def _(expr): base, exp = expr.base, expr.exp return [ (Q.real(base) & Q.even(exp) & Q.nonnegative(exp)) >> Q.nonnegative(expr), (Q.nonnegative(base) & Q.odd(exp) & Q.nonnegative(exp)) >> Q.nonnegative(expr), (Q.nonpositive(base) & Q.odd(exp) & Q.nonnegative(exp)) >> Q.nonpositive(expr), Equivalent(Q.zero(expr), Q.zero(base) & Q.positive(exp)) ]
def test_old_assump(): assert satask(Q.positive(1)) is True assert satask(Q.positive(-1)) is False assert satask(Q.positive(0)) is False assert satask(Q.positive(I)) is False assert satask(Q.positive(pi)) is True assert satask(Q.negative(1)) is False assert satask(Q.negative(-1)) is True assert satask(Q.negative(0)) is False assert satask(Q.negative(I)) is False assert satask(Q.negative(pi)) is False assert satask(Q.zero(1)) is False assert satask(Q.zero(-1)) is False assert satask(Q.zero(0)) is True assert satask(Q.zero(I)) is False assert satask(Q.zero(pi)) is False assert satask(Q.nonzero(1)) is True assert satask(Q.nonzero(-1)) is True assert satask(Q.nonzero(0)) is False assert satask(Q.nonzero(I)) is False assert satask(Q.nonzero(pi)) is True assert satask(Q.nonpositive(1)) is False assert satask(Q.nonpositive(-1)) is True assert satask(Q.nonpositive(0)) is True assert satask(Q.nonpositive(I)) is False assert satask(Q.nonpositive(pi)) is False assert satask(Q.nonnegative(1)) is True assert satask(Q.nonnegative(-1)) is False assert satask(Q.nonnegative(0)) is True assert satask(Q.nonnegative(I)) is False assert satask(Q.nonnegative(pi)) is True
registry[klass] |= {fact} for klass, fact in [ (Mul, Equivalent(Q.zero, AnyArgs(Q.zero))), (MatMul, Implies(AllArgs(Q.square), Equivalent(Q.invertible, AllArgs(Q.invertible)))), (Add, Implies(AllArgs(Q.positive), Q.positive)), (Add, Implies(AllArgs(Q.negative), Q.negative)), (Mul, Implies(AllArgs(Q.positive), Q.positive)), (Mul, Implies(AllArgs(Q.commutative), Q.commutative)), (Mul, Implies(AllArgs(Q.real), Q.commutative)), (Pow, CustomLambda(lambda power: Implies(Q.real(power.base) & Q.even(power.exp) & Q.nonnegative(power.exp), Q.nonnegative(power)))), (Pow, CustomLambda(lambda power: Implies(Q.nonnegative(power.base) & Q.odd(power.exp) & Q.nonnegative(power.exp), Q.nonnegative(power)))), (Pow, CustomLambda(lambda power: Implies(Q.nonpositive(power.base) & Q.odd(power.exp) & Q.nonnegative(power.exp), Q.nonpositive(power)))), # This one can still be made easier to read. I think we need basic pattern # matching, so that we can just write Equivalent(Q.zero(x**y), Q.zero(x) & Q.positive(y)) (Pow, CustomLambda(lambda power: Equivalent(Q.zero(power), Q.zero(power.base) & Q.positive(power.exp)))), (Integer, CheckIsPrime(Q.prime)), # Implicitly assumes Mul has more than one arg # Would be AllArgs(Q.prime | Q.composite) except 1 is composite (Mul, Implies(AllArgs(Q.prime), ~Q.prime)), # More advanced prime assumptions will require inequalities, as 1 provides # a corner case. (Mul, Implies(AllArgs(Q.imaginary | Q.real), Implies(ExactlyOneArg(Q.imaginary), Q.imaginary))), (Mul, Implies(AllArgs(Q.real), Q.real)), (Add, Implies(AllArgs(Q.real), Q.real)), # General Case: Odd number of imaginary args implies mul is imaginary(To be implemented) (Mul, Implies(AllArgs(Q.real), Implies(ExactlyOneArg(Q.irrational),
registry[klass] |= {fact} for klass, fact in [ (Mul, Equivalent(Q.zero, AnyArgs(Q.zero))), (MatMul, Implies(AllArgs(Q.square), Equivalent(Q.invertible, AllArgs(Q.invertible)))), (Add, Implies(AllArgs(Q.positive), Q.positive)), (Add, Implies(AllArgs(Q.negative), Q.negative)), (Mul, Implies(AllArgs(Q.positive), Q.positive)), (Mul, Implies(AllArgs(Q.commutative), Q.commutative)), (Mul, Implies(AllArgs(Q.real), Q.commutative)), (Pow, CustomLambda(lambda power: Implies(Q.real(power.base) & Q.even(power.exp) & Q.nonnegative(power.exp), Q.nonnegative(power)))), (Pow, CustomLambda(lambda power: Implies(Q.nonnegative(power.base) & Q.odd(power.exp) & Q.nonnegative(power.exp), Q.nonnegative(power)))), (Pow, CustomLambda(lambda power: Implies(Q.nonpositive(power.base) & Q.odd(power.exp) & Q.nonnegative(power.exp), Q.nonpositive(power)))), # This one can still be made easier to read. I think we need basic pattern # matching, so that we can just write Equivalent(Q.zero(x**y), Q.zero(x) & Q.positive(y)) (Pow, CustomLambda(lambda power: Equivalent(Q.zero(power), Q.zero(power.base) & Q.positive(power.exp)))), (Integer, CheckIsPrime(Q.prime)), # Implicitly assumes Mul has more than one arg # Would be AllArgs(Q.prime | Q.composite) except 1 is composite (Mul, Implies(AllArgs(Q.prime), ~Q.prime)), # More advanced prime assumptions will require inequalities, as 1 provides # a corner case. (Mul, Implies(AllArgs(Q.imaginary | Q.real), Implies(ExactlyOneArg(Q.imaginary), Q.imaginary))), (Mul, Implies(AllArgs(Q.real), Q.real)), (Add, Implies(AllArgs(Q.real), Q.real)), # General Case: Odd number of imaginary args implies mul is imaginary(To be implemented) (Mul, Implies(AllArgs(Q.real), Implies(ExactlyOneArg(Q.irrational),
