def test_reduce_poly_inequalities_real_relational():
x = Symbol('x', real=True)
y = Symbol('y', real=True)
assert reduce_rational_inequalities([[Eq(x**2, 0)]], x,
relational=True) == Eq(x, 0)
assert reduce_rational_inequalities([[Le(x**2, 0)]], x,
relational=True) == Eq(x, 0)
assert reduce_rational_inequalities([[Lt(x**2, 0)]], x,
relational=True) == False
assert reduce_rational_inequalities([[Ge(x**2, 0)]], x,
relational=True) == And(
Lt(-oo, x), Lt(x, oo))
assert reduce_rational_inequalities([[Gt(x**2, 0)]], x,
relational=True) == Or(
And(Lt(-oo, x), Lt(x, 0)),
And(Lt(0, x), Lt(x, oo)))
assert reduce_rational_inequalities([[Ne(x**2, 0)]], x,
relational=True) == Or(
And(Lt(-oo, x), Lt(x, 0)),
And(Lt(0, x), Lt(x, oo)))
assert reduce_rational_inequalities([[Eq(x**2, 1)]], x,
relational=True) == Or(
Eq(x, -1), Eq(x, 1))
assert reduce_rational_inequalities([[Le(x**2, 1)]], x,
relational=True) == And(
Le(-1, x), Le(x, 1))
assert reduce_rational_inequalities([[Lt(x**2, 1)]], x,
relational=True) == And(
Lt(-1, x), Lt(x, 1))
assert reduce_rational_inequalities([[Ge(x**2, 1)]], x,
relational=True) == Or(
And(Le(1, x), Lt(x, oo)),
And(Le(x, -1), Lt(-oo, x)))
assert reduce_rational_inequalities([[Gt(x**2, 1)]], x,
relational=True) == Or(
And(Lt(1, x), Lt(x, oo)),
And(Lt(x, -1), Lt(-oo, x)))
assert reduce_rational_inequalities([[Ne(x**2, 1)]], x,
relational=True) == Or(
And(Lt(-oo, x), Lt(x, -1)),
And(Lt(-1, x), Lt(x, 1)),
And(Lt(1, x), Lt(x, oo)))
assert reduce_rational_inequalities([[Le(x**2, 1.0)]], x,
relational=True) == And(
Le(-1.0, x), Le(x, 1.0))
assert reduce_rational_inequalities([[Lt(x**2, 1.0)]], x,
relational=True) == And(
Lt(-1.0, x), Lt(x, 1.0))
assert reduce_rational_inequalities([[Ge(x**2, 1.0)]], x,
relational=True) == Or(
And(Lt(Float('-inf'), x),
Le(x, -1.0)),
And(Le(1.0, x),
Lt(x, Float('+inf'))))
assert reduce_rational_inequalities([[Gt(x**2, 1.0)]], x,
relational=True) == Or(
And(Lt(Float('-inf'), x),
Lt(x, -1.0)),
And(Lt(1.0, x),
Lt(x, Float('+inf'))))
assert reduce_rational_inequalities([[Ne(x**2, 1.0)]], x, relational=True) == \
Or(And(Lt(-1.0, x), Lt(x, 1.0)), And(Lt(Float('-inf'), x), Lt(x, -1.0)),
And(Lt(1.0, x), Lt(x, Float('+inf'))))
def test_issue_11045():
assert integrate(1 / (x * sqrt(x**2 - 1)), (x, 1, 2)) == pi / 3
# handle And with Or arguments
assert Piecewise((1, And(Or(x < 1, x > 3), x < 2)), (0, True)).integrate(
(x, 0, 3)) == 1
# hidden false
assert Piecewise((1, x > 1), (2, x > x + 1), (3, True)).integrate(
(x, 0, 3)) == 5
# targetcond is Eq
assert Piecewise((1, x > 1), (2, Eq(1, x)), (3, True)).integrate(
(x, 0, 4)) == 6
# And has Relational needing to be solved
assert Piecewise((1, And(2 * x > x + 1, x < 2)), (0, True)).integrate(
(x, 0, 3)) == 1
# Or has Relational needing to be solved
assert Piecewise((1, Or(2 * x > x + 2, x < 1)), (0, True)).integrate(
(x, 0, 3)) == 2
# ignore hidden false (handled in canonicalization)
assert Piecewise((1, x > 1), (2, x > x + 1), (3, True)).integrate(
(x, 0, 3)) == 5
# watch for hidden True Piecewise
assert Piecewise((2, Eq(1 - x, x * (1 / x - 1))), (0, True)).integrate(
(x, 0, 3)) == 6
# overlapping conditions of targetcond are recognized and ignored;
# the condition x > 3 will be pre-empted by the first condition
assert Piecewise((1, Or(x < 1, x > 2)), (2, x > 3), (3, True)).integrate(
(x, 0, 4)) == 6
# convert Ne to Or
assert Piecewise((1, Ne(x, 0)), (2, True)).integrate((x, -1, 1)) == 2
# no default but well defined
assert Piecewise((x, (x > 1) & (x < 3)), (1, (x < 4))).integrate(
(x, 1, 4)) == 5
p = Piecewise((x, (x > 1) & (x < 3)), (1, (x < 4)))
nan = Undefined
i = p.integrate((x, 1, y))
assert i == Piecewise(
(y - 1, y < 1),
(Min(3, y)**2 / 2 - Min(3, y) + Min(4, y) - 1 / 2, y <= Min(4, y)),
(nan, True))
assert p.integrate((x, 1, -1)) == i.subs(y, -1)
assert p.integrate((x, 1, 4)) == 5
assert p.integrate((x, 1, 5)) == nan
# handle Not
p = Piecewise((1, x > 1), (2, Not(And(x > 1, x < 3))), (3, True))
assert p.integrate((x, 0, 3)) == 4
# handle updating of int_expr when there is overlap
p = Piecewise((1, And(5 > x, x > 1)), (2, Or(x < 3, x > 7)), (4, x < 8))
assert p.integrate((x, 0, 10)) == 20
# And with Eq arg handling
assert Piecewise((1, x < 1), (2, And(Eq(x, 3), x > 1))).integrate(
(x, 0, 3)) == S.NaN
assert Piecewise((1, x < 1), (2, And(Eq(x, 3), x > 1)),
(3, True)).integrate((x, 0, 3)) == 7
assert Piecewise((1, x < 0), (2, And(Eq(x, 3), x < 1)),
(3, True)).integrate((x, -1, 1)) == 4
# middle condition doesn't matter: it's a zero width interval
assert Piecewise((1, x < 1), (2, Eq(x, 3) & (y < x)), (3, True)).integrate(
(x, 0, 3)) == 7
def test_reduce_inequalities_multivariate():
assert reduce_inequalities([Ge(x**2, 1), Ge(y**2, 1)]) == And(
Or(And(Le(S.One, x), Lt(x, oo)), And(Le(x, -1), Lt(-oo, x))),
Or(And(Le(S.One, y), Lt(y, oo)), And(Le(y, -1), Lt(-oo, y))))
def test_piecewise():
# Test canonization
assert Piecewise((x, x < 1), (0, True)) == Piecewise((x, x < 1), (0, True))
assert Piecewise((x, x < 1), (0, True), (1, True)) == \
Piecewise((x, x < 1), (0, True))
assert Piecewise((x, x < 1), (0, False), (-1, 1 > 2)) == \
Piecewise((x, x < 1))
assert Piecewise((x, x < 1), (0, x < 1), (0, True)) == \
Piecewise((x, x < 1), (0, True))
assert Piecewise((x, x < 1), (0, x < 2), (0, True)) == \
Piecewise((x, x < 1), (0, True))
assert Piecewise((x, x < 1), (x, x < 2), (0, True)) == \
Piecewise((x, Or(x < 1, x < 2)), (0, True))
assert Piecewise((x, x < 1), (x, x < 2), (x, True)) == x
assert Piecewise((x, True)) == x
raises(TypeError, lambda: Piecewise(x))
raises(TypeError, lambda: Piecewise((x, x**2)))
# Test subs
p = Piecewise((-1, x < -1), (x**2, x < 0), (log(x), x >= 0))
p_x2 = Piecewise((-1, x**2 < -1), (x**4, x**2 < 0), (log(x**2), x**2 >= 0))
assert p.subs(x, x**2) == p_x2
assert p.subs(x, -5) == -1
assert p.subs(x, -1) == 1
assert p.subs(x, 1) == log(1)
# More subs tests
p2 = Piecewise((1, x < pi), (-1, x < 2 * pi), (0, x > 2 * pi))
p3 = Piecewise((1, Eq(x, 0)), (1 / x, True))
p4 = Piecewise((1, Eq(x, 0)), (2, 1 / x > 2))
assert p2.subs(x, 2) == 1
assert p2.subs(x, 4) == -1
assert p2.subs(x, 10) == 0
assert p3.subs(x, 0.0) == 1
assert p4.subs(x, 0.0) == 1
f, g, h = symbols('f,g,h', cls=Function)
pf = Piecewise((f(x), x < -1), (f(x) + h(x) + 2, x <= 1))
pg = Piecewise((g(x), x < -1), (g(x) + h(x) + 2, x <= 1))
assert pg.subs(g, f) == pf
assert Piecewise((1, Eq(x, 0)), (0, True)).subs(x, 0) == 1
assert Piecewise((1, Eq(x, 0)), (0, True)).subs(x, 1) == 0
assert Piecewise((1, Eq(x, y)), (0, True)).subs(x, y) == 1
assert Piecewise((1, Eq(x, z)), (0, True)).subs(x, z) == 1
assert Piecewise((1, Eq(exp(x), cos(z))), (0, True)).subs(x, z) == \
Piecewise((1, Eq(exp(z), cos(z))), (0, True))
assert Piecewise((1, Eq(x, y * (y + 1))), (0, True)).subs(x, y**2 + y) == 1
p5 = Piecewise((0, Eq(cos(x) + y, 0)), (1, True))
assert p5.subs(y, 0) == Piecewise((0, Eq(cos(x), 0)), (1, True))
# Test evalf
assert p.evalf() == p
assert p.evalf(subs={x: -2}) == -1
assert p.evalf(subs={x: -1}) == 1
assert p.evalf(subs={x: 1}) == log(1)
# Test doit
f_int = Piecewise((Integral(x, (x, 0, 1)), x < 1))
assert f_int.doit() == Piecewise((1.0 / 2.0, x < 1))
# Test differentiation
f = x
fp = x * p
dp = Piecewise((0, x < -1), (2 * x, x < 0), (1 / x, x >= 0))
fp_dx = x * dp + p
assert diff(p, x) == dp
assert diff(f * p, x) == fp_dx
# Test simple arithmetic
assert x * p == fp
assert x * p + p == p + x * p
assert p + f == f + p
assert p + dp == dp + p
assert p - dp == -(dp - p)
# Test power
dp2 = Piecewise((0, x < -1), (4 * x**2, x < 0), (1 / x**2, x >= 0))
assert dp**2 == dp2
# Test _eval_interval
f1 = x * y + 2
f2 = x * y**2 + 3
peval = Piecewise((f1, x < 0), (f2, x > 0))
peval_interval = f1.subs(x, 0) - f1.subs(x, -1) + f2.subs(x, 1) - f2.subs(
x, 0)
assert peval._eval_interval(x, 0, 0) == 0
assert peval._eval_interval(x, -1, 1) == peval_interval
peval2 = Piecewise((f1, x < 0), (f2, True))
assert peval2._eval_interval(x, 0, 0) == 0
assert peval2._eval_interval(x, 1, -1) == -peval_interval
assert peval2._eval_interval(x, -1, -2) == f1.subs(x, -2) - f1.subs(x, -1)
assert peval2._eval_interval(x, -1, 1) == peval_interval
assert peval2._eval_interval(x, None, 0) == peval2.subs(x, 0)
assert peval2._eval_interval(x, -1, None) == -peval2.subs(x, -1)
# Test integration
p_int = Piecewise((-x, x < -1), (x**3 / 3.0, x < 0),
(-x + x * log(x), x >= 0))
assert integrate(p, x) == p_int
p = Piecewise((x, x < 1), (x**2, -1 <= x), (x, 3 < x))
assert integrate(p, (x, -2, 2)) == 5.0 / 6.0
assert integrate(p, (x, 2, -2)) == -5.0 / 6.0
