"""Tests for tools for manipulating of large commutative expressions. """ from sympy.concrete.summations import Sum from sympy.core.add import Add from sympy.core.basic import Basic from sympy.core.containers import (Dict, Tuple) from sympy.core.function import Function from sympy.core.mul import Mul from sympy.core.numbers import (I, Rational, oo) from sympy.core.singleton import S from sympy.core.symbol import (Dummy, Symbol, symbols) from sympy.functions.elementary.exponential import (exp, log) from sympy.functions.elementary.miscellaneous import (root, sqrt) from sympy.functions.elementary.trigonometric import (cos, sin) from sympy.integrals.integrals import Integral from sympy.series.order import O from sympy.sets.sets import Interval from sympy.simplify.radsimp import collect from sympy.simplify.simplify import simplify from sympy.core.exprtools import (decompose_power, Factors, Term, _gcd_terms, gcd_terms, factor_terms, factor_nc, _mask_nc, _monotonic_sign) from sympy.core.mul import _keep_coeff as _keep_coeff from sympy.simplify.cse_opts import sub_pre from sympy.testing.pytest import raises from sympy.abc import a, b, t, x, y, z def test_decompose_power(): assert decompose_power(x) == (x, 1) assert decompose_power(x**2) == (x, 2) assert decompose_power(x**(2*y)) == (x**y, 2) assert decompose_power(x**(2*y/3)) == (x**(y/3), 2) assert decompose_power(x**(y*Rational(2, 3))) == (x**(y/3), 2) def test_Factors(): assert Factors() == Factors({}) == Factors(S.One) assert Factors().as_expr() is S.One assert Factors({x: 2, y: 3, sin(x): 4}).as_expr() == x**2*y**3*sin(x)**4 assert Factors(S.Infinity) == Factors({oo: 1}) assert Factors(S.NegativeInfinity) == Factors({oo: 1, -1: 1}) # issue #18059: assert Factors((x**2)**S.Half).as_expr() == (x**2)**S.Half a = Factors({x: 5, y: 3, z: 7}) b = Factors({ y: 4, z: 3, t: 10}) assert a.mul(b) == a*b == Factors({x: 5, y: 7, z: 10, t: 10}) assert a.div(b) == divmod(a, b) == \ (Factors({x: 5, z: 4}), Factors({y: 1, t: 10})) assert a.quo(b) == a/b == Factors({x: 5, z: 4}) assert a.rem(b) == a % b == Factors({y: 1, t: 10}) assert a.pow(3) == a**3 == Factors({x: 15, y: 9, z: 21}) assert b.pow(3) == b**3 == Factors({y: 12, z: 9, t: 30}) assert a.gcd(b) == Factors({y: 3, z: 3}) assert a.lcm(b) == Factors({x: 5, y: 4, z: 7, t: 10}) a = Factors({x: 4, y: 7, t: 7}) b = Factors({z: 1, t: 3}) assert a.normal(b) == (Factors({x: 4, y: 7, t: 4}), Factors({z: 1})) assert Factors(sqrt(2)*x).as_expr() == sqrt(2)*x assert Factors(-I)*I == Factors() assert Factors({S.NegativeOne: S(3)})*Factors({S.NegativeOne: S.One, I: S(5)}) == \ Factors(I) assert Factors(sqrt(I)*I) == Factors(I**(S(3)/2)) == Factors({I: S(3)/2}) assert Factors({I: S(3)/2}).as_expr() == I**(S(3)/2) assert Factors(S(2)**x).div(S(3)**x) == \ (Factors({S(2): x}), Factors({S(3): x})) assert Factors(2**(2*x + 2)).div(S(8)) == \ (Factors({S(2): 2*x + 2}), Factors({S(8): S.One})) # coverage # /!