I am done

rl/Lib/site-packages/sympy/sets/handlers/add.py

@@ -0,0 +1,79 @@
+from sympy.core.numbers import oo, Infinity, NegativeInfinity
+from sympy.core.singleton import S
+from sympy.core import Basic, Expr
+from sympy.multipledispatch import Dispatcher
+from sympy.sets import Interval, FiniteSet
+
+
+
+# XXX: The functions in this module are clearly not tested and are broken in a
+# number of ways.
+
+_set_add = Dispatcher('_set_add')
+_set_sub = Dispatcher('_set_sub')
+
+
+@_set_add.register(Basic, Basic)
+def _(x, y):
+    return None
+
+
+@_set_add.register(Expr, Expr)
+def _(x, y):
+    return x+y
+
+
+@_set_add.register(Interval, Interval)
+def _(x, y):
+    """
+    Additions in interval arithmetic
+    https://en.wikipedia.org/wiki/Interval_arithmetic
+    """
+    return Interval(x.start + y.start, x.end + y.end,
+                    x.left_open or y.left_open, x.right_open or y.right_open)
+
+
+@_set_add.register(Interval, Infinity)
+def _(x, y):
+    if x.start is S.NegativeInfinity:
+        return Interval(-oo, oo)
+    return FiniteSet({S.Infinity})
+
+@_set_add.register(Interval, NegativeInfinity)
+def _(x, y):
+    if x.end is S.Infinity:
+        return Interval(-oo, oo)
+    return FiniteSet({S.NegativeInfinity})
+
+
+@_set_sub.register(Basic, Basic)
+def _(x, y):
+    return None
+
+
+@_set_sub.register(Expr, Expr)
+def _(x, y):
+    return x-y
+
+
+@_set_sub.register(Interval, Interval)
+def _(x, y):
+    """
+    Subtractions in interval arithmetic
+    https://en.wikipedia.org/wiki/Interval_arithmetic
+    """
+    return Interval(x.start - y.end, x.end - y.start,
+                    x.left_open or y.right_open, x.right_open or y.left_open)
+
+
+@_set_sub.register(Interval, Infinity)
+def _(x, y):
+    if x.start is S.NegativeInfinity:
+        return Interval(-oo, oo)
+    return FiniteSet(-oo)
+
+@_set_sub.register(Interval, NegativeInfinity)
+def _(x, y):
+    if x.start is S.NegativeInfinity:
+        return Interval(-oo, oo)
+    return FiniteSet(-oo)

rl/Lib/site-packages/sympy/sets/handlers/comparison.py

@@ -0,0 +1,53 @@
+from sympy.core.relational import Eq, is_eq
+from sympy.core.basic import Basic
+from sympy.core.logic import fuzzy_and, fuzzy_bool
+from sympy.logic.boolalg import And
+from sympy.multipledispatch import dispatch
+from sympy.sets.sets import tfn, ProductSet, Interval, FiniteSet, Set
+
+
+@dispatch(Interval, FiniteSet) # type:ignore
+def _eval_is_eq(lhs, rhs): # noqa: F811
+    return False
+
+
+@dispatch(FiniteSet, Interval) # type:ignore
+def _eval_is_eq(lhs, rhs): # noqa: F811
+    return False
+
+
+@dispatch(Interval, Interval) # type:ignore
+def _eval_is_eq(lhs, rhs): # noqa: F811
+    return And(Eq(lhs.left, rhs.left),
+               Eq(lhs.right, rhs.right),
+               lhs.left_open == rhs.left_open,
+               lhs.right_open == rhs.right_open)
+
+@dispatch(FiniteSet, FiniteSet) # type:ignore
+def _eval_is_eq(lhs, rhs): # noqa: F811
+    def all_in_both():
+        s_set = set(lhs.args)
+        o_set = set(rhs.args)
+        yield fuzzy_and(lhs._contains(e) for e in o_set - s_set)
+        yield fuzzy_and(rhs._contains(e) for e in s_set - o_set)
+
+    return tfn[fuzzy_and(all_in_both())]
+
+
+@dispatch(ProductSet, ProductSet) # type:ignore
+def _eval_is_eq(lhs, rhs): # noqa: F811
+    if len(lhs.sets) != len(rhs.sets):
+        return False
+
+    eqs = (is_eq(x, y) for x, y in zip(lhs.sets, rhs.sets))
+    return tfn[fuzzy_and(map(fuzzy_bool, eqs))]
+
+
+@dispatch(Set, Basic) # type:ignore
+def _eval_is_eq(lhs, rhs): # noqa: F811
+    return False
+
+
+@dispatch(Set, Set) # type:ignore
+def _eval_is_eq(lhs, rhs): # noqa: F811
+    return tfn[fuzzy_and(a.is_subset(b) for a, b in [(lhs, rhs), (rhs, lhs)])]