(Add, Implies(AllArgs(Q.positive), Q.positive)), (Add, Implies(AllArgs(Q.negative), Q.negative)), (Mul, Implies(AllArgs(Q.positive), Q.positive)), (Mul, Implies(AllArgs(Q.commutative), Q.commutative)), (Mul, Implies(AllArgs(Q.real), Q.commutative)), (Pow, CustomLambda(lambda power: Implies( Q.real(power.base) & Q.even(power.exp) & Q.nonnegative(power.exp), Q.nonnegative(power)))), (Pow, CustomLambda(lambda power: Implies( Q.nonnegative(power.base) & Q.odd(power.exp) & Q.nonnegative( power.exp), Q.nonnegative(power)))), (Pow, CustomLambda(lambda power: Implies( Q.nonpositive(power.base) & Q.odd(power.exp) & Q.nonnegative( power.exp), Q.nonpositive(power)))), # This one can still be made easier to read. I think we need basic pattern # matching, so that we can just write Equivalent(Q.zero(x**y), Q.zero(x) & Q.positive(y)) (Pow, CustomLambda( lambda power: Equivalent(Q.zero(power), Q.zero(power.base) & Q.positive(power.exp))) ), (Integer, CheckIsPrime(Q.prime)), # Implicitly assumes Mul has more than one arg # Would be AllArgs(Q.prime | Q.composite) except 1 is composite (Mul, Implies(AllArgs(Q.prime), ~Q.prime)), # More advanced prime assumptions will require inequalities, as 1 provides # a corner case.
def test_pow_pos_neg(): assert satask(Q.nonnegative(x**2), Q.positive(x)) is True assert satask(Q.nonpositive(x**2), Q.positive(x)) is False assert satask(Q.positive(x**2), Q.positive(x)) is True assert satask(Q.negative(x**2), Q.positive(x)) is False assert satask(Q.real(x**2), Q.positive(x)) is True assert satask(Q.nonnegative(x**2), Q.negative(x)) is True assert satask(Q.nonpositive(x**2), Q.negative(x)) is False assert satask(Q.positive(x**2), Q.negative(x)) is True assert satask(Q.negative(x**2), Q.negative(x)) is False assert satask(Q.real(x**2), Q.negative(x)) is True assert satask(Q.nonnegative(x**2), Q.nonnegative(x)) is True assert satask(Q.nonpositive(x**2), Q.nonnegative(x)) is None assert satask(Q.positive(x**2), Q.nonnegative(x)) is None assert satask(Q.negative(x**2), Q.nonnegative(x)) is False assert satask(Q.real(x**2), Q.nonnegative(x)) is True assert satask(Q.nonnegative(x**2), Q.nonpositive(x)) is True assert satask(Q.nonpositive(x**2), Q.nonpositive(x)) is None assert satask(Q.positive(x**2), Q.nonpositive(x)) is None assert satask(Q.negative(x**2), Q.nonpositive(x)) is False assert satask(Q.real(x**2), Q.nonpositive(x)) is True assert satask(Q.nonnegative(x**3), Q.positive(x)) is True assert satask(Q.nonpositive(x**3), Q.positive(x)) is False assert satask(Q.positive(x**3), Q.positive(x)) is True assert satask(Q.negative(x**3), Q.positive(x)) is False assert satask(Q.real(x**3), Q.positive(x)) is True assert satask(Q.nonnegative(x**3), Q.negative(x)) is False assert satask(Q.nonpositive(x**3), Q.negative(x)) is True assert satask(Q.positive(x**3), Q.negative(x)) is False assert satask(Q.negative(x**3), Q.negative(x)) is True assert satask(Q.real(x**3), Q.negative(x)) is True assert satask(Q.nonnegative(x**3), Q.nonnegative(x)) is True assert satask(Q.nonpositive(x**3), Q.nonnegative(x)) is None assert satask(Q.positive(x**3), Q.nonnegative(x)) is None assert satask(Q.negative(x**3), Q.nonnegative(x)) is False assert satask(Q.real(x**3), Q.nonnegative(x)) is True assert satask(Q.nonnegative(x**3), Q.nonpositive(x)) is None assert satask(Q.nonpositive(x**3), Q.nonpositive(x)) is True assert satask(Q.positive(x**3), Q.nonpositive(x)) is False assert satask(Q.negative(x**3), Q.nonpositive(x)) is None assert satask(Q.real(x**3), Q.nonpositive(x)) is True # If x is zero, x**negative is not real. assert satask(Q.nonnegative(x**-2), Q.nonpositive(x)) is None assert satask(Q.nonpositive(x**-2), Q.nonpositive(x)) is None assert satask(Q.positive(x**-2), Q.nonpositive(x)) is None assert satask(Q.negative(x**-2), Q.nonpositive(x)) is None assert satask(Q.real(x**-2), Q.nonpositive(x)) is None