\ things break if this is not True assert Factors({S.NegativeOne: Rational(3, 2)}) == Factors({I: S.One, S.NegativeOne: S.One}) assert Factors({I: S.One, S.NegativeOne: Rational(1, 3)}).as_expr() == I*(-1)**Rational(1, 3) assert Factors(-1.) == Factors({S.NegativeOne: S.One, S(1.): 1}) assert Factors(-2.) == Factors({S.NegativeOne: S.One, S(2.): 1}) assert Factors((-2.)**x) == Factors({S(-2.): x}) assert Factors(S(-2)) == Factors({S.NegativeOne: S.One, S(2): 1}) assert Factors(S.Half) == Factors({S(2): -S.One}) assert Factors(Rational(3, 2)) == Factors({S(3): S.One, S(2): S.NegativeOne}) assert Factors({I: S.One}) == Factors(I) assert Factors({-1.0: 2, I: 1}) == Factors({S(1.0): 1, I: 1}) assert Factors({S.NegativeOne: Rational(-3, 2)}).as_expr() == I A = symbols('A', commutative=False) assert Factors(2*A**2) == Factors({S(2): 1, A**2: 1}) assert Factors(I) == Factors({I: S.One}) assert Factors(x).normal(S(2)) == (Factors(x), Factors(S(2))) assert Factors(x).normal(S.Zero) == (Factors(), Factors(S.Zero)) raises(ZeroDivisionError, lambda: Factors(x).div(S.Zero)) assert Factors(x).mul(S(2)) == Factors(2*x) assert Factors(x).mul(S.Zero).is_zero assert Factors(x).mul(1/x).is_one assert Factors(x**sqrt(2)**3).as_expr() == x**(2*sqrt(2)) assert Factors(x)**Factors(S(2)) == Factors(x**2) assert Factors(x).gcd(S.Zero) == Factors(x) assert Factors(x).lcm(S.Zero).is_zero assert Factors(S.Zero).div(x) == (Factors(S.Zero), Factors()) assert Factors(x).div(x) == (Factors(), Factors()) assert Factors({x: .2})/Factors({x: .2}) == Factors() assert Factors(x) != Factors() assert Factors(S.Zero).normal(x) == (Factors(S.Zero), Factors()) n, d = x**(2 + y), x**2 f = Factors(n) assert f.div(d) == f.normal(d) == (Factors(x**y), Factors()) assert f.gcd(d) == Factors() d = x**y assert f.div(d) == f.normal(d) == (Factors(x**2), Factors()) assert f.gcd(d) == Factors(d) n = d = 2**x f = Factors(n) assert f.div(d) == f.normal(d) == (Factors(), Factors()) assert f.gcd(d) == Factors(d) n, d = 2**x, 2**y f = Factors(n) assert f.div(d) == f.normal(d) == (Factors({S(2): x}), Factors({S(2): y})) assert f.gcd(d) == Factors() # extraction of constant only n = x**(x + 3) assert Factors(n).normal(x**-3) == (Factors({x: x + 6}), Factors({})) assert Factors(n).normal(x**3) == (Factors({x: x}), Factors({})) assert Factors(n).normal(x**4) == (Factors({x: x}), Factors({x: 1})) assert Factors(n).normal(x**(y - 3)) == \ (Factors({x: x + 6}), Factors({x: y})) assert Factors(n).normal(x**(y + 3)) == (Factors({x: x}), Factors({x: y})) assert Factors(n).normal(x**(y + 4)) == \ (Factors({x: x}), Factors({x: y + 1})) assert Factors(n).div(x**-3) == (Factors({x: x + 6}), Factors({})) assert Factors(n).div(x**3) == (Factors({x: x}), Factors({})) assert Factors(n).div(x**4) == (Factors({x: x}), Factors({x: 