p = Piecewise((0, x < 0), (1, x < 1), (0, x < 2), (1, x < 3), (0, True))
assert integrate(p, (x, -oo, oo)) == 2
p = Piecewise((x, x < -10), (x**2, x <= -1), (x, 1 < x))
raises(ValueError, lambda: integrate(p, (x, -2, 2)))
# Test commutativity
assert p.is_commutative is True
def test_Or():
N = Normal('N', 0, 1)
assert simplify(P(Or(N > 2, N < 1))) == \
-erf(sqrt(2))/2 - erfc(sqrt(2)/2)/2 + S(3)/2
assert P(Or(N < 0, N < 1)) == P(N < 1)
assert P(Or(N > 0, N < 0)) == 1
def test_count_ops_visual():
ADD, MUL, POW, SIN, COS, EXP, AND, D, G = symbols(
'Add Mul Pow sin cos exp And Derivative Integral'.upper())
DIV, SUB, NEG = symbols('DIV SUB NEG')
NOT, OR, AND, XOR, IMPLIES, EQUIVALENT, ITE, BASIC, TUPLE = symbols(
'Not Or And Xor Implies Equivalent ITE Basic Tuple'.upper())
def count(val):
return count_ops(val, visual=True)
assert count(7) is S.Zero
assert count(S(7)) is S.Zero
assert count(-1) == NEG
assert count(-2) == NEG
assert count(S(2) / 3) == DIV
assert count(pi / 3) == DIV
assert count(-pi / 3) == DIV + NEG
assert count(I - 1) == SUB
assert count(1 - I) == SUB
assert count(1 - 2 * I) == SUB + MUL
assert count(x) is S.Zero
assert count(-x) == NEG
assert count(-2 * x / 3) == NEG + DIV + MUL
assert count(1 / x) == DIV
assert count(1 / (x * y)) == DIV + MUL
assert count(-1 / x) == NEG + DIV
assert count(-2 / x) == NEG + DIV
assert count(x / y) == DIV
assert count(-x / y) == NEG + DIV
assert count(x**2) == POW
assert count(-x**2) == POW + NEG
assert count(-2 * x**2) == POW + MUL + NEG
assert count(x + pi / 3) == ADD + DIV
assert count(x + S(1) / 3) == ADD + DIV
assert count(x + y) == ADD
assert count(x - y) == SUB
assert count(y - x) == SUB
assert count(-1 / (x - y)) == DIV + NEG + SUB
assert count(-1 / (y - x)) == DIV + NEG + SUB
assert count(1 + x**y) == ADD + POW
assert count(1 + x + y) == 2 * ADD
assert count(1 + x + y + z) == 3 * ADD
assert count(1 + x**y + 2 * x * y + y**2) == 3 * ADD + 2 * POW + 2 * MUL
assert count(2 * z + y + x + 1) == 3 * ADD + MUL
assert count(2 * z + y**17 + x + 1) == 3 * ADD + MUL + POW
assert count(2 * z + y**17 + x + sin(x)) == 3 * ADD + POW + MUL + SIN
assert count(2 * z + y**17 + x +
sin(x**2)) == 3 * ADD + MUL + 2 * POW + SIN
assert count(2 * z + y**17 + x + sin(x**2) +
exp(cos(x))) == 4 * ADD + MUL + 2 * POW + EXP + COS + SIN
assert count(Derivative(x, x)) == D
assert count(Integral(x, x) + 2 * x / (1 + x)) == G + DIV + MUL + 2 * ADD
assert count(Basic()) is S.Zero
assert count({x + 1: sin(x)}) == ADD + SIN
assert count([x + 1, sin(x) + y, None]) == ADD + SIN + ADD
assert count({x + 1: sin(x), y: cos(x) + 1}) == SIN + COS + 2 * ADD
assert count({}) is S.Zero
assert count([x + 1, sin(x) * y, None]) == SIN + ADD + MUL
assert count([]) is S.Zero
assert count(Basic()) == 0
assert count(Basic(Basic(), Basic(x, x + y))) == ADD + 2 * BASIC
assert count(Basic(x, x + y)) == ADD + BASIC
assert count(Or(x, y)) == OR
assert count(And(x, y)) == AND
assert count(And(x**y, z)) == AND + POW
assert count(Or(x, Or(y, And(z, a)))) == AND + OR
assert count(Nor(x, y)) == NOT + OR
assert count(Nand(x, y)) == NOT + AND
assert count(Xor(x, y)) == XOR
assert count(Implies(x, y)) == IMPLIES
assert count(Equivalent(x, y)) == EQUIVALENT
assert count(ITE(x, y, z)) == ITE
assert count([Or(x, y), And(x, y), Basic(x + y)]) == ADD + AND + BASIC + OR
assert count(Basic(Tuple(x))) == BASIC + TUPLE
#It checks that TUPLE is counted as an operation.
assert count(Eq(x + y, S(2))) == ADD
def test_Union_as_relational():
x = Symbol('x')
assert (Interval(0, 1) + FiniteSet(2)).as_relational(x) == \
Or(And(Le(0, x), Le(x, 1)), Eq(x, 2))
assert (Interval(0, 1, True, True) + FiniteSet(1)).as_relational(x) == \
And(Lt(0, x), Le(x, 1))
def test_distribute():
A, B, C = map(Boolean, symbols('A,B,C'))
assert distribute_and_over_or(Or(And(A, B), C)) == And(Or(A, C), Or(B, C))
def test_Or():
A, B, C = map(Boolean, symbols('A,B,C'))
assert Or() == False
assert Or(A) == A
assert Or(True) == True
assert Or(False) == False
assert Or(True, True) == True
assert Or(True, False) == True
assert Or(False, False) == False
assert Or(True, A) == True
assert Or(False, A) == A
assert Or(True, False, False) == True
assert Or(True, False, A) == True
assert Or(False, False, A) == A
def simplify_guard(guards):
"""Make a big OR among guards and simplify them."""
