2), (3*x + 1)))**(2*y)) assert (5 + 10*x + 2*y*(3 + 3*y)).as_content_primitive() == \ (1, 10*x + 6*y*(y + 1) + 5) assert (5*(x*(1 + y)) + 2*x*(3 + 3*y)).as_content_primitive() == \ (11, x*(y + 1)) assert ((5*(x*(1 + y)) + 2*x*(3 + 3*y))**2).as_content_primitive() == \ (121, x**2*(y + 1)**2) assert (y**2).as_content_primitive() == \ (1, y**2) assert (S.Infinity).as_content_primitive() == (1, oo) eq = x**(2 + y) assert (eq).as_content_primitive() == (1, eq) assert (S.Half**(2 + x)).as_content_primitive() == (Rational(1, 4), 2**-x) assert (Rational(-1, 2)**(2 + x)).as_content_primitive() == \ (Rational(1, 4), (Rational(-1, 2))**x) assert (Rational(-1, 2)**(2 + x)).as_content_primitive() == \ (Rational(1, 4), Rational(-1, 2)**x) assert (4**((1 + y)/2)).as_content_primitive() == (2, 4**(y/2)) assert (3**((1 + y)/2)).as_content_primitive() == \ (1, 3**(Mul(S.Half, 1 + y, evaluate=False))) assert (5**Rational(3, 4)).as_content_primitive() == (1, 5**Rational(3, 4)) assert (5**Rational(7, 4)).as_content_primitive() == (5, 5**Rational(3, 4)) assert Add(z*Rational(5, 7), 0.5*x, y*Rational(3, 2), evaluate=False).as_content_primitive() == \ (Rational(1, 14), 7.0*x + 21*y + 10*z) assert (2**Rational(3, 4) + 2**Rational(1, 4)*sqrt(3)).as_content_primitive(radical=True) == \ (1, 2**Rational(1, 4)*(sqrt(2) + sqrt(3))) def test_signsimp(): e = x*(-x + 1) + x*(x - 1) assert signsimp(Eq(e, 0)) is S.true assert Abs(x - 1) == Abs(1 - x) assert signsimp(y - x) == y - x assert signsimp(y - x, evaluate=False) == Mul(-1, x - y, evaluate=False) def test_besselsimp(): from sympy import besselj, besseli, cosh, cosine_transform, bessely assert besselsimp(exp(-I*pi*y/2)*besseli(y, z*exp_polar(I*pi/2))) == \ besselj(y, z) assert besselsimp(exp(-I*pi*a/2)*besseli(a, 2*sqrt(x)*exp_polar(I*pi/2))) == \ besselj(a, 2*sqrt(x)) assert besselsimp(sqrt(2)*sqrt(pi)*x**Rational(1, 4)*exp(I*pi/4)*exp(-I*pi*a/2) * besseli(Rational(-1, 2), sqrt(x)*exp_polar(I*pi/2)) * besseli(a, sqrt(x)*exp_polar(I*pi/2))/2) == \ besselj(a, sqrt(x)) * cos(sqrt(x)) assert besselsimp(besseli(Rational(-1, 2), z)) == \ sqrt(2)*cosh(z)/(sqrt(pi)*sqrt(z)) assert besselsimp(besseli(a, z*exp_polar(-I*pi/2))) == \ exp(-I*pi*a/2)*besselj(a, z) assert cosine_transform(1/t*sin(a/t), t, y) == \ sqrt(2)*sqrt(pi)*besselj(0, 2*sqrt(a)*sqrt(y))/2 assert besselsimp(x**2*(a*(-2*besselj(5*I, x) + besselj(-2 + 5*I, x) + besselj(2 + 5*I, x)) + b*(-2*bessely(5*I, x) + bessely(-2 + 5*I, x) + bessely(2 + 5*I, x)))/4 + x*(a*(besselj(-1 + 5*I, x)/2 - besselj(1 + 5*I, x)/2) + b*(bessely(-1 + 5*I, x)/2 - bessely(1 + 5*I, x)/2)) + (x**2 + 25)*(a*besselj(5*I, x) + b*bessely(5*I, x))) == 0 assert besselsimp(81*x**2*(a*(besselj(Rational(-5, 3), 9*x) - 2*besselj(Rational(1, 3), 9*x) + besselj(Rational(7, 3), 9*x)) + b*(bessely(Rational(-5, 3), 9*x) - 2*bessely(Rational(1, 3), 9*x) + bessely(Rational(7, 3), 9*x)))/4 + x*(a*(9*besselj(Rational(-2, 3), 9*x)/2 - 9*besselj(Rational(4, 3), 9*x)/2) + b*(9*bessely(Rational(-2, 3), 9*x)/2 - 9*bessely(Rational(4, 3), 9*x)/2)) + (81*x**2 - Rational(1, 9))*(a*besselj(Rational(1, 3), 9*x) + b*bessely(Rational(1, 3), 9*x))) == 0 assert besselsimp(besselj(a-1,x) + besselj(a+1, x) - 2*a*besselj(a, x)/x) == 0 assert besselsimp(besselj(a-1,x) + besselj(a+1, x) + besselj(a, x)) == (2*a + x)*besselj(a, x)/x assert