1})) assert Factors(n).div(x**(y - 3)) == \ (Factors({x: x + 6}), Factors({x: y})) assert Factors(n).div(x**(y + 3)) == (Factors({x: x}), Factors({x: y})) assert Factors(n).div(x**(y + 4)) == \ (Factors({x: x}), Factors({x: y + 1})) assert Factors(3 * x / 2) == Factors({3: 1, 2: -1, x: 1}) assert Factors(x * x / y) == Factors({x: 2, y: -1}) assert Factors(27 * x / y**9) == Factors({27: 1, x: 1, y: -9}) def test_Term(): a = Term(4*x*y**2/z/t**3) b = Term(2*x**3*y**5/t**3) assert a == Term(4, Factors({x: 1, y: 2}), Factors({z: 1, t: 3})) assert b == Term(2, Factors({x: 3, y: 5}), Factors({t: 3})) assert a.as_expr() == 4*x*y**2/z/t**3 assert b.as_expr() == 2*x**3*y**5/t**3 assert a.inv() == \ Term(S.One/4, Factors({z: 1, t: 3}), Factors({x: 1, y: 2})) assert b.inv() == Term(S.Half, Factors({t: 3}), Factors({x: 3, y: 5})) assert a.mul(b) == a*b == \ Term(8, Factors({x: 4, y: 7}), Factors({z: 1, t: 6})) assert a.quo(b) == a/b == Term(2, Factors({}), Factors({x: 2, y: 3, z: 1})) assert a.pow(3) == a**3 == \ Term(64, Factors({x: 3, y: 6}), Factors({z: 3, t: 9})) assert b.pow(3) == b**3 == Term(8, Factors({x: 9, y: 15}), Factors({t: 9})) assert a.pow(-3) == a**(-3) == \ Term(S.One/64, Factors({z: 3, t: 9}), Factors({x: 3, y: 6})) assert b.pow(-3) == b**(-3) == \ Term(S.One/8, Factors({t: 9}), Factors({x: 9, y: 15})) assert a.gcd(b) == Term(2, Factors({x: 1, y: 2}), Factors({t: 3})) assert a.lcm(b) == Term(4, Factors({x: 3, y: 5}), Factors({z: 1, t: 3})) a = Term(4*x*y**2/z/t**3) b = Term(2*x**3*y**5*t**7) assert a.mul(b) == Term(8, Factors({x: 4, y: 7, t: 4}), Factors({z: 1})) assert Term((2*x + 2)**3) == Term(8, Factors({x + 1: 3}), Factors({})) assert Term((2*x + 2)*(3*x + 6)**2) == \ Term(18, Factors({x + 1: 1, x + 2: 2}), Factors({})) def test_gcd_terms(): f = 2*(x + 1)*(x + 4)/(5*x**2 + 5) + (2*x + 2)*(x + 5)/(x**2 + 1)/5 + \ (2*x + 2)*(x + 6)/(5*x**2 + 5) assert _gcd_terms(f) == ((Rational(6, 5))*((1 + x)/(1 + x**2)), 5 + x, 1) assert _gcd_terms(Add.make_args(f)) == \ ((Rational(6, 5))*((1 + x)/(1 + x**2)), 5 + x, 1) newf = (Rational(6, 5))*((1 + x)*(5 + x)/(1 + x**2)) assert gcd_terms(f) == newf args = Add.make_args(f) # non-Basic sequences of terms treated as terms of Add assert gcd_terms(list(args)) == newf assert gcd_terms(tuple(args)) == newf assert gcd_terms(set(args)) == newf # but a Basic sequence is treated as a container assert gcd_terms(Tuple(*args)) != newf assert gcd_terms(Basic(Tuple(S(1), 3*y + 3*x*y), Tuple(S(1), S(3)))) == \ Basic(Tuple(S(1), 3*y*(x + 1)), Tuple(S(1), S(3))) # but we shouldn't change keys of a dictionary or some may be lost assert gcd_terms(Dict((x*(1 + y), S(2)), (x + x*y, y + x*y))) == \ Dict({x*(y + 1): S(2), x + x*y: y*(1 + x)}) assert gcd_terms((2*x + 2)**3 + (2*x + 2)**2) == 4*(x + 1)**2*(2*x + 3) assert gcd_terms(0) == 0 assert gcd_terms(1) == 1 assert gcd_terms(x) == x assert