final = Or()
for g in guards:
final = Or(final, g)
return simplify(final)
def test_eliminate_implications():
A, B, C = map(Boolean, symbols('A,B,C'))
assert eliminate_implications(Implies(A, B, evaluate=False)) == (~A) | B
assert eliminate_implications(A >> (C >> Not(B))) == Or(
Or(Not(B), Not(C)), Not(A))
def gen_state(self):
self.out("cdef dict vnum = %r" %
{n: i
for i, n in enumerate(self.variables)})
self.out()
with self.out("cdef class state :"):
for i in range(self.word):
self.out("cdef unsigned char W%s" % i)
with self.out("def __init__ (self, on=[]) :"):
self.out("cdef str v")
self.out("cdef unsigned int n")
self.out("cdef list init")
with self.out("if not on :"):
self.out("init = []")
with self.out("elif isinstance(on, str) :"):
self.out("init = on.split('|')")
with self.out("else :"):
self.out("init = list(on)")
with self.out("for v in init :"):
self.out("n = vnum[v]")
for i, n in enumerate(self.variables):
if i == 0:
self.out("if n == %s : self.%s" %
(i, self.set_1(n)))
else:
self.out("elif n == %s : self.%s" %
(i, self.set_1(n)))
with self.out("def __getitem__ (self, key) :"):
self.out("cdef unsigned int n = vnum[key]")
for i, n in enumerate(self.variables):
if i == 0:
self.out("if n == %s : return bool(self.%s)" %
(i, self.is_set(n)))
else:
self.out("elif n == %s : return bool(self.%s)" %
(i, self.is_set(n)))
with self.out("def __setitem__ (self, key, val) :"):
self.out("cdef unsigned int n = vnum[key]")
for i, n in enumerate(self.variables):
if i == 0:
self.out("if n == %s :" % i)
else:
self.out("elif n == %s :" % i)
with self.out:
self.out("if val : self.%s" % self.set_1(n))
self.out("else : self.%s" % self.set_0(n))
with self.out("def __iter__ (self) :"):
for n in self.variables:
self.out("if self.%s : yield %r" % (self.is_set(n), n))
with self.out("def __str__ (state self) :"):
self.out("cdef list l = []")
for n in self.variables:
self.out("if self.%s : l.append(%r)" % (self.is_set(n), n))
self.out("return '|'.join(l)")
with self.out("def __repr__ (state self) :"):
self.out("cdef list l = []")
for n in self.variables:
self.out("if self.%s : l.append(%r)" %
(self.is_set(n), repr(n)))
self.out("return 'state([%s])' % ', '.join(l)")
with self.out("def __eq__ (state self, state other) :"):
self.out("try: return " +
" and ".join("(self.W%s == other.W%s)" % (i, i)
for i in range(self.word)))
self.out("except : return False")
with self.out("def __ne__ (state self, state other) :"):
self.out("try : return " +
" or ".join("(self.W%s != other.W%s)" % (i, i)
for i in range(self.word)))
self.out("except : return False")
with self.out("def __hash__ (state self) :"):
self.out("return " + " + ".join("(self.W%s << %s)" %
(i,
(i % WIDTH) * 8 + i // WIDTH)
for i in range(self.word)))
with self.out("def __invert__ (self) : "):
self.out("cdef state s = state.__new__(state)")
for i in range(self.word - 1):
self.out("s.W%s = ~self.W%s" % (i, i))
last = (len(self.variables) % 8) or 0
mask = "0" * last + "1" * (8 - last)
self.out("s.W%s = 0b%s & ~self.W%s" %
(self.word - 1, mask, self.word - 1))
self.out("return s")
with self.out("def __or__ (state self, object other) :"):
self.out("cdef state s = state.__new__(state)")
self.out("cdef unsigned int n")
with self.out("if isinstance(other, str) :"):
self.out("n = vnum[other]")
for i in range(self.word):
self.out("s.W%s = self.W%s" % (i, i))
for i, n in enumerate(self.variables):
if i == 0:
self.out("if n == %s : s.%s" % (i, self.set_1(n)))
else:
self.out("elif n == %s : s.%s" %
(i, self.set_1(n)))
with self.out("elif isinstance(other, state) :"):
for i in range(self.word):
self.out("s.W%s = self.W%s | <state>other.W%s" %
(i, i, i))
with self.out("else :"):
self.out("raise TypeError(\"expected 'str' or 'state'"
" but had '%s'\" % other.__class__.__name__)")
self.out("return s")
with self.out("def __and__ (state self, object other) :"):
self.out("cdef state s")
self.out("cdef unsigned int n")
with self.out("if isinstance(other, str) :"):
self.out("s = state.__new__(state)")
self.out("n = vnum[other]")
for i, n in enumerate(self.variables):
if i == 0:
with self.out("if n == %s :" % i):
self.out("if self.%s : s.%s" %
(self.is_set(n), self.set_1(n)))
else:
with self.out("elif n == %s :" % i):
self.out("if self.%s : s.%s" %
(self.is_set(n), self.set_1(n)))
with self.out("elif isinstance(other, state) :"):
self.out("s = state.__new__(state)")
for i in range(self.word):
self.out("s.W%s = self.W%s & <state>other.W%s" %
(i, i, i))
with self.out("else :"):
self.out("raise TypeError(\"expected 'str' or 'state'"
" but had '%s'\" % other.__class__.__name__)")
self.out("return s")
with self.out("def __contains__ (self, str var) :"):
self.out("cdef unsigned int n = vnum[var]")
for i, n in enumerate(self.variables):
if i == 0:
self.out("if n == %s : return self.%s" %
(i, self.is_set(n)))
else:
self.out("elif n == %s : return self.%s" %
(i, self.is_set(n)))
for rule in chain(self.spec.constraints, self.spec.rules):
self.gen_succ(rule)
with self.out("cpdef bint transient (state self) :"):
if self.spec.constraints:
cond = Or(*(self.gen_cond(c)
for c in self.spec.constraints))
self.out("return %s" % pycode(cond))
else:
self.out("return False")
with self.out("cdef void _succ (state self, set acc) :"):
if self.spec.constraints:
self.out("cdef bint transient = 0")
self.out("cdef state s")
for rule in self.spec.constraints:
self.out("if self.%s(acc) : transient = 1" % rule.name())
if self.spec.constraints:
self.out("if transient : return")
for rule in self.spec.rules:
self.out("self.%s(acc)" % rule.name())
with self.out("cpdef set succ (state self, bint compact=False) :"):
self.out("cdef set succ, todo, done, skip")
self.out("cdef state s, q")
self.out("cdef str r, c")
self.out("todo = set()")
self.out("self._succ(todo)")
with self.out("if compact :"):
self.out("done = set()")
self.out("skip = set()")
with self.out("while todo :"):
self.out("r, s = todo.pop()")
with self.out("if s.transient() :"):
self.out("skip.add((r, s))")
self.out("succ = set() ")
self.out("s._succ(succ)")
self.out("succ.difference_update(skip)")
self.out("succ.difference_update(done)")
with self.out("for c, q in succ :"):
self.out("todo.add((r, q))")
with self.out("else :"):
self.out("done.add((r, s))")
self.out("return done")
with self.out("else :"):
self.out("return todo")
self.out("@classmethod")
with self.out("def init (cls) :"):
self.out("cdef state s = cls.__new__(cls)")
init = bitarray("0" * self.width)
for s in sorted(self.spec.meta):
if s.state.sign:
pos, val = self.vmap[s.state.name]
self.out("# %s = W%s & %s" %
(s.state.name, pos, bin8(2**val)))
init |= self.const[s.state.name]
for i, v in enumerate(reversed(init.tobytes())):
self.out("s.W%s = %s" % (i, bin8(v)))
self.out("return s")
self.out("@classmethod")
with self.out("def none (cls) :"):
self.out("return state.__new__(state)")
self.out("@classmethod")
with self.out("def all (cls) :"):
self.out("cdef state s = cls.__new__(cls)")
for i in range(self.word - 1):
self.out("s.W%s = 0b11111111" % i)
last = (len(self.variables) % 8) or 8
mask = "0" * (8 - last) + "1" * last
self.out("s.W%s = 0b%s" % (self.word - 1, mask))
self.out("return s")
self.out("@classmethod")
with self.out("def vars (cls) :"):
self.out("return %r" % (self.variables, ))
self.out()
def test_issue_8373():
x = Symbol('x', real=True)
assert simplify(Or(x < 1, x >= 1)) == S.true
def simplify_guard(guards):
"""Make a big OR among guards and simplify them."""