besselsimp(x**2* besselj(a,x) + x**3*besselj(a+1, x) + besselj(a+2, x)) == \ 2*a*x*besselj(a + 1, x) + x**3*besselj(a + 1, x) - x**2*besselj(a + 2, x) + 2*x*besselj(a + 1, x) + besselj(a + 2, x) def test_Piecewise(): e1 = x*(x + y) - y*(x + y) e2 = sin(x)**2 + cos(x)**2 e3 = expand((x + y)*y/x) s1 = simplify(e1) s2 = simplify(e2) s3 = simplify(e3) assert simplify(Piecewise((e1, x < e2), (e3, True))) == \ Piecewise((s1, x < s2), (s3, True)) def test_polymorphism(): class A(Basic): def _eval_simplify(x, **kwargs): return S.One a = A(5, 2) assert simplify(a) == 1 def test_issue_from_PR1599(): n1, n2, n3, n4 = symbols('n1 n2 n3 n4', negative=True) assert simplify(I*sqrt(n1)) == -sqrt(-n1) def test_issue_6811(): eq = (x + 2*y)*(2*x + 2) assert simplify(eq) == (x + 1)*(x + 2*y)*2 # reject the 2-arg Mul -- these are a headache for test writing assert simplify(eq.expand()) == \ 2*x**2 + 4*x*y + 2*x + 4*y def test_issue_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_issue_7001(): from sympy.abc import r, R assert simplify(-(r*Piecewise((pi*Rational(4, 3), r <= R), (-8*pi*R**3/(3*r**3), True)) + 2*Piecewise((pi*r*Rational(4, 3), r <= R), (4*pi*R**3/(3*r**2), True)))/(4*pi*r)) == \ Piecewise((-1, r <= R), (0, True)) def test_inequality_no_auto_simplify(): # no simplify on creation but can be simplified lhs = cos(x)**2 + sin(x)**2 rhs = 2 e = Lt(lhs, rhs, evaluate=False) assert e is not S.true assert simplify(e) def test_issue_9398(): from sympy import Number, cancel assert cancel(1e-14) != 0 assert cancel(1e-14*I) != 0 assert simplify(1e-14) != 0 assert simplify(1e-14*I) != 0 assert (I*Number(1.)*Number(10)**Number(-14)).simplify() != 0 assert cancel(1e-20) != 0 assert cancel(1e-20*I) != 0 assert simplify(1e-20) != 0 assert simplify(1e-20*I) != 0 assert cancel(1e-100) != 0 assert cancel(1e-100*I) != 0 assert simplify(1e-100) != 0 assert simplify(1e-100*I) != 0 f = Float("1e-1000") assert cancel(f) != 0 assert cancel(f*I) != 0 assert simplify(f) != 0 assert simplify(f*I) != 0 def test_issue_9324_simplify(): M = MatrixSymbol('M', 10, 10) e = M[0, 0] + M[5, 4] + 1304 assert simplify(e) == e def test_issue_9817_simplify(): # simplify on trace of substituted explicit quadratic form of matrix # expressions (a scalar) should return without errors (AttributeError) # See issue #9817 and #9190 for the original bug more discussion on this from sympy.matrices.expressions import Identity, trace v = MatrixSymbol('v', 3, 1) A = MatrixSymbol('A', 3, 3) x = Matrix([i + 1 for i in range(3)]) X = Identity(3) quadratic = v.T * A * v assert simplify((trace(quadratic.as_explicit())).xreplace({v:x, A:X})) == 14 def test_issue_13474(): x = Symbol('x') assert simplify(x + csch(sinc(1))) == x + csch(sinc(1)) @_both_exp_pow def test_simplify_function_inverse(): # "inverse" attribute does not guarantee that f(g(x)) is x # so this simplification should not happen automatically. # See issue #12140 x, y = symbols('x, y') g = Function('g') class f(Function): def inverse(self, argindex=1): return g assert simplify(f(g(x))) == f(g(x)) assert inversecombine(f(g(x))) == x assert simplify(f(g(x)), inverse=True) == x assert simplify(f(g(sin(x)**2 + cos(x)**2)), inverse=True) == 1 assert simplify(f(g(x, y)), inverse=True) == f(g(x, y)) assert unchanged(asin, sin(x)) assert simplify(asin(sin(x))) == asin(sin(x)) assert