rl/Lib/site-packages/sympy/sets/handlers/functions.py

@@ -0,0 +1,262 @@
+from sympy.core.singleton import S
+from sympy.sets.sets import Set
+from sympy.calculus.singularities import singularities
+from sympy.core import Expr, Add
+from sympy.core.function import Lambda, FunctionClass, diff, expand_mul
+from sympy.core.numbers import Float, oo
+from sympy.core.symbol import Dummy, symbols, Wild
+from sympy.functions.elementary.exponential import exp, log
+from sympy.functions.elementary.miscellaneous import Min, Max
+from sympy.logic.boolalg import true
+from sympy.multipledispatch import Dispatcher
+from sympy.sets import (imageset, Interval, FiniteSet, Union, ImageSet,
+    Intersection, Range, Complement)
+from sympy.sets.sets import EmptySet, is_function_invertible_in_set
+from sympy.sets.fancysets import Integers, Naturals, Reals
+from sympy.functions.elementary.exponential import match_real_imag
+
+
+_x, _y = symbols("x y")
+
+FunctionUnion = (FunctionClass, Lambda)
+
+_set_function = Dispatcher('_set_function')
+
+
+@_set_function.register(FunctionClass, Set)
+def _(f, x):
+    return None
+
+@_set_function.register(FunctionUnion, FiniteSet)
+def _(f, x):
+    return FiniteSet(*map(f, x))
+
+@_set_function.register(Lambda, Interval)
+def _(f, x):
+    from sympy.solvers.solveset import solveset
+    from sympy.series import limit
+    # TODO: handle functions with infinitely many solutions (eg, sin, tan)
+    # TODO: handle multivariate functions
+
+    expr = f.expr
+    if len(expr.free_symbols) > 1 or len(f.variables) != 1:
+        return
+    var = f.variables[0]
+    if not var.is_real:
+        if expr.subs(var, Dummy(real=True)).is_real is False:
+            return
+
+    if expr.is_Piecewise:
+        result = S.EmptySet
+        domain_set = x
+        for (p_expr, p_cond) in expr.args:
+            if p_cond is true:
+                intrvl = domain_set
+            else:
+                intrvl = p_cond.as_set()
+                intrvl = Intersection(domain_set, intrvl)
+
+            if p_expr.is_Number:
+                image = FiniteSet(p_expr)
+            else:
+                image = imageset(Lambda(var, p_expr), intrvl)
+            result = Union(result, image)
+
+            # remove the part which has been `imaged`
+            domain_set = Complement(domain_set, intrvl)
+            if domain_set is S.EmptySet:
+                break
+        return result
+
+    if not x.start.is_comparable or not x.end.is_comparable:
+        return
+
+    try:
+        from sympy.polys.polyutils import _nsort
+        sing = list(singularities(expr, var, x))
+        if len(sing) > 1:
+            sing = _nsort(sing)
+    except NotImplementedError:
+        return
+
+    if x.left_open:
+        _start = limit(expr, var, x.start, dir="+")
+    elif x.start not in sing:
+        _start = f(x.start)
+    if x.right_open:
+        _end = limit(expr, var, x.end, dir="-")
+    elif x.end not in sing:
+        _end = f(x.end)
+
+    if len(sing) == 0:
+        soln_expr = solveset(diff(expr, var), var)
+        if not (isinstance(soln_expr, FiniteSet)
+                or soln_expr is S.EmptySet):
+            return
+        solns = list(soln_expr)
+
+        extr = [_start, _end] + [f(i) for i in solns
+                                 if i.is_real and i in x]
+        start, end = Min(*extr), Max(*extr)
+
+        left_open, right_open = False, False
+        if _start <= _end:
+            # the minimum or maximum value can occur simultaneously
+            # on both the edge of the interval and in some interior
+            # point
+            if start == _start and start not in solns:
+                left_open = x.left_open
+            if end == _end and end not in solns:
+                right_open = x.right_open
+        else:
+            if start == _end and start not in solns:
+                left_open = x.right_open
+            if end == _start and end not in solns:
+                right_open = x.left_open
+
+        return Interval(start, end, left_open, right_open)
+    else:
+        return imageset(f, Interval(x.start, sing[0],
+                                    x.left_open, True)) + \
+            Union(*[imageset(f, Interval(sing[i], sing[i + 1], True, True))
+                    for i in range(0, len(sing) - 1)]) + \
+            imageset(f, Interval(sing[-1], x.end, True, x.right_open))
+
+@_set_function.register(FunctionClass, Interval)
+def _(f, x):
+    if f == exp:
+        return Interval(exp(x.start), exp(x.end), x.left_open, x.right_open)
+    elif f == log:
+        return Interval(log(x.start), log(x.end), x.left_open, x.right_open)
+    return ImageSet(Lambda(_x, f(_x)), x)
+
+@_set_function.register(FunctionUnion, Union)
+def _(f, x):
+    return Union(*(imageset(f, arg) for arg in x.args))
+
+@_set_function.register(FunctionUnion, Intersection)
+def _(f, x):
+    # If the function is invertible, intersect the maps of the sets.
+    if is_function_invertible_in_set(f, x):
+        return Intersection(*(imageset(f, arg) for arg in x.args))
+    else:
+        return ImageSet(Lambda(_x, f(_x)), x)
+
+@_set_function.register(FunctionUnion, EmptySet)
+def _(f, x):
+    return x
+
+@_set_function.register(FunctionUnion, Set)
+def _(f, x):
+    return ImageSet(Lambda(_x, f(_x)), x)
+
+@_set_function.register(FunctionUnion, Range)
+def _(f, self):
+    if not self:
+        return S.EmptySet
+    if not isinstance(f.expr, Expr):
+        return
+    if self.size == 1:
+        return FiniteSet(f(self[0]))
+    if f is S.IdentityFunction:
+        return self
+
+    x = f.variables[0]
+    expr = f.expr
+    # handle f that is linear in f's variable
+    if x not in expr.free_symbols or x in expr.diff(x).free_symbols:
+        return
+    if self.start.is_finite:
+        F = f(self.step*x + self.start)  # for i in range(len(self))
+    else:
+        F = f(-self.step*x + self[-1])
+    F = expand_mul(F)
+    if F != expr:
+        return imageset(x, F, Range(self.size))
+
+@_set_function.register(FunctionUnion, Integers)
+def _(f, self):
+    expr = f.expr
+    if not isinstance(expr, Expr):
+        return
+
+    n = f.variables[0]
+    if expr == abs(n):
+        return S.Naturals0
+
+    # f(x) + c and f(-x) + c cover the same integers
+    # so choose the form that has the fewest negatives
+    c = f(0)
+    fx = f(n) - c
+    f_x = f(-n) - c
+    neg_count = lambda e: sum(_.could_extract_minus_sign()
+        for _ in Add.make_args(e))
+    if neg_count(f_x) < neg_count(fx):
+        expr = f_x + c
+
+    a = Wild('a', exclude=[n])
+    b = Wild('b', exclude=[n])
+    match = expr.match(a*n + b)
+    if match and match[a] and (
+            not match[a].atoms(Float) and
+            not match[b].atoms(Float)):
+        # canonical shift
+        a, b = match[a], match[b]
+        if a in [1, -1]:
+            # drop integer addends in b
+            nonint = []
+            for bi in Add.make_args(b):
+                if not bi.is_integer:
+                    nonint.append(bi)
+            b = Add(*nonint)
+        if b.is_number and a.is_real:
+            # avoid Mod for complex numbers, #11391
+            br, bi = match_real_imag(b)
+            if br and br.is_comparable and a.is_comparable:
+                br %= a
+                b = br + S.ImaginaryUnit*bi
+        elif b.is_number and a.is_imaginary:
+            br, bi = match_real_imag(b)
+            ai = a/S.ImaginaryUnit
+            if bi and bi.is_comparable and ai.is_comparable:
+                bi %= ai
+                b = br + S.ImaginaryUnit*bi
+        expr = a*n + b
+
+    if expr != f.expr:
+        return ImageSet(Lambda(n, expr), S.Integers)
+
+
+@_set_function.register(FunctionUnion, Naturals)
+def _(f, self):
+    expr = f.expr
+    if not isinstance(expr, Expr):
+        return
+
+    x = f.variables[0]
+    if not expr.free_symbols - {x}:
+        if expr == abs(x):
+            if self is S.Naturals:
+                return self
+            return S.Naturals0
+        step = expr.coeff(x)
+        c = expr.subs(x, 0)
+        if c.is_Integer and step.is_Integer and expr == step*x + c:
+            if self is S.Naturals:
+                c += step
+            if step > 0:
+                if step == 1:
+                    if c == 0:
+                        return S.Naturals0
+                    elif c == 1:
+                        return S.Naturals
+                return Range(c, oo, step)
+            return Range(c, -oo, step)
+
+
+@_set_function.register(FunctionUnion, Reals)
+def _(f, self):
+    expr = f.expr
+    if not isinstance(expr, Expr):
+        return
+    return _set_function(f, Interval(-oo, oo))

rl/Lib/site-packages/sympy/sets/handlers/intersection.py

@@ -0,0 +1,533 @@
+from sympy.core.basic import _aresame
+from sympy.core.function import Lambda, expand_complex
+from sympy.core.mul import Mul
+from sympy.core.numbers import ilcm, Float
+from sympy.core.relational import Eq
+from sympy.core.singleton import S
+from sympy.core.symbol import (Dummy, symbols)
+from sympy.core.sorting import ordered
+from sympy.functions.elementary.complexes import sign
+from sympy.functions.elementary.integers import floor, ceiling
+from sympy.sets.fancysets import ComplexRegion
+from sympy.sets.sets import (FiniteSet, Intersection, Interval, Set, Union)
+from sympy.multipledispatch import Dispatcher
+from sympy.sets.conditionset import ConditionSet
+from sympy.sets.fancysets import (Integers, Naturals, Reals, Range,
+    ImageSet, Rationals)
+from sympy.sets.sets import EmptySet, UniversalSet, imageset, ProductSet
+from sympy.simplify.radsimp import numer
+
+
+intersection_sets = Dispatcher('intersection_sets')
+
+
+@intersection_sets.register(ConditionSet, ConditionSet)
+def _(a, b):
+    return None
+
+@intersection_sets.register(ConditionSet, Set)
+def _(a, b):
+    return ConditionSet(a.sym, a.condition, Intersection(a.base_set, b))
+
+@intersection_sets.register(Naturals, Integers)
+def _(a, b):
+    return a
+
+@intersection_sets.register(Naturals, Naturals)
+def _(a, b):
+    return a if a is S.Naturals else b
+
+@intersection_sets.register(Interval, Naturals)
+def _(a, b):
+    return intersection_sets(b, a)
+
+@intersection_sets.register(ComplexRegion, Set)
+def _(self, other):
+    if other.is_ComplexRegion:
+        # self in rectangular form
+        if (not self.polar) and (not other.polar):
+            return ComplexRegion(Intersection(self.sets, other.sets))
+
+        # self in polar form
+        elif self.polar and other.polar:
+            r1, theta1 = self.a_interval, self.b_interval
+            r2, theta2 = other.a_interval, other.b_interval
+            new_r_interval = Intersection(r1, r2)
+            new_theta_interval = Intersection(theta1, theta2)
+
+            # 0 and 2*Pi means the same
+            if ((2*S.Pi in theta1 and S.Zero in theta2) or
+               (2*S.Pi in theta2 and S.Zero in theta1)):
+                new_theta_interval = Union(new_theta_interval,
+                                           FiniteSet(0))
+            return ComplexRegion(new_r_interval*new_theta_interval,
+                                polar=True)
+
+
+    if other.is_subset(S.Reals):
+        new_interval = []
+        x = symbols("x", cls=Dummy, real=True)
+
+        # self in rectangular form
+        if not self.polar:
+            for element in self.psets:
+                if S.Zero in element.args[1]:
+                    new_interval.append(element.args[0])
+            new_interval = Union(*new_interval)
+            return Intersection(new_interval, other)
+
+        # self in polar form
+        elif self.polar:
+            for element in self.psets:
+                if S.Zero in element.args[1]:
+                    new_interval.append(element.args[0])
+                if S.Pi in element.args[1]:
+                    new_interval.append(ImageSet(Lambda(x, -x), element.args[0]))
+                if S.Zero in element.args[0]:
+                    new_interval.append(FiniteSet(0))
+            new_interval = Union(*new_interval)
+            return Intersection(new_interval, other)
+
+@intersection_sets.register(Integers, Reals)
+def _(a, b):
+    return a
+
+@intersection_sets.register(Range, Interval)
+def _(a, b):
+    # Check that there are no symbolic arguments
+    if not all(i.is_number for i in a.args + b.args[:2]):
+        return
+
+    # In case of null Range, return an EmptySet.
+    if a.size == 0:
+        return S.EmptySet
+
+    # trim down to self's size, and represent
+    # as a Range with step 1.
+    start = ceiling(max(b.inf, a.inf))
+    if start not in b:
+        start += 1
+    end = floor(min(b.sup, a.sup))
+    if end not in b:
+        end -= 1
+    return intersection_sets(a, Range(start, end + 1))
+
+@intersection_sets.register(Range, Naturals)
+def _(a, b):
+    return intersection_sets(a, Interval(b.inf, S.Infinity))
+
+@intersection_sets.register(Range, Range)
+def _(a, b):
+    # Check that there are no symbolic range arguments
+    if not all(all(v.is_number for v in r.args) for r in [a, b]):
+        return None
+
+    # non-overlap quick exits
+    if not b:
+        return S.EmptySet
+    if not a:
+        return S.EmptySet
+    if b.sup < a.inf:
+        return S.EmptySet
+    if b.inf > a.sup:
+        return S.EmptySet
+
+    # work with finite end at the start
+    r1 = a
+    if r1.start.is_infinite:
+        r1 = r1.reversed
+    r2 = b
+    if r2.start.is_infinite:
+        r2 = r2.reversed
+
+    # If both ends are infinite then it means that one Range is just the set
+    # of all integers (the step must be 1).
+    if r1.start.is_infinite:
+        return b
+    if r2.start.is_infinite:
+        return a
+
+    from sympy.solvers.diophantine.diophantine import diop_linear
+
+    # this equation represents the values of the Range;
+    # it's a linear equation
+    eq = lambda r, i: r.start + i*r.step
+
+    # we want to know when the two equations might
+    # have integer solutions so we use the diophantine
+    # solver
+    va, vb = diop_linear(eq(r1, Dummy('a')) - eq(r2, Dummy('b')))
+
+    # check for no solution
+    no_solution = va is None and vb is None
+    if no_solution:
+        return S.EmptySet
+
+    # there is a solution
+    # -------------------
+
+    # find the coincident point, c
+    a0 = va.as_coeff_Add()[0]
+    c = eq(r1, a0)
+
+    # find the first point, if possible, in each range
+    # since c may not be that point
+    def _first_finite_point(r1, c):
+        if c == r1.start:
+            return c
+        # st is the signed step we need to take to
+        # get from c to r1.start
+        st = sign(r1.start - c)*step
+        # use Range to calculate the first point:
+        # we want to get as close as possible to
+        # r1.start; the Range will not be null since
+        # it will at least contain c
+        s1 = Range(c, r1.start + st, st)[-1]
+        if s1 == r1.start:
+            pass
+        else:
+            # if we didn't hit r1.start then, if the
+            # sign of st didn't match the sign of r1.step
+            # we are off by one and s1 is not in r1
+            if sign(r1.step) != sign(st):
+                s1 -= st
+        if s1 not in r1:
+            return
+        return s1
+
+    # calculate the step size of the new Range
+    step = abs(ilcm(r1.step, r2.step))
+    s1 = _first_finite_point(r1, c)
+    if s1 is None:
+        return S.EmptySet
+    s2 = _first_finite_point(r2, c)
+    if s2 is None:
+        return S.EmptySet
+
+    # replace the corresponding start or stop in
+    # the original Ranges with these points; the
+    # result must have at least one point since
+    # we know that s1 and s2 are in the Ranges
+    def _updated_range(r, first):
+        st = sign(r.step)*step
+        if r.start.is_finite:
+            rv = Range(first, r.stop, st)
+        else:
+            rv = Range(r.start, first + st, st)
+        return rv
+    r1 = _updated_range(a, s1)
+    r2 = _updated_range(b, s2)
+
+    # work with them both in the increasing direction
+    if sign(r1.step) < 0:
+        r1 = r1.reversed
+    if sign(r2.step) < 0:
+        r2 = r2.reversed
+
+    # return clipped Range with positive step; it
+    # can't be empty at this point
+    start = max(r1.start, r2.start)
+    stop = min(r1.stop, r2.stop)
+    return Range(start, stop, step)
+
+
+@intersection_sets.register(Range, Integers)
+def _(a, b):
+    return a
+
+
+@intersection_sets.register(Range, Rationals)
+def _(a, b):
+    return a
+
+
+@intersection_sets.register(ImageSet, Set)
+def _(self, other):
+    from sympy.solvers.diophantine import diophantine
+
+    # Only handle the straight-forward univariate case
+    if (len(self.lamda.variables) > 1
+            or self.lamda.signature != self.lamda.variables):
+        return None
+    base_set = self.base_sets[0]
+
+    # Intersection between ImageSets with Integers as base set
+    # For {f(n) : n in Integers} & {g(m) : m in Integers} we solve the
+    # diophantine equations f(n)=g(m).
+    # If the solutions for n are {h(t) : t in Integers} then we return
+    # {f(h(t)) : t in integers}.
+    # If the solutions for n are {n_1, n_2, ..., n_k} then we return
+    # {f(n_i) : 1 <= i <= k}.
+    if base_set is S.Integers:
+        gm = None
+        if isinstance(other, ImageSet) and other.base_sets == (S.Integers,):
+            gm = other.lamda.expr
+            var = other.lamda.variables[0]
+            # Symbol of second ImageSet lambda must be distinct from first
+            m = Dummy('m')
+            gm = gm.subs(var, m)
+        elif other is S.Integers:
+            m = gm = Dummy('m')
+        if gm is not None:
+            fn = self.lamda.expr
+            n = self.lamda.variables[0]
+            try:
+                solns = list(diophantine(fn - gm, syms=(n, m), permute=True))
+            except (TypeError, NotImplementedError):
+                # TypeError if equation not polynomial with rational coeff.
+                # NotImplementedError if correct format but no solver.
+                return
+            # 3 cases are possible for solns:
+            # - empty set,
+            # - one or more parametric (infinite) solutions,
+            # - a finite number of (non-parametric) solution couples.
+            # Among those, there is one type of solution set that is
+            # not helpful here: multiple parametric solutions.
+            if len(solns) == 0:
+                return S.EmptySet
+            elif any(s.free_symbols for tupl in solns for s in tupl):
+                if len(solns) == 1:
+                    soln, solm = solns[0]
+                    (t,) = soln.free_symbols
+                    expr = fn.subs(n, soln.subs(t, n)).expand()
+                    return imageset(Lambda(n, expr), S.Integers)
+                else:
+                    return
+            else:
+                return FiniteSet(*(fn.subs(n, s[0]) for s in solns))
+
+    if other == S.Reals:
+        from sympy.solvers.solvers import denoms, solve_linear
+
+        def _solution_union(exprs, sym):
+            # return a union of linear solutions to i in expr;
+            # if i cannot be solved, use a ConditionSet for solution
+            sols = []
+            for i in exprs:
+                x, xis = solve_linear(i, 0, [sym])
+                if x == sym:
+                    sols.append(FiniteSet(xis))
+                else:
+                    sols.append(ConditionSet(sym, Eq(i, 0)))
+            return Union(*sols)
+
+        f = self.lamda.expr
+        n = self.lamda.variables[0]
+
+        n_ = Dummy(n.name, real=True)
+        f_ = f.subs(n, n_)
+
+        re, im = f_.as_real_imag()
+        im = expand_complex(im)
+
+        re = re.subs(n_, n)
+        im = im.subs(n_, n)
+        ifree = im.free_symbols
+        lam = Lambda(n, re)
+        if im.is_zero:
+            # allow re-evaluation
+            # of self in this case to make
+            # the result canonical
+            pass
+        elif im.is_zero is False:
+            return S.EmptySet
+        elif ifree != {n}:
+            return None
+        else:
+            # univarite imaginary part in same variable;
+            # use numer instead of as_numer_denom to keep
+            # this as fast as possible while still handling
+            # simple cases
+            base_set &= _solution_union(
+                Mul.make_args(numer(im)), n)
+        # exclude values that make denominators 0
+        base_set -= _solution_union(denoms(f), n)
+        return imageset(lam, base_set)
+
+    elif isinstance(other, Interval):
+        from sympy.solvers.solveset import (invert_real, invert_complex,