return simplify(Or(*guards))
def test_reduce_inequalities_multivariate():
assert reduce_inequalities([Ge(x**2, 1), Ge(y**2, 1)]) == \
And(And(Or(Le(re(x), -1), Le(1, re(x))), Eq(im(x), 0)),
And(Or(Le(re(y), -1), Le(1, re(y))), Eq(im(y), 0)))
def has_compound_trivial_condition(condition_list):
compound_condition = false
for c in condition_list:
compound_condition = Or(compound_condition, c)
return is_trivial_condition(simplify_logic(compound_condition))
def as_boolean(self):
return Or(*[And(*[Eq(sym, val) for sym, val in item]) for item in self])
def test_issue_2983():
assert Max(x, 1) * Max(x, 2) == Max(x, 1) * Max(x, 2)
assert Or(x, z) * Or(x, z) == Or(x, z) * Or(x, z)
def test_Finite_as_relational():
x = Symbol('x')
y = Symbol('y')
assert FiniteSet(1, 2).as_relational(x) == Or(Eq(x, 1), Eq(x, 2))
assert FiniteSet(y, -5).as_relational(x) == Or(Eq(x, y), Eq(x, -5))
def test_reduce_poly_inequalities_real_relational():
with assuming(Q.real(x), Q.real(y)):
assert reduce_rational_inequalities([[Eq(x**2, 0)]],
x,
relational=True) == Eq(x, 0)
assert reduce_rational_inequalities([[Le(x**2, 0)]],
x,
relational=True) == Eq(x, 0)
assert reduce_rational_inequalities(
[[Lt(x**2, 0)]], x, relational=True) is False
assert reduce_rational_inequalities(
[[Ge(x**2, 0)]], x, relational=True) is True
assert reduce_rational_inequalities([[Gt(x**2, 0)]],
x,
relational=True) == Or(
Lt(x, 0), Gt(x, 0))
assert reduce_rational_inequalities([[Ne(x**2, 0)]],
x,
relational=True) == Or(
Lt(x, 0), Gt(x, 0))
assert reduce_rational_inequalities([[Eq(x**2, 1)]],
x,
relational=True) == Or(
Eq(x, -1), Eq(x, 1))
assert reduce_rational_inequalities([[Le(x**2, 1)]],
x,
relational=True) == And(
Le(-1, x), Le(x, 1))
assert reduce_rational_inequalities([[Lt(x**2, 1)]],
x,
relational=True) == And(
Lt(-1, x), Lt(x, 1))
assert reduce_rational_inequalities([[Ge(x**2, 1)]],
x,
relational=True) == Or(
Le(x, -1), Ge(x, 1))
assert reduce_rational_inequalities([[Gt(x**2, 1)]],
x,
relational=True) == Or(
Lt(x, -1), Gt(x, 1))
assert reduce_rational_inequalities([[Ne(x**2, 1)]],
x,
relational=True) == Or(
Lt(x, -1),
And(Lt(-1, x), Lt(x, 1)),
Gt(x, 1))
assert reduce_rational_inequalities([[Le(x**2, 1.0)]],
x,
relational=True) == And(
Le(-1.0, x), Le(x, 1.0))
assert reduce_rational_inequalities([[Lt(x**2, 1.0)]],
x,
relational=True) == And(
Lt(-1.0, x), Lt(x, 1.0))
assert reduce_rational_inequalities([[Ge(x**2, 1.0)]],
x,
relational=True) == Or(
Le(x, -1.0), Ge(x, 1.0))
assert reduce_rational_inequalities([[Gt(x**2, 1.0)]],
x,
relational=True) == Or(
Lt(x, -1.0), Gt(x, 1.0))
assert reduce_rational_inequalities([[Ne(x**2, 1.0)]], x, relational=True) == \
Or(Lt(x, -1.0), And(Lt(-1.0, x), Lt(x, 1.0)), Gt(x, 1.0))
def test_piecewise_integrate():
x, y = symbols('x y', real=True, finite=True)
# XXX Use '<=' here! '>=' is not yet implemented ..
f = Piecewise(((x - 2)**2, 0 <= x), (1, True))
assert integrate(f, (x, -2, 2)) == Rational(14, 3)
g = Piecewise(((x - 5)**5, 4 <= x), (f, True))
assert integrate(g, (x, -2, 2)) == Rational(14, 3)
assert integrate(g, (x, -2, 5)) == Rational(43, 6)
g = Piecewise(((x - 5)**5, 4 <= x), (f, x < 4))
assert integrate(g, (x, -2, 2)) == Rational(14, 3)
assert integrate(g, (x, -2, 5)) == Rational(43, 6)
g = Piecewise(((x - 5)**5, 2 <= x), (f, x < 2))
assert integrate(g, (x, -2, 2)) == Rational(14, 3)
assert integrate(g, (x, -2, 5)) == -Rational(701, 6)
g = Piecewise(((x - 5)**5, 2 <= x), (f, True))
assert integrate(g, (x, -2, 2)) == Rational(14, 3)
assert integrate(g, (x, -2, 5)) == -Rational(701, 6)
g = Piecewise(((x - 5)**5, 2 <= x), (2 * f, True))
assert integrate(g, (x, -2, 2)) == 2 * Rational(14, 3)
assert integrate(g, (x, -2, 5)) == -Rational(673, 6)
g = Piecewise((1, x > 0), (0, Eq(x, 0)), (-1, x < 0))
assert integrate(g, (x, -1, 1)) == 0
g = Piecewise((1, x - y < 0), (0, True))
assert integrate(g, (y, -oo, 0)) == -Min(0, x)
assert integrate(g, (y, 0, oo)) == oo - Max(0, x)
assert integrate(g, (y, -oo, oo)) == oo - x
g = Piecewise((0, x < 0), (x, x <= 1), (1, True))
assert integrate(g, (x, -5, 1)) == Rational(1, 2)
assert integrate(g, (x, -5, y)).subs(y, 1) == Rational(1, 2)
assert integrate(g, (x, y, 1)).subs(y, -5) == Rational(1, 2)
assert integrate(g, (x, 1, -5)) == -Rational(1, 2)
assert integrate(g, (x, 1, y)).subs(y, -5) == -Rational(1, 2)
assert integrate(g, (x, y, -5)).subs(y, 1) == -Rational(1, 2)
assert integrate(g, (x, -5, y)) == Piecewise(
(0, y < 0), (y**2 / 2, y <= 1), (y - 0.5, True))
assert integrate(g, (x, y, 1)) == Piecewise(
(0.5, y < 0), (0.5 - y**2 / 2, y <= 1), (1 - y, True))
g = Piecewise((1 - x, Interval(0, 1).contains(x)),
(1 + x, Interval(-1, 0).contains(x)), (0, True))
assert integrate(g, (x, -5, 1)) == 1
assert integrate(g, (x, -5, y)).subs(y, 1) == 1
assert integrate(g, (x, y, 1)).subs(y, -5) == 1
assert integrate(g, (x, 1, -5)) == -1
assert integrate(g, (x, 1, y)).subs(y, -5) == -1
assert integrate(g, (x, y, -5)).subs(y, 1) == -1
assert integrate(g, (x, -5, y)) == Piecewise(
(-y**2 / 2 + y + 0.5, Interval(0, 1).contains(y)),
(y**2 / 2 + y + 0.5, Interval(-1, 0).contains(y)), (0, y <= -1),
(1, True))
assert integrate(g, (x, y, 1)) == Piecewise(
(y**2 / 2 - y + 0.5, Interval(0, 1).contains(y)),
(-y**2 / 2 - y + 0.5, Interval(-1, 0).contains(y)), (1, y <= -1),
(0, True))
g = Piecewise((0, Or(x <= -1, x >= 1)), (1 - x, x > 0), (1 + x, True))
assert integrate(g, (x, -5, 1)) == 1
assert integrate(g, (x, -5, y)).subs(y, 1) == 1
assert integrate(g, (x, y, 1)).subs(y, -5) == 1
assert integrate(g, (x, 1, -5)) == -1
assert integrate(g, (x, 1, y)).subs(y, -5) == -1
assert integrate(g, (x, y, -5)).subs(y, 1) == -1
assert integrate(g, (x, -5, y)) == Piecewise((0, y <= -1), (1, y >= 1),
(-y**2 / 2 + y + 0.5, y > 0),
(y**2 / 2 + y + 0.5, True))
assert integrate(g, (x, y, 1)) == Piecewise((1, y <= -1), (0, y >= 1),
(y**2 / 2 - y + 0.5, y > 0),
(-y**2 / 2 - y + 0.5, True))
def delta(self, l, X):
v = False
for i in self.formulas:
v = Or(v, i.delta(l, X))
return v
def test_piecewise_fold_piecewise_in_cond_2():
p1 = Piecewise((cos(x), x < 0), (0, True))
p2 = Piecewise((0, Eq(p1, 0)), (1 / p1, True))
p3 = Piecewise((0, Or(And(Eq(cos(x), 0), x < 0), Not(x < 0))),
(1 / cos(x), True))
assert (piecewise_fold(p2) == p3)
def delta(self, l, X):
first, second = self.formulas[0:2]
return Or(Not(first.delta(l, X)), second.delta(l, X))
def test_piecewise():
# Test canonicalization
assert Piecewise((x, x < 1), (0, True)) == Piecewise((x, x < 1), (0, True))
assert Piecewise((x, x < 1), (0, True), (1, True)) == \
Piecewise((x, x < 1), (0, True))
assert Piecewise((x, x < 1), (0, False), (-1, 1 > 2)) == \
Piecewise((x, x < 1))
assert Piecewise((x, x < 1), (0, x < 1), (0, True)) == \
Piecewise((x, x < 1), (0, True))
assert Piecewise((x, x < 1), (0, x < 2), (0, True)) == \
Piecewise((x, x < 1), (0, True))
assert Piecewise((x, x < 1), (x, x < 2), (0, True)) == \
Piecewise((x, Or(x < 1, x < 2)), (0, True))
assert Piecewise((x, x < 1), (x, x < 2), (x, True)) == x
assert Piecewise((x, True)) == x
# False condition is never retained
assert Piecewise((x, False)) == Piecewise(
(x, False), evaluate=False) == Piecewise()
raises(TypeError, lambda: Piecewise(x))
assert Piecewise((x, 1)) == x # 1 and 0 are accepted as True/False
raises(TypeError, lambda: Piecewise((x, 2)))
raises(TypeError, lambda: Piecewise((x, x**2)))
raises(TypeError, lambda: Piecewise(([1], True)))
assert Piecewise(((1, 2), True)) == Tuple(1, 2)
cond = (Piecewise((1, x < 0), (2, True)) < y)
assert Piecewise((1, cond)) == Piecewise((1, ITE(x < 0, y > 1, y > 2)))
assert Piecewise((1, x > 0), (2, And(x <= 0, x > -1))) == Piecewise(
(1, x > 0), (2, x > -1))
# Test subs
p = Piecewise((-1, x < -1), (x**2, x < 0), (log(x), x >= 0))
p_x2 = Piecewise((-1, x**2 < -1), (x**4, x**2 < 0), (log(x**2), x**2 >= 0))
assert p.subs(x, x**2) == p_x2
assert p.subs(x, -5) == -1
assert p.subs(x, -1) == 1
assert p.subs(x, 1) == log(1)
# More subs tests
p2 = Piecewise((1, x < pi), (-1, x < 2 * pi), (0, x > 2 * pi))
p3 = Piecewise((1, Eq(x, 0)), (1 / x, True))
p4 = Piecewise((1, Eq(x, 0)), (2, 1 / x > 2))
assert p2.subs(x, 2) == 1
assert p2.subs(x, 4) == -1
assert p2.subs(x, 10) == 0
assert p3.subs(x, 0.0) == 1
assert p4.subs(x, 0.0) == 1
f, g, h = symbols('f,g,h', cls=Function)
pf = Piecewise((f(x), x < -1), (f(x) + h(x) + 2, x <= 1))
pg = Piecewise((g(x), x < -1), (g(x) + h(x) + 2, x <= 1))
assert pg.subs(g, f) == pf
assert Piecewise((1, Eq(x, 0)), (0, True)).subs(x, 0) == 1
assert Piecewise((1, Eq(x, 0)), (0, True)).subs(x, 1) == 0
assert Piecewise((1, Eq(x, y)), (0, True)).subs(x, y) == 1
assert Piecewise((1, Eq(x, z)), (0, True)).subs(x, z) == 1
assert Piecewise((1, Eq(exp(x), cos(z))), (0, True)).subs(x, z) == \
Piecewise((1, Eq(exp(z), cos(z))), (0, True))
p5 = Piecewise((0, Eq(cos(x) + y, 0)), (1, True))
assert p5.subs(y, 0) == Piecewise((0, Eq(cos(x), 0)), (1, True))
assert Piecewise((-1, y < 1), (0, x < 0), (1, Eq(x, 0)),
(2, True)).subs(x, 1) == Piecewise((-1, y < 1), (2, True))
assert Piecewise((1, Eq(x**2, -1)), (2, x < 0)).subs(x, I) == 1
# Test evalf
assert p.evalf() == p
assert p.evalf(subs={x: -2}) == -1
assert p.evalf(subs={x: -1}) == 1
assert p.evalf(subs={x: 1}) == log(1)
# Test doit
f_int = Piecewise((Integral(x, (x, 0, 1)), x < 1))
assert f_int.doit() == Piecewise((1 / 2, x < 1))
# Test differentiation
f = x
fp = x * p
dp = Piecewise((0, x < -1), (2 * x, x < 0), (1 / x, x >= 0))
fp_dx = x * dp + p
assert diff(p, x) == dp
assert diff(f * p, x) == fp_dx
# Test simple arithmetic
assert x * p == fp
assert x * p + p == p + x * p
assert p + f == f + p
assert p + dp == dp + p
assert p - dp == -(dp - p)
# Test power
dp2 = Piecewise((0, x < -1), (4 * x**2, x < 0), (1 / x**2, x >= 0))
assert dp**2 == dp2
# Test _eval_interval
f1 = x * y + 2
f2 = x * y**2 + 3
peval = Piecewise((f1, x < 0), (f2, x > 0))
peval_interval = f1.subs(x, 0) - f1.subs(x, -1) + f2.subs(x, 1) - f2.subs(
x, 0)
assert peval._eval_interval(x, 0, 0) == 0
assert peval._eval_interval(x, -1, 1) == peval_interval
peval2 = Piecewise((f1, x < 0), (f2, True))
assert peval2._eval_interval(x, 0, 0) == 0
assert peval2._eval_interval(x, 1, -1) == -peval_interval
assert peval2._eval_interval(x, -1, -2) == f1.subs(x, -2) - f1.subs(x, -1)
assert peval2._eval_interval(x, -1, 1) == peval_interval
assert peval2._eval_interval(x, None, 0) == peval2.subs(x, 0)
assert peval2._eval_interval(x, -1, None) == -peval2.subs(x, -1)
# Test integration
assert p.integrate() == Piecewise((-x, x < -1), (x**3 / 3 + 4 / 3, x < 0),
(x * log(x) - x + 4 / 3, True))
p = Piecewise((x, x < 1), (x**2, -1 <= x), (x, 3 < x))
assert integrate(p, (x, -2, 2)) == 5 / 6.0
assert integrate(p, (x, 2, -2)) == -5 / 6.0
p = Piecewise((0, x < 0), (1, x < 1), (0, x < 2), (1, x < 3), (0, True))
assert integrate(p, (x, -oo, oo)) == 2
p = Piecewise((x, x < -10), (x**2, x <= -1), (x, 1 < x))
assert integrate(p, (x, -2, 2)) == Undefined
# Test commutativity
assert isinstance(p, Piecewise) and p.is_commutative is True
def delta(self, l, X):
f, g = self.formulas[0:2]
f, g = f.delta(l, X), g.delta(l, X)
return Or(And(f, g), And(Not(f), Not(g)))
def test_issue_10122():
assert solve(abs(x) + abs(x - 1) - 1 > 0, x) == Or(And(-oo < x, x < 0),
And(S.One < x, x < oo))
def test_dice():
# TODO: Make iid method!
X, Y, Z = Die('X', 6), Die('Y', 6), Die('Z', 6)
a, b, t, p = symbols('a b t p')
assert E(X) == 3 + S.Half
assert variance(X) == Rational(35, 12)
assert E(X + Y) == 7
assert E(X + X) == 7
assert E(a * X + b) == a * E(X) + b
assert variance(X + Y) == variance(X) + variance(Y) == cmoment(X + Y, 2)
assert variance(X + X) == 4 * variance(X) == cmoment(X + X, 2)
assert cmoment(X, 0) == 1
assert cmoment(4 * X, 3) == 64 * cmoment(X, 3)
assert covariance(X, Y) is S.Zero
assert covariance(X, X + Y) == variance(X)
assert density(Eq(cos(X * S.Pi), 1))[True] == S.Half
assert correlation(X, Y) == 0
assert correlation(X, Y) == correlation(Y, X)
assert smoment(X + Y, 3) == skewness(X + Y)
assert smoment(X + Y, 4) == kurtosis(X + Y)
assert smoment(X, 0) == 1
assert P(X > 3) == S.Half
assert P(2 * X > 6) == S.Half
assert P(X > Y) == Rational(5, 12)
assert P(Eq(X, Y)) == P(Eq(X, 1))
assert E(X, X > 3) == 5 == moment(X, 1, 0, X > 3)
assert E(X, Y > 3) == E(X) == moment(X, 1, 0, Y > 3)
assert E(X + Y, Eq(X, Y)) == E(2 * X)
assert moment(X, 0) == 1
assert moment(5 * X, 2) == 25 * moment(X, 2)
assert quantile(X)(p) == Piecewise((nan, (p > 1) | (p < 0)),\
(S.One, p <= Rational(1, 6)), (S(2), p <= Rational(1, 3)), (S(3), p <= S.Half),\
(S(4), p <= Rational(2, 3)), (S(5), p <= Rational(5, 6)), (S(6), p <= 1))
assert P(X > 3, X > 3) is S.One
assert P(X > Y, Eq(Y, 6)) is S.Zero
assert P(Eq(X + Y, 12)) == Rational(1, 36)
assert P(Eq(X + Y, 12), Eq(X, 6)) == Rational(1, 6)
assert density(X + Y) == density(Y + Z) != density(X + X)
d = density(2 * X + Y**Z)
assert d[S(22)] == Rational(1, 108) and d[S(4100)] == Rational(
1, 216) and S(3130) not in d
assert pspace(X).domain.as_boolean() == Or(
*[Eq(X.symbol, i) for i in [1, 2, 3, 4, 5, 6]])
assert where(X > 3).set == FiniteSet(4, 5, 6)
assert characteristic_function(X)(t) == exp(6 * I * t) / 6 + exp(
5 * I * t) / 6 + exp(4 * I * t) / 6 + exp(3 * I * t) / 6 + exp(
2 * I * t) / 6 + exp(I * t) / 6
assert moment_generating_function(X)(
t) == exp(6 * t) / 6 + exp(5 * t) / 6 + exp(4 * t) / 6 + exp(
3 * t) / 6 + exp(2 * t) / 6 + exp(t) / 6
assert median(X) == FiniteSet(3, 4)
D = Die('D', 7)
assert median(D) == FiniteSet(4)
# Bayes test for die
BayesTest(X > 3, X + Y < 5)
BayesTest(Eq(X - Y, Z), Z > Y)
BayesTest(X > 3, X > 2)
# arg test for die
raises(ValueError, lambda: Die('X', -1)) # issue 8105: negative sides.
raises(ValueError, lambda: Die('X', 0))
raises(ValueError, lambda: Die('X', 1.5)) # issue 8103: non integer sides.
# symbolic test for die
n, k = symbols('n, k', positive=True)
D = Die('D', n)
dens = density(D).dict
assert dens == Density(DieDistribution(n))
assert set(dens.subs(n, 4).doit().keys()) == set([1, 2, 3, 4])
assert set(dens.subs(n, 4).doit().values()) == set([Rational(1, 4)])
k = Dummy('k', integer=True)
assert E(D).dummy_eq(Sum(Piecewise((k / n, k <= n), (0, True)), (k, 1, n)))
assert variance(D).subs(n, 6).doit() == Rational(35, 12)
ki = Dummy('ki')
cumuf = cdf(D)(k)
assert cumuf.dummy_eq(
Sum(Piecewise((1 / n, (ki >= 1) & (ki <= n)), (0, True)), (ki, 1, k)))
assert cumuf.subs({n: 6, k: 2}).doit() == Rational(1, 3)
t = Dummy('t')
cf = characteristic_function(D)(t)
assert cf.dummy_eq(
Sum(Piecewise((exp(ki * I * t) / n, (ki >= 1) & (ki <= n)), (0, True)),
(ki, 1, n)))
assert cf.subs(
n,
3).doit() == exp(3 * I * t) / 3 + exp(2 * I * t) / 3 + exp(I * t) / 3
mgf = moment_generating_function(D)(t)
assert mgf.dummy_eq(
Sum(Piecewise((exp(ki * t) / n, (ki >= 1) & (ki <= n)), (0, True)),
(ki, 1, n)))
assert mgf.subs(n,
3).doit() == exp(3 * t) / 3 + exp(2 * t) / 3 + exp(t) / 3
def test_slow_general_univariate():
r = rootof(x**5 - x**2 + 1, 0)
assert solve(sqrt(x) + 1/root(x, 3) > 1) == \
Or(And(0 < x, x < r**6), And(r**6 < x, x < oo))
def test_piecewise_integrate4_symbolic_conditions():
a = Symbol('a', real=True, finite=True)
b = Symbol('b', real=True, finite=True)
x = Symbol('x', real=True, finite=True)
y = Symbol('y', real=True, finite=True)
p0 = Piecewise((0, Or(x < a, x > b)), (1, True))
p1 = Piecewise((0, x < a), (0, x > b), (1, True))
p2 = Piecewise((0, x > b), (0, x < a), (1, True))
p3 = Piecewise((0, x < a), (1, x < b), (0, True))
p4 = Piecewise((0, x > b), (1, x > a), (0, True))
p5 = Piecewise((1, And(a < x, x < b)), (0, True))
# check values of a=1, b=3 (and reversed) with values
# of y of 0, 1, 2, 3, 4
lim = Tuple(x, -oo, y)
for p in (p0, p1, p2, p3, p4, p5):
ans = p.integrate(lim)
for i in range(5):
reps = {a:1, b:3, y:i}
assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps))
reps = {a: 3, b:1, y:i}
assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps))
lim = Tuple(x, y, oo)
for p in (p0, p1, p2, p3, p4, p5):
ans = p.integrate(lim)
for i in range(5):
reps = {a:1, b:3, y:i}
assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps))
reps = {a:3, b:1, y:i}
assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps))
ans = Piecewise(
(0, x <= Min(a, b)),
(x - Min(a, b), x <= b),
(b - Min(a, b), True))
for i in (p0, p1, p2, p4):
assert i.integrate(x) == ans
assert p3.integrate(x) == Piecewise(
(0, x < a),
(-a + x, x <= Max(a, b)),
(-a + Max(a, b), True))
assert p5.integrate(x) == Piecewise(
(0, x <= a),
(-a + x, x <= Max(a, b)),
(-a + Max(a, b), True))
p1 = Piecewise((0, x < a), (0.5, x > b), (1, True))
p2 = Piecewise((0.5, x > b), (0, x < a), (1, True))
p3 = Piecewise((0, x < a), (1, x < b), (0.5, True))
p4 = Piecewise((0.5, x > b), (1, x > a), (0, True))
p5 = Piecewise((1, And(a < x, x < b)), (0.5, x > b), (0, True))
# check values of a=1, b=3 (and reversed) with values
# of y of 0, 1, 2, 3, 4
lim = Tuple(x, -oo, y)
for p in (p1, p2, p3, p4, p5):
ans = p.integrate(lim)
for i in range(5):
reps = {a:1, b:3, y:i}
assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps))
reps = {a: 3, b:1, y:i}
assert ans.subs(reps) == p.subs(reps).integrate(lim.subs(reps))