gcd_terms(2 + 2*x) == Mul(2, 1 + x, evaluate=False) arg = x*(2*x + 4*y) garg = 2*x*(x + 2*y) assert gcd_terms(arg) == garg assert gcd_terms(sin(arg)) == sin(garg) # issue 6139-like alpha, alpha1, alpha2, alpha3 = symbols('alpha:4') a = alpha**2 - alpha*x**2 + alpha + x**3 - x*(alpha + 1) rep = (alpha, (1 + sqrt(5))/2 + alpha1*x + alpha2*x**2 + alpha3*x**3) s = (a/(x - alpha)).subs(*rep).series(x, 0, 1) assert simplify(collect(s, x)) == -sqrt(5)/2 - Rational(3, 2) + O(x) # issue 5917 assert _gcd_terms([S.Zero, S.Zero]) == (0, 0, 1) assert _gcd_terms([2*x + 4]) == (2, x + 2, 1) eq = x/(x + 1/x) assert gcd_terms(eq, fraction=False) == eq eq = x/2/y + 1/x/y assert gcd_terms(eq, fraction=True, clear=True) == \ (x**2 + 2)/(2*x*y) assert gcd_terms(eq, fraction=True, clear=False) == \ (x**2/2 + 1)/(x*y) assert gcd_terms(eq, fraction=False, clear=True) == \ (x + 2/x)/(2*y) assert gcd_terms(eq, fraction=False, clear=False) == \ (x/2 + 1/x)/y def test_factor_terms(): A = Symbol('A', commutative=False) assert factor_terms(9*(x + x*y + 1) + (3*x + 3)**(2 + 2*x)) == \ 9*x*y + 9*x + _keep_coeff(S(3), x + 1)**_keep_coeff(S(2), x + 1) + 9 assert factor_terms(9*(x + x*y + 1) + (3)**(2 + 2*x)) == \ _keep_coeff(S(9), 3**(2*x) + x*y + x + 1) assert factor_terms(3**(2 + 2*x) + a*3**(2 + 2*x)) == \ 9*3**(2*x)*(a + 1) assert factor_terms(x + x*A) == \ x*(1 + A) assert factor_terms(sin(x + x*A)) == \ sin(x*(1 + A)) assert factor_terms((3*x + 3)**((2 + 2*x)/3)) == \ _keep_coeff(S(3), x + 1)**_keep_coeff(Rational(2, 3), x + 1) assert factor_terms(x + (x*y + x)**(3*x + 3)) == \ x + (x*(y + 1))**_keep_coeff(S(3), x + 1) assert factor_terms(a*(x + x*y) + b*(x*2 + y*x*2)) == \ x*(a + 2*b)*(y + 1) i = Integral(x, (x, 0, oo)) assert factor_terms(i) == i assert factor_terms(x/2 + y) == x/2 + y # fraction doesn't apply to integer denominators assert factor_terms(x/2 + y, fraction=True) == x/2 + y # clear *does* apply to the integer denominators assert factor_terms(x/2 + y, clear=True) == Mul(S.Half, x + 2*y, evaluate=False) # check radical extraction eq = sqrt(2) + sqrt(10) assert factor_terms(eq) == eq assert factor_terms(eq, radical=True) == sqrt(2)*(1 + sqrt(5)) eq = root(-6, 3) + root(6, 3) assert factor_terms(eq, radical=True) == 6**(S.One/3)*(1 + (-1)**(S.One/3)) eq = [x + x*y] ans = [x*(y + 1)] for c in [list, tuple, set]: assert factor_terms(c(eq)) == c(ans) assert factor_terms(Tuple(x + x*y)) == Tuple(x*(y + 1)) assert factor_terms(Interval(0, 1)) == Interval(0, 1) e = 1/sqrt(a/2 + 1) assert factor_terms(e, clear=False) == 1/sqrt(a/2 + 1) assert factor_terms(e, clear=True) == sqrt(2)/sqrt(a + 2) eq = x/(x + 1/x) + 1/(x**2 + 1) assert factor_terms(eq, fraction=False) == eq assert factor_terms(eq, fraction=True) == 1 assert factor_terms((1/(x**3 + x**2) + 2/x**2)*y) == \ y*(2 + 1/(x + 1))/x**2 # if not True, then processesing for this in factor_terms