+                                            solveset)
+
+        f = self.lamda.expr
+        n = self.lamda.variables[0]
+        new_inf, new_sup = None, None
+        new_lopen, new_ropen = other.left_open, other.right_open
+
+        if f.is_real:
+            inverter = invert_real
+        else:
+            inverter = invert_complex
+
+        g1, h1 = inverter(f, other.inf, n)
+        g2, h2 = inverter(f, other.sup, n)
+
+        if all(isinstance(i, FiniteSet) for i in (h1, h2)):
+            if g1 == n:
+                if len(h1) == 1:
+                    new_inf = h1.args[0]
+            if g2 == n:
+                if len(h2) == 1:
+                    new_sup = h2.args[0]
+            # TODO: Design a technique to handle multiple-inverse
+            # functions
+
+            # Any of the new boundary values cannot be determined
+            if any(i is None for i in (new_sup, new_inf)):
+                return
+
+
+            range_set = S.EmptySet
+
+            if all(i.is_real for i in (new_sup, new_inf)):
+                # this assumes continuity of underlying function
+                # however fixes the case when it is decreasing
+                if new_inf > new_sup:
+                    new_inf, new_sup = new_sup, new_inf
+                new_interval = Interval(new_inf, new_sup, new_lopen, new_ropen)
+                range_set = base_set.intersect(new_interval)
+            else:
+                if other.is_subset(S.Reals):
+                    solutions = solveset(f, n, S.Reals)
+                    if not isinstance(range_set, (ImageSet, ConditionSet)):
+                        range_set = solutions.intersect(other)
+                    else:
+                        return
+
+            if range_set is S.EmptySet:
+                return S.EmptySet
+            elif isinstance(range_set, Range) and range_set.size is not S.Infinity:
+                range_set = FiniteSet(*list(range_set))
+
+            if range_set is not None:
+                return imageset(Lambda(n, f), range_set)
+            return
+        else:
+            return
+
+
+@intersection_sets.register(ProductSet, ProductSet)
+def _(a, b):
+    if len(b.args) != len(a.args):
+        return S.EmptySet
+    return ProductSet(*(i.intersect(j) for i, j in zip(a.sets, b.sets)))
+
+
+@intersection_sets.register(Interval, Interval)
+def _(a, b):
+    # handle (-oo, oo)
+    infty = S.NegativeInfinity, S.Infinity
+    if a == Interval(*infty):
+        l, r = a.left, a.right
+        if l.is_real or l in infty or r.is_real or r in infty:
+            return b
+
+    # We can't intersect [0,3] with [x,6] -- we don't know if x>0 or x<0
+    if not a._is_comparable(b):
+        return None
+
+    empty = False
+
+    if a.start <= b.end and b.start <= a.end:
+        # Get topology right.
+        if a.start < b.start:
+            start = b.start
+            left_open = b.left_open
+        elif a.start > b.start:
+            start = a.start
+            left_open = a.left_open
+        else:
+            start = a.start
+            if not _aresame(a.start, b.start):
+                # For example Integer(2) != Float(2)
+                # Prefer the Float boundary because Floats should be
+                # contagious in calculations.
+                if b.start.has(Float) and not a.start.has(Float):
+                    start = b.start
+                elif a.start.has(Float) and not b.start.has(Float):
+                    start = a.start
+                else:
+                    #this is to ensure that if Eq(a.start, b.start) but
+                    #type(a.start) != type(b.start) the order of a and b
+                    #does not matter for the result
+                    start = list(ordered([a,b]))[0].start
+            left_open = a.left_open or b.left_open
+
+        if a.end < b.end:
+            end = a.end
+            right_open = a.right_open
+        elif a.end > b.end:
+            end = b.end
+            right_open = b.right_open
+        else:
+            # see above for logic with start
+            end = a.end
+            if not _aresame(a.end, b.end):
+                if b.end.has(Float) and not a.end.has(Float):
+                    end = b.end
+                elif a.end.has(Float) and not b.end.has(Float):
+                    end = a.end
+                else:
+                    end = list(ordered([a,b]))[0].end
+            right_open = a.right_open or b.right_open
+
+        if end - start == 0 and (left_open or right_open):
+            empty = True
+    else:
+        empty = True
+
+    if empty:
+        return S.EmptySet
+
+    return Interval(start, end, left_open, right_open)
+
+@intersection_sets.register(EmptySet, Set)
+def _(a, b):
+    return S.EmptySet
+
+@intersection_sets.register(UniversalSet, Set)
+def _(a, b):
+    return b
+
+@intersection_sets.register(FiniteSet, FiniteSet)
+def _(a, b):
+    return FiniteSet(*(a._elements & b._elements))
+
+@intersection_sets.register(FiniteSet, Set)
+def _(a, b):
+    try:
+        return FiniteSet(*[el for el in a if el in b])
+    except TypeError:
+        return None  # could not evaluate `el in b` due to symbolic ranges.
+
+@intersection_sets.register(Set, Set)
+def _(a, b):
+    return None
+
+@intersection_sets.register(Integers, Rationals)
+def _(a, b):
+    return a
+
+@intersection_sets.register(Naturals, Rationals)
+def _(a, b):
+    return a
+
+@intersection_sets.register(Rationals, Reals)
+def _(a, b):
+    return a
+
+def _intlike_interval(a, b):
+    try:
+        if b._inf is S.NegativeInfinity and b._sup is S.Infinity:
+            return a
+        s = Range(max(a.inf, ceiling(b.left)), floor(b.right) + 1)
+        return intersection_sets(s, b)  # take out endpoints if open interval
+    except ValueError:
+        return None
+
+@intersection_sets.register(Integers, Interval)
+def _(a, b):
+    return _intlike_interval(a, b)
+
+@intersection_sets.register(Naturals, Interval)
+def _(a, b):
+    return _intlike_interval(a, b)

