integrate((x**8+1)**(-1/2),x) raises _CoeffExpValueError #26571
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I now realise that the error goes away if I change the exponent to |
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It seems to be a bug in In [12]: S(2.0).as_coeff_mul(x)
Out[12]: (1, (2.0,))
In [13]: S(2).as_coeff_mul(x)
Out[13]: (2, ()) |
diff --git a/sympy/core/numbers.py b/sympy/core/numbers.py
index b497a1bedc..2ff6011536 100644
--- a/sympy/core/numbers.py
+++ b/sympy/core/numbers.py
@@ -537,7 +537,7 @@ def __hash__(self):
def is_constant(self, *wrt, **flags):
return True
- def as_coeff_mul(self, *deps, rational=True, **kwargs):
+ def as_coeff_mul(self, *deps, rational=False, **kwargs):
# a -> c*t
if self.is_Rational or not rational:
return self, () |
diff --git a/sympy/core/mul.py b/sympy/core/mul.py
index d93dbde758..23a9ebc5fe 100644
--- a/sympy/core/mul.py
+++ b/sympy/core/mul.py
@@ -2156,8 +2156,12 @@ def _keep_coeff(coeff, factors, clear=True, sign=False):
return coeff
if coeff is S.One:
return factors
- elif coeff is S.NegativeOne and not sign:
+ elif coeff.is_Float and equal_valued(coeff, S.One):
+ return Add(*[coeff*term for term in Add.make_args(factors)])
+ elif not sign and coeff is S.NegativeOne:
return -factors
+ elif not sign and coeff.is_Float and equal_valued(coeff, S.NegativeOne):
+ return Add(*[coeff*term for term in Add.make_args(factors)])
elif factors.is_Add:
if not clear and coeff.is_Rational and coeff.q != 1:
args = [i.as_coeff_Mul() for i in factors.args]
@@ -2191,6 +2195,6 @@ def do(e):
return bottom_up(e, do)
-from .numbers import Rational
+from .numbers import Rational, equal_valued
from .power import Pow
from .add import Add, _unevaluated_Add
diff --git a/sympy/core/numbers.py b/sympy/core/numbers.py
index b497a1bedc..2ff6011536 100644
--- a/sympy/core/numbers.py
+++ b/sympy/core/numbers.py
@@ -537,7 +537,7 @@ def __hash__(self):
def is_constant(self, *wrt, **flags):
return True
- def as_coeff_mul(self, *deps, rational=True, **kwargs):
+ def as_coeff_mul(self, *deps, rational=False, **kwargs):
# a -> c*t
if self.is_Rational or not rational:
return self, ()
diff --git a/sympy/core/tests/test_expr.py b/sympy/core/tests/test_expr.py
index 8299ca312c..e52da8caf3 100644
--- a/sympy/core/tests/test_expr.py
+++ b/sympy/core/tests/test_expr.py
@@ -1250,9 +1250,10 @@ def test_as_coeff_add():
def test_as_coeff_mul():
assert S(2).as_coeff_mul() == (2, ())
- assert S(3.0).as_coeff_mul() == (1, (S(3.0),))
- assert S(-3.0).as_coeff_mul() == (-1, (S(3.0),))
+ assert S(3.0).as_coeff_mul() == (S(3.0), ())
+ assert S(-3.0).as_coeff_mul() == (S(-3.0), ())
assert S(-3.0).as_coeff_mul(rational=False) == (-S(3.0), ())
+ assert S(-3.0).as_coeff_mul(rational=True) == (-1, (S(3.0),))
assert x.as_coeff_mul() == (1, (x,))
assert (-x).as_coeff_mul() == (-1, (x,))
assert (2*x).as_coeff_mul() == (2, (x,))
diff --git a/sympy/holonomic/tests/test_holonomic.py b/sympy/holonomic/tests/test_holonomic.py
index e5069c89a8..991d2c3d85 100644
--- a/sympy/holonomic/tests/test_holonomic.py
+++ b/sympy/holonomic/tests/test_holonomic.py
@@ -624,7 +624,7 @@ def test_to_expr():
q = 1.4*a*x**2
assert p == q
p = (expr_to_holonomic(1.4*x)+expr_to_holonomic(a*x, x)).to_expr()
- q = x*(a + 1.4)
+ q = x*(1.0*a + 1.4)
assert p == q
p = (expr_to_holonomic(1.4*x)+expr_to_holonomic(x)).to_expr()
assert p == 2.4*x |
oscarbenjamin
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May 7, 2024
integrate((x**8+1)**(-1/2), x)
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With sympy version 1.12, this code:
raises a _CoeffExpValueError. The full trace is shown below. Maple gives
x*hypergeom([1/8, 1/2], [9/8], -x^8)as the value of this integral.The text was updated successfully, but these errors were encountered: