def test_diff():
assert Rational(1, 3).diff(x) is S.Zero
assert I.diff(x) is S.Zero
assert pi.diff(x) is S.Zero
assert x.diff(x, 0) == x
assert (x**2).diff(x, 2, x) == 0
assert (x**2).diff((x, 2), x) == 0
assert (x**2).diff((x, 1), x) == 2
assert (x**2).diff((x, 1), (x, 1)) == 2
assert (x**2).diff((x, 2)) == 2
assert (x**2).diff(x, y, 0) == 2*x
assert (x**2).diff(x, (y, 0)) == 2*x
assert (x**2).diff(x, y) == 0
raises(ValueError, lambda: x.diff(1, x))
p = Rational(5)
e = a*b + b**p
assert e.diff(a) == b
assert e.diff(b) == a + 5*b**4
assert e.diff(b).diff(a) == Rational(1)
e = a*(b + c)
assert e.diff(a) == b + c
assert e.diff(b) == a
assert e.diff(b).diff(a) == Rational(1)
e = c**p
assert e.diff(c, 6) == Rational(0)
assert e.diff(c, 5) == Rational(120)
e = c**Rational(2)
assert e.diff(c) == 2*c
e = a*b*c
assert e.diff(c) == a*b
def build_ideal(x, terms):
"""
Build generators for our ideal. Terms is an iterable with elements of
the form (fn, coeff), indicating that we have a generator fn(coeff*x).
If any of the terms is trigonometric, sin(x) and cos(x) are guaranteed
to appear in terms. Similarly for hyperbolic functions. For tan(n*x),
sin(n*x) and cos(n*x) are guaranteed.
"""
I = []
y = Dummy('y')
for fn, coeff in terms:
for c, s, t, rel in ([cos, sin, tan,
cos(x)**2 + sin(x)**2 - 1], [
cosh, sinh, tanh,
cosh(x)**2 - sinh(x)**2 - 1
]):
if coeff == 1 and fn in [c, s]:
I.append(rel)
elif fn == t:
I.append(t(coeff * x) * c(coeff * x) - s(coeff * x))
elif fn in [c, s]:
cn = fn(coeff * y).expand(trig=True).subs(y, x)
I.append(fn(coeff * x) - cn)
return list(set(I))
def reduce_rational_inequalities_wrap(condition, var):
if condition.is_Relational:
return _reduce_inequalities([[condition]], var, relational=False)
if isinstance(condition, Or):
return Union(*[_reduce_inequalities([[arg]], var, relational=False)
for arg in condition.args])
if isinstance(condition, And):
intervals = [_reduce_inequalities([[arg]], var, relational=False)
for arg in condition.args]
I = intervals[0]
for i in intervals:
I = I.intersect(i)
return I
def build_ideal(x, terms):
"""
Build generators for our ideal. Terms is an iterable with elements of
the form (fn, coeff), indicating that we have a generator fn(coeff*x).
If any of the terms is trigonometric, sin(x) and cos(x) are guaranteed
to appear in terms. Similarly for hyperbolic functions. For tan(n*x),
sin(n*x) and cos(n*x) are guaranteed.
"""
I = []
y = Dummy('y')
for fn, coeff in terms:
for c, s, t, rel in (
[cos, sin, tan, cos(x)**2 + sin(x)**2 - 1],
[cosh, sinh, tanh, cosh(x)**2 - sinh(x)**2 - 1]):
if coeff == 1 and fn in [c, s]:
I.append(rel)
elif fn == t:
I.append(t(coeff*x)*c(coeff*x) - s(coeff*x))
elif fn in [c, s]:
cn = fn(coeff*y).expand(trig=True).subs(y, x)
I.append(fn(coeff*x) - cn)
return list(set(I))
def test_issue_21721():
a = Symbol('a', real=True)
I = integrate(1/(pi*(1 + (x - a)**2)), x)
assert I.limit(x, oo) == S.Half
def test_issue_5486_bug():
from sympy.core.expr import Expr
from sympy.core.numbers import I
assert abs(Expr._from_mpmath(I._to_mpmath(15), 15) - I) < 1.0e-15