rl/Lib/site-packages/sympy/sets/handlers/issubset.py

@@ -0,0 +1,144 @@
+from sympy.core.singleton import S
+from sympy.core.symbol import Symbol
+from sympy.core.logic import fuzzy_and, fuzzy_bool, fuzzy_not, fuzzy_or
+from sympy.core.relational import Eq
+from sympy.sets.sets import FiniteSet, Interval, Set, Union, ProductSet
+from sympy.sets.fancysets import Complexes, Reals, Range, Rationals
+from sympy.multipledispatch import Dispatcher
+
+
+_inf_sets = [S.Naturals, S.Naturals0, S.Integers, S.Rationals, S.Reals, S.Complexes]
+
+
+is_subset_sets = Dispatcher('is_subset_sets')
+
+
+@is_subset_sets.register(Set, Set)
+def _(a, b):
+    return None
+
+@is_subset_sets.register(Interval, Interval)
+def _(a, b):
+    # This is correct but can be made more comprehensive...
+    if fuzzy_bool(a.start < b.start):
+        return False
+    if fuzzy_bool(a.end > b.end):
+        return False
+    if (b.left_open and not a.left_open and fuzzy_bool(Eq(a.start, b.start))):
+        return False
+    if (b.right_open and not a.right_open and fuzzy_bool(Eq(a.end, b.end))):
+        return False
+
+@is_subset_sets.register(Interval, FiniteSet)
+def _(a_interval, b_fs):
+    # An Interval can only be a subset of a finite set if it is finite
+    # which can only happen if it has zero measure.
+    if fuzzy_not(a_interval.measure.is_zero):
+        return False
+
+@is_subset_sets.register(Interval, Union)
+def _(a_interval, b_u):
+    if all(isinstance(s, (Interval, FiniteSet)) for s in b_u.args):
+        intervals = [s for s in b_u.args if isinstance(s, Interval)]
+        if all(fuzzy_bool(a_interval.start < s.start) for s in intervals):
+            return False
+        if all(fuzzy_bool(a_interval.end > s.end) for s in intervals):
+            return False
+        if a_interval.measure.is_nonzero:
+            no_overlap = lambda s1, s2: fuzzy_or([
+                    fuzzy_bool(s1.end <= s2.start),
+                    fuzzy_bool(s1.start >= s2.end),
+                    ])
+            if all(no_overlap(s, a_interval) for s in intervals):
+                return False
+
+@is_subset_sets.register(Range, Range)
+def _(a, b):
+    if a.step == b.step == 1:
+        return fuzzy_and([fuzzy_bool(a.start >= b.start),
+                          fuzzy_bool(a.stop <= b.stop)])
+
+@is_subset_sets.register(Range, Interval)
+def _(a_range, b_interval):
+    if a_range.step.is_positive:
+        if b_interval.left_open and a_range.inf.is_finite:
+            cond_left = a_range.inf > b_interval.left
+        else:
+            cond_left = a_range.inf >= b_interval.left
+        if b_interval.right_open and a_range.sup.is_finite:
+            cond_right = a_range.sup < b_interval.right
+        else:
+            cond_right = a_range.sup <= b_interval.right
+        return fuzzy_and([cond_left, cond_right])
+
+@is_subset_sets.register(Range, FiniteSet)
+def _(a_range, b_finiteset):
+    try:
+        a_size = a_range.size
+    except ValueError:
+        # symbolic Range of unknown size
+        return None
+    if a_size > len(b_finiteset):
+        return False
+    elif any(arg.has(Symbol) for arg in a_range.args):
+        return fuzzy_and(b_finiteset.contains(x) for x in a_range)
+    else:
+        # Checking A \ B == EmptySet is more efficient than repeated naive
+        # membership checks on an arbitrary FiniteSet.
+        a_set = set(a_range)
+        b_remaining = len(b_finiteset)
+        # Symbolic expressions and numbers of unknown type (integer or not) are
+        # all counted as "candidates", i.e. *potentially* matching some a in
+        # a_range.
+        cnt_candidate = 0
+        for b in b_finiteset:
+            if b.is_Integer:
+                a_set.discard(b)
+            elif fuzzy_not(b.is_integer):
+                pass
+            else:
+                cnt_candidate += 1
+            b_remaining -= 1
+            if len(a_set) > b_remaining + cnt_candidate:
+                return False
+            if len(a_set) == 0:
+                return True
+        return None
+
+@is_subset_sets.register(Interval, Range)
+def _(a_interval, b_range):
+    if a_interval.measure.is_extended_nonzero:
+        return False
+
+@is_subset_sets.register(Interval, Rationals)
+def _(a_interval, b_rationals):
+    if a_interval.measure.is_extended_nonzero:
+        return False
+
+@is_subset_sets.register(Range, Complexes)
+def _(a, b):
+    return True
+
+@is_subset_sets.register(Complexes, Interval)
+def _(a, b):
+    return False
+
+@is_subset_sets.register(Complexes, Range)
+def _(a, b):
+    return False
+
+@is_subset_sets.register(Complexes, Rationals)
+def _(a, b):
+    return False
+
+@is_subset_sets.register(Rationals, Reals)
+def _(a, b):
+    return True
+
+@is_subset_sets.register(Rationals, Range)
+def _(a, b):
+    return False
+
+@is_subset_sets.register(ProductSet, FiniteSet)
+def _(a_ps, b_fs):
+    return fuzzy_and(b_fs.contains(x) for x in a_ps)

rl/Lib/site-packages/sympy/sets/handlers/mul.py

@@ -0,0 +1,79 @@
+from sympy.core import Basic, Expr
+from sympy.core.numbers import oo
+from sympy.core.symbol import symbols
+from sympy.multipledispatch import Dispatcher
+from sympy.sets.setexpr import set_mul
+from sympy.sets.sets import Interval, Set
+
+
+_x, _y = symbols("x y")
+
+
+_set_mul = Dispatcher('_set_mul')
+_set_div = Dispatcher('_set_div')
+
+
+@_set_mul.register(Basic, Basic)
+def _(x, y):
+    return None
+
+@_set_mul.register(Set, Set)
+def _(x, y):
+    return None
+
+@_set_mul.register(Expr, Expr)
+def _(x, y):
+    return x*y
+
+@_set_mul.register(Interval, Interval)
+def _(x, y):
+    """
+    Multiplications in interval arithmetic
+    https://en.wikipedia.org/wiki/Interval_arithmetic
+    """
+    # TODO: some intervals containing 0 and oo will fail as 0*oo returns nan.
+    comvals = (
+        (x.start * y.start, bool(x.left_open or y.left_open)),
+        (x.start * y.end, bool(x.left_open or y.right_open)),
+        (x.end * y.start, bool(x.right_open or y.left_open)),
+        (x.end * y.end, bool(x.right_open or y.right_open)),
+    )
+    # TODO: handle symbolic intervals
+    minval, minopen = min(comvals)
+    maxval, maxopen = max(comvals)
+    return Interval(
+        minval,
+        maxval,
+        minopen,
+        maxopen
+    )
+
+@_set_div.register(Basic, Basic)
+def _(x, y):
+    return None
+
+@_set_div.register(Expr, Expr)
+def _(x, y):
+    return x/y
+
+@_set_div.register(Set, Set)
+def _(x, y):
+    return None
+
+@_set_div.register(Interval, Interval)
+def _(x, y):
+    """
+    Divisions in interval arithmetic
+    https://en.wikipedia.org/wiki/Interval_arithmetic
+    """
+    if (y.start*y.end).is_negative:
+        return Interval(-oo, oo)
+    if y.start == 0:
+        s2 = oo
+    else:
+        s2 = 1/y.start
+    if y.end == 0:
+        s1 = -oo
+    else:
+        s1 = 1/y.end
+    return set_mul(x, Interval(s1, s2, y.right_open, y.left_open))

rl/Lib/site-packages/sympy/sets/handlers/power.py

@@ -0,0 +1,107 @@
+from sympy.core import Basic, Expr
+from sympy.core.function import Lambda
+from sympy.core.numbers import oo, Infinity, NegativeInfinity, Zero, Integer
+from sympy.core.singleton import S
+from sympy.core.symbol import symbols
+from sympy.functions.elementary.miscellaneous import (Max, Min)
+from sympy.sets.fancysets import ImageSet
+from sympy.sets.setexpr import set_div
+from sympy.sets.sets import Set, Interval, FiniteSet, Union
+from sympy.multipledispatch import Dispatcher
+
+
+_x, _y = symbols("x y")
+
+
+_set_pow = Dispatcher('_set_pow')
+
+
+@_set_pow.register(Basic, Basic)
+def _(x, y):
+    return None
+
+@_set_pow.register(Set, Set)
+def _(x, y):
+    return ImageSet(Lambda((_x, _y), (_x ** _y)), x, y)
+
+@_set_pow.register(Expr, Expr)
+def _(x, y):
+    return x**y
+
+@_set_pow.register(Interval, Zero)
+def _(x, z):
+    return FiniteSet(S.One)
+
+@_set_pow.register(Interval, Integer)
+def _(x, exponent):
+    """
+    Powers in interval arithmetic
+    https://en.wikipedia.org/wiki/Interval_arithmetic
+    """
+    s1 = x.start**exponent
+    s2 = x.end**exponent
+    if ((s2 > s1) if exponent > 0 else (x.end > -x.start)) == True:
+        left_open = x.left_open
+        right_open = x.right_open
+        # TODO: handle unevaluated condition.
+        sleft = s2
+    else:
+        # TODO: `s2 > s1` could be unevaluated.
+        left_open = x.right_open
+        right_open = x.left_open
+        sleft = s1
+
+    if x.start.is_positive:
+        return Interval(
+            Min(s1, s2),
+            Max(s1, s2), left_open, right_open)
+    elif x.end.is_negative:
+        return Interval(
+            Min(s1, s2),
+            Max(s1, s2), left_open, right_open)
+
+    # Case where x.start < 0 and x.end > 0:
+    if exponent.is_odd:
+        if exponent.is_negative:
+            if x.start.is_zero:
+                return Interval(s2, oo, x.right_open)
+            if x.end.is_zero:
+                return Interval(-oo, s1, True, x.left_open)
+            return Union(Interval(-oo, s1, True, x.left_open), Interval(s2, oo, x.right_open))
+        else:
+            return Interval(s1, s2, x.left_open, x.right_open)
+    elif exponent.is_even:
+        if exponent.is_negative:
+            if x.start.is_zero:
+                return Interval(s2, oo, x.right_open)
+            if x.end.is_zero:
+                return Interval(s1, oo, x.left_open)
+            return Interval(0, oo)
+        else:
+            return Interval(S.Zero, sleft, S.Zero not in x, left_open)
+
+@_set_pow.register(Interval, Infinity)
+def _(b, e):
+    # TODO: add logic for open intervals?
+    if b.start.is_nonnegative:
+        if b.end < 1:
+            return FiniteSet(S.Zero)
+        if b.start > 1:
+            return FiniteSet(S.Infinity)
+        return Interval(0, oo)
+    elif b.end.is_negative:
+        if b.start > -1:
+            return FiniteSet(S.Zero)
+        if b.end < -1:
+            return FiniteSet(-oo, oo)
+        return Interval(-oo, oo)
+    else:
+        if b.start > -1:
+            if b.end < 1:
+                return FiniteSet(S.Zero)
+            return Interval(0, oo)
+        return Interval(-oo, oo)
+
+@_set_pow.register(Interval, NegativeInfinity)
+def _(b, e):
+    return _set_pow(set_div(S.One, b), oo)

rl/Lib/site-packages/sympy/sets/handlers/union.py

@@ -0,0 +1,147 @@
+from sympy.core.singleton import S
+from sympy.core.sympify import sympify
+from sympy.functions.elementary.miscellaneous import Min, Max
+from sympy.sets.sets import (EmptySet, FiniteSet, Intersection,
+    Interval, ProductSet, Set, Union, UniversalSet)
+from sympy.sets.fancysets import (ComplexRegion, Naturals, Naturals0,
+    Integers, Rationals, Reals)
+from sympy.multipledispatch import Dispatcher
+
+
+union_sets = Dispatcher('union_sets')
+
+
+@union_sets.register(Naturals0, Naturals)
+def _(a, b):
+    return a
+
+@union_sets.register(Rationals, Naturals)
+def _(a, b):
+    return a
+
+@union_sets.register(Rationals, Naturals0)
+def _(a, b):
+    return a
+
+@union_sets.register(Reals, Naturals)
+def _(a, b):
+    return a
+
+@union_sets.register(Reals, Naturals0)
+def _(a, b):
+    return a
+
+@union_sets.register(Reals, Rationals)
+def _(a, b):
+    return a
+
+@union_sets.register(Integers, Set)
+def _(a, b):
+    intersect = Intersection(a, b)
+    if intersect == a:
+        return b
+    elif intersect == b:
+        return a
+
+@union_sets.register(ComplexRegion, Set)
+def _(a, b):
+    if b.is_subset(S.Reals):
+        # treat a subset of reals as a complex region
+        b = ComplexRegion.from_real(b)
+
+    if b.is_ComplexRegion:
+        # a in rectangular form
+        if (not a.polar) and (not b.polar):
+            return ComplexRegion(Union(a.sets, b.sets))
+        # a in polar form
+        elif a.polar and b.polar:
+            return ComplexRegion(Union(a.sets, b.sets), polar=True)
+    return None
+
+@union_sets.register(EmptySet, Set)
+def _(a, b):
+    return b
+
+
+@union_sets.register(UniversalSet, Set)
+def _(a, b):
+    return a
+
+@union_sets.register(ProductSet, ProductSet)
+def _(a, b):
+    if b.is_subset(a):
+        return a
+    if len(b.sets) != len(a.sets):
+        return None
+    if len(a.sets) == 2:
+        a1, a2 = a.sets
+        b1, b2 = b.sets
+        if a1 == b1:
+            return a1 * Union(a2, b2)
+        if a2 == b2:
+            return Union(a1, b1) * a2
+    return None
+
+@union_sets.register(ProductSet, Set)
+def _(a, b):
+    if b.is_subset(a):
+        return a
+    return None
+
+@union_sets.register(Interval, Interval)
+def _(a, b):
+    if a._is_comparable(b):
+        # Non-overlapping intervals
+        end = Min(a.end, b.end)
+        start = Max(a.start, b.start)
+        if (end < start or
+           (end == start and (end not in a and end not in b))):
+            return None
+        else:
+            start = Min(a.start, b.start)
+            end = Max(a.end, b.end)
+
+            left_open = ((a.start != start or a.left_open) and
+                         (b.start != start or b.left_open))
+            right_open = ((a.end != end or a.right_open) and
+                          (b.end != end or b.right_open))
+            return Interval(start, end, left_open, right_open)
+
+@union_sets.register(Interval, UniversalSet)
+def _(a, b):
+    return S.UniversalSet
+
+@union_sets.register(Interval, Set)
+def _(a, b):
+    # If I have open end points and these endpoints are contained in b
+    # But only in case, when endpoints are finite. Because
+    # interval does not contain oo or -oo.
+    open_left_in_b_and_finite = (a.left_open and
+                                     sympify(b.contains(a.start)) is S.true and
+                                     a.start.is_finite)
+    open_right_in_b_and_finite = (a.right_open and
+                                      sympify(b.contains(a.end)) is S.true and
+                                      a.end.is_finite)
+    if open_left_in_b_and_finite or open_right_in_b_and_finite:
+        # Fill in my end points and return
+        open_left = a.left_open and a.start not in b
+        open_right = a.right_open and a.end not in b
+        new_a = Interval(a.start, a.end, open_left, open_right)
+        return {new_a, b}
+    return None
+
+@union_sets.register(FiniteSet, FiniteSet)
+def _(a, b):
+    return FiniteSet(*(a._elements | b._elements))
+
+@union_sets.register(FiniteSet, Set)
+def _(a, b):
+    # If `b` set contains one of my elements, remove it from `a`
+    if any(b.contains(x) == True for x in a):
+        return {
+            FiniteSet(*[x for x in a if b.contains(x) != True]), b}
+    return None
+
+@union_sets.register(Set, Set)
+def _(a, b):
+    return None