is not necessary assert gcd_terms(-x - y) == -x - y assert factor_terms(-x - y) == Mul(-1, x + y, evaluate=False) # if not True, then "special" processesing in factor_terms is not necessary assert gcd_terms(exp(Mul(-1, x + 1))) == exp(-x - 1) e = exp(-x - 2) + x assert factor_terms(e) == exp(Mul(-1, x + 2, evaluate=False)) + x assert factor_terms(e, sign=False) == e assert factor_terms(exp(-4*x - 2) - x) == -x + exp(Mul(-2, 2*x + 1, evaluate=False)) # sum/integral tests for F in (Sum, Integral): assert factor_terms(F(x, (y, 1, 10))) == x * F(1, (y, 1, 10)) assert factor_terms(F(x, (y, 1, 10)) + x) == x * (1 + F(1, (y, 1, 10))) assert factor_terms(F(x*y + x*y**2, (y, 1, 10))) == x*F(y*(y + 1), (y, 1, 10)) # expressions involving Pow terms with base 0 assert factor_terms(0**(x - 2) - 1) == 0**(x - 2) - 1 assert factor_terms(0**(x + 2) - 1) == 0**(x + 2) - 1 assert factor_terms((0**(x + 2) - 1).subs(x,-2)) == 0 def test_xreplace(): e = Mul(2, 1 + x, evaluate=False) assert e.xreplace({}) == e assert e.xreplace({y: x}) == e def test_factor_nc(): x, y = symbols('x,y') k = symbols('k', integer=True) n, m, o = symbols('n,m,o', commutative=False) # mul and multinomial expansion is needed from sympy.core.function import _mexpand e = x*(1 + y)**2 assert _mexpand(e) == x + x*2*y + x*y**2 def factor_nc_test(e): ex = _mexpand(e) assert ex.is_Add f = factor_nc(ex) assert not f.is_Add and _mexpand(f) == ex factor_nc_test(x*(1 + y)) factor_nc_test(n*(x + 1)) factor_nc_test(n*(x + m)) factor_nc_test((x + m)*n) factor_nc_test(n*m*(x*o + n*o*m)*n) s = Sum(x, (x, 1, 2)) factor_nc_test(x*(1 + s)) factor_nc_test(x*(1 + s)*s) factor_nc_test(x*(1 + sin(s))) factor_nc_test((1 + n)**2) factor_nc_test((x + n)*(x + m)*(x + y)) factor_nc_test(x*(n*m + 1)) factor_nc_test(x*(n*m + x)) factor_nc_test(x*(x*n*m + 1)) factor_nc_test(n*(m/x + o)) factor_nc_test(m*(n + o/2)) factor_nc_test(x*n*(x*m + 1)) factor_nc_test(x*(m*n + x*n*m)) factor_nc_test(n*(1 - m)*n**2) factor_nc_test((n + m)**2) factor_nc_test((n - m)*(n + m)**2) factor_nc_test((n + m)**2*(n - m)) factor_nc_test((m - n)*(n + m)**2*(n - m)) assert factor_nc(n*(n + n*m)) == n**2*(1 + m) assert factor_nc(m*(m*n + n*m*n**2)) == m*(m + n*m*n)*n eq = m*sin(n) - sin(n)*m assert factor_nc(eq) == eq # for coverage: from sympy.physics.secondquant import Commutator from sympy.polys.polytools import factor eq = 1 + x*Commutator(m, n) assert factor_nc(eq) == eq eq = x*Commutator(m, n) + x*Commutator(m, o)*Commutator(m, n) assert factor(eq) == x*(1 + Commutator(m, o))*Commutator(m, n) # issue 6534 assert (2*n + 2*m).factor() == 2*(n + m) # issue 6701 _n = symbols('nz', zero=False, commutative=False) assert factor_nc(_n**k + _n**(k + 1)) == _n**k*(1 + _n) assert factor_nc((m*n)**k + (m*n)**(k + 1)) == (1 + m*n)*(m*n)**k # issue 6918 assert factor_nc(-n*(2*x**2 + 2*x)) == -2*n*x*(x + 1) def