simplify(2*asin(sin(3*x)), inverse=True) == 6*x assert simplify(log(exp(x))) == log(exp(x)) assert simplify(log(exp(x)), inverse=True) == x assert simplify(exp(log(x)), inverse=True) == x assert simplify(log(exp(x), 2), inverse=True) == x/log(2) assert simplify(log(exp(x), 2, evaluate=False), inverse=True) == x/log(2) def test_clear_coefficients(): from sympy.simplify.simplify import clear_coefficients assert clear_coefficients(4*y*(6*x + 3)) == (y*(2*x + 1), 0) assert clear_coefficients(4*y*(6*x + 3) - 2) == (y*(2*x + 1), Rational(1, 6)) assert clear_coefficients(4*y*(6*x + 3) - 2, x) == (y*(2*x + 1), x/12 + Rational(1, 6)) assert clear_coefficients(sqrt(2) - 2) == (sqrt(2), 2) assert clear_coefficients(4*sqrt(2) - 2) == (sqrt(2), S.Half) assert clear_coefficients(S(3), x) == (0, x - 3) assert clear_coefficients(S.Infinity, x) == (S.Infinity, x) assert clear_coefficients(-S.Pi, x) == (S.Pi, -x) assert clear_coefficients(2 - S.Pi/3, x) == (pi, -3*x + 6) def test_nc_simplify(): from sympy.simplify.simplify import nc_simplify from sympy.matrices.expressions import MatPow, Identity from sympy.core import Pow from functools import reduce a, b, c, d = symbols('a b c d', commutative = False) x = Symbol('x') A = MatrixSymbol("A", x, x) B = MatrixSymbol("B", x, x) C = MatrixSymbol("C", x, x) D = MatrixSymbol("D", x, x) subst = {a: A, b: B, c: C, d:D} funcs = {Add: lambda x,y: x+y, Mul: lambda x,y: x*y } def _to_matrix(expr): if expr in subst: return subst[expr] if isinstance(expr, Pow): return MatPow(_to_matrix(expr.args[0]), expr.args[1]) elif isinstance(expr, (Add, Mul)): return reduce(funcs[expr.func],[_to_matrix(a) for a in expr.args]) else: return expr*Identity(x) def _check(expr, simplified, deep=True, matrix=True): assert nc_simplify(expr, deep=deep) == simplified assert expand(expr) == expand(simplified) if matrix: m_simp = _to_matrix(simplified).doit(inv_expand=False) assert nc_simplify(_to_matrix(expr), deep=deep) == m_simp _check(a*b*a*b*a*b*c*(a*b)**3*c, ((a*b)**3*c)**2) _check(a*b*(a*b)**-2*a*b, 1) _check(a**2*b*a*b*a*b*(a*b)**-1, a*(a*b)**2, matrix=False) _check(b*a*b**2*a*b**2*a*b**2, b*(a*b**2)**3) _check(a*b*a**2*b*a**2*b*a**3, (a*b*a)**3*a**2) _check(a**2*b*a**4*b*a**4*b*a**2, (a**2*b*a**2)**3) _check(a**3*b*a**4*b*a**4*b*a, a**3*(b*a**4)**3*a**-3) _check(a*b*a*b + a*b*c*x*a*b*c, (a*b)**2 + x*(a*b*c)**2) _check(a*b*a*b*c*a*b*a*b*c, ((a*b)**2*c)**2) _check(b**-1*a**-1*(a*b)**2, a*b) _check(a**-1*b*c**-1, (c*b**-1*a)**-1) expr = a**3*b*a**4*b*a**4*b*a**2*b*a**2*(b*a**2)**2*b*a**2*b*a**2 for _ in range(10): expr *= a*b _check(expr, a**3*(b*a**4)**2*(b*a**2)**6*(a*b)**10) _check((a*b*a*b)**2, (a*b*a*b)**2, deep=False) _check(a*b*(c*d)**2, a*b*(c*d)**2) expr = b**-1*(a**-1*b**-1 - a**-1*c*b**-1)**-1*a**-1 assert nc_simplify(expr) == (1-c)**-1 # commutative expressions should be returned without an error assert nc_simplify(2*x**2) == 2*x**2 def test_issue_15965(): A = Sum(z*x**y, (x, 1, a)) anew = z*Sum(x**y, (x, 1, a)) B = Integral(x*y, x) bdo = x**2*y/2 assert simplify(A + B) == anew + bdo assert simplify(A) == anew assert simplify(B) == bdo assert simplify(B, doit=False) == y*Integral(x, x) def test_issue_17137(): assert simplify(cos(x)**I) == cos(x)**I assert simplify(cos(x)**(2 + 3*I)) == cos(x)**(2 + 3*I) def test_issue_21869(): x = Symbol('x', real=True) y = Symbol('y', real=True) expr = And(Eq(x**2, 4), Le(x, y)) assert expr.simplify() == expr expr = And(Eq(x**2, 4), Eq(x, 2)) assert expr.simplify() == Eq(x, 2) expr = And(Eq(x**3, x**2), Eq(x, 1)) assert expr.simplify() == Eq(x, 1) expr = And(Eq(sin(x), x**2), Eq(x, 0)) assert expr.simplify() == Eq(x, 0) expr = And(Eq(x**3, x**2), Eq(x, 2)) assert expr.simplify() == S.false expr = And(Eq(y, x**2), Eq(x, 1)) assert expr.simplify() == And(Eq(y,1), Eq(x, 1)) expr = And(Eq(y**2, 1), Eq(y, x**2), Eq(x, 1)) assert expr.simplify() == And(Eq(y,1), Eq(x, 1)) expr = And(Eq(y**2, 4), Eq(y, 2*x**2), Eq(x, 1)) assert expr.simplify() == And(Eq(y,2), Eq(x, 1)) expr = And(Eq(y**2, 4), Eq(y, x**2), Eq(x, 1)) assert expr.simplify() == S.false def test_issue_7971(): z = Integral(x, (x, 1, 1)) assert z != 0 assert simplify(z) is S.Zero @slow def test_issue_17141_slow(): # Should not give RecursionError assert simplify((2**acos(I+1)**2).rewrite('log')) == 2**((pi + 2*I*log(-1 + sqrt(1 - 2*I) + I))**2/4) def test_issue_17141(): # Check that there is no RecursionError assert simplify(x**(1 / acos(I))) == x**(2/(pi - 2*I*log(1 + sqrt(2)))) assert simplify(acos(-I)**2*acos(I)**2) == \ log(1 + sqrt(2))**4 + pi**2*log(1 + sqrt(2))**2/2 + pi**4/16 assert simplify(2**acos(I)**2) == 2**((pi - 2*I*log(1 + sqrt(2)))**2/4) p = 2**acos(I+1)**2 assert simplify(p) == p def test_simplify_kroneckerdelta(): i, j = symbols("i j") K = KroneckerDelta assert simplify(K(i, j)) == K(i, j) assert simplify(K(0, j)) == K(0, j) assert simplify(K(i, 0)) == K(i, 0) assert simplify(K(0, j).rewrite(Piecewise) * K(1, j)) == 0 assert simplify(K(1, i) + Piecewise((1, Eq(j, 2)), (0, True))) == K(1, i) + K(2, j) # issue 17214 assert simplify(K(0, j) * K(1, j)) == 0 n = Symbol('n', integer=True) assert simplify(K(0, n) * K(1, n)) == 0 M = Matrix(4, 4, lambda i, j: K(j - i, n) if i <= j else 0) assert simplify(M**2) == Matrix([[K(0, n), 0, K(1, n), 0], [0, K(0, n), 0, K(1, n)], [0, 0, K(0, n), 0], [0, 0, 0, K(0, n)]]) def test_issue_17292(): assert simplify(abs(x)/abs(x**2)) == 1/abs(x) # this is bigger than the issue: check that deep processing works assert simplify(5*abs((x**2 - 1)/(x - 1))) == 5*Abs(x + 1) def test_issue_19822(): expr = And(Gt(n-2, 1), Gt(n, 1)) assert simplify(expr) == Gt(n, 3) def test_issue_18645(): expr = And(Ge(x, 3), Le(x, 3)) assert simplify(expr) == Eq(x, 3) expr = And(Eq(x, 3), Le(x, 3)) assert simplify(expr) == Eq(x, 3) @XFAIL def test_issue_18642(): i = Symbol("i", integer=True) n = Symbol("n", integer=True) expr = And(Eq(i, 2 * n), Le(i, 2*n -1)) assert simplify(expr) == S.false @XFAIL def test_issue_18389(): n = Symbol("n", integer=True) expr = Eq(n, 0) | (n >= 1) assert simplify(expr) == Ge(n, 0) def test_issue_8373(): x = Symbol('x', real=True) assert simplify(Or(x < 1, x >= 1)) == S.true def test_issue_7950(): expr = And(Eq(x, 1), Eq(x, 2)) assert simplify(expr) == S.false def test_issue_19484(): assert simplify(sign(x) * Abs(x)) == x e = x + sign(x + x**3) assert simplify(Abs(x + x**3)*e) == x**3 + x*Abs(x**3 + x) + x e = x**2 + sign(x**3 + 1) assert simplify(Abs(x**3 + 1) * e) == x**3 + x**2*Abs(x**3 + 1) + 1 f = Function('f') e = x + sign(x + f(x)**3) assert simplify(Abs(x + f(x)**3) * e) == x*Abs(x + f(x)**3) + x + f(x)**3 def test_issue_19161(): polynomial = Poly('x**2').simplify() assert (polynomial-x**2).simplify() == 0