test_issue_6360(): a, b = symbols("a b") apb = a + b eq = apb + apb**2*(-2*a - 2*b) assert factor_terms(sub_pre(eq)) == a + b - 2*(a + b)**3 def test_issue_7903(): a = symbols(r'a', real=True) t = exp(I*cos(a)) + exp(-I*sin(a)) assert t.simplify() def test_issue_8263(): F, G = symbols('F, G', commutative=False, cls=Function) x, y = symbols('x, y') expr, dummies, _ = _mask_nc(F(x)*G(y) - G(y)*F(x)) for v in dummies.values(): assert not v.is_commutative assert not expr.is_zero def test_monotonic_sign(): F = _monotonic_sign x = symbols('x') assert F(x) is None assert F(-x) is None assert F(Dummy(prime=True)) == 2 assert F(Dummy(prime=True, odd=True)) == 3 assert F(Dummy(composite=True)) == 4 assert F(Dummy(composite=True, odd=True)) == 9 assert F(Dummy(positive=True, integer=True)) == 1 assert F(Dummy(positive=True, even=True)) == 2 assert F(Dummy(positive=True, even=True, prime=False)) == 4 assert F(Dummy(negative=True, integer=True)) == -1 assert F(Dummy(negative=True, even=True)) == -2 assert F(Dummy(zero=True)) == 0 assert F(Dummy(nonnegative=True)) == 0 assert F(Dummy(nonpositive=True)) == 0 assert F(Dummy(positive=True) + 1).is_positive assert F(Dummy(positive=True, integer=True) - 1).is_nonnegative assert F(Dummy(positive=True) - 1) is None assert F(Dummy(negative=True) + 1) is None assert F(Dummy(negative=True, integer=True) - 1).is_nonpositive assert F(Dummy(negative=True) - 1).is_negative assert F(-Dummy(positive=True) + 1) is None assert F(-Dummy(positive=True, integer=True) - 1).is_negative assert F(-Dummy(positive=True) - 1).is_negative assert F(-Dummy(negative=True) + 1).is_positive assert F(-Dummy(negative=True, integer=True) - 1).is_nonnegative assert F(-Dummy(negative=True) - 1) is None x = Dummy(negative=True) assert F(x**3).is_nonpositive assert F(x**3 + log(2)*x - 1).is_negative x = Dummy(positive=True) assert F(-x**3).is_nonpositive p = Dummy(positive=True) assert F(1/p).is_positive assert F(p/(p + 1)).is_positive p = Dummy(nonnegative=True) assert F(p/(p + 1)).is_nonnegative p = Dummy(positive=True) assert F(-1/p).is_negative p = Dummy(nonpositive=True) assert F(p/(-p + 1)).is_nonpositive p = Dummy(positive=True, integer=True) q = Dummy(positive=True, integer=True) assert F(-2/p/q).is_negative assert F(-2/(p - 1)/q) is None assert F((p - 1)*q + 1).is_positive assert F(-(p - 1)*q - 1).is_negative def test_issue_17256(): from sympy.sets.fancysets import Range x = Symbol('x') s1 = Sum(x + 1, (x, 1, 9)) s2 = Sum(x + 1, (x, Range(1, 10))) a = Symbol('a') r1 = s1.xreplace({x:a}) r2 = s2.xreplace({x:a}) assert r1.doit() == r2.doit() s1 = Sum(x + 1, (x, 0, 9)) s2 = Sum(x + 1, (x, Range(10))) a = Symbol('a') r1 = s1.xreplace({x:a}) r2 = s2.xreplace({x:a}) assert r1 == r2 def test_issue_21623(): from sympy.matrices.expressions.matexpr import MatrixSymbol M = MatrixSymbol('X', 2, 2) assert gcd_terms(M[0,0], 1) == M[0,0]