integrate triggers TypeError: as_base_exp() missing 1 required positional argument: 'self

[gerritholl]

I'm new to sympy so I'm not sure how to

In [206]: (h, c, lmb, k, T) = symbols("h c λ k T")

In [207]: phi = sympy.Function('φ')

In [208]: sympy.integrate((2*h*c**2)/(lmb**5) * phi/(sympy.exp(h*c/(lmb*k*T)-1)), lmb)
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/cache.py in wrapper(*args, **kwargs)
     92                 try:
---> 93                     retval = cfunc(*args, **kwargs)
     94                 except TypeError:

/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/operations.py in __new__(cls, *args, **options)
     40 
---> 41         c_part, nc_part, order_symbols = cls.flatten(args)
     42         is_commutative = not nc_part

/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/mul.py in flatten(cls, seq)
    291                 # o = b
--> 292                 b, e = o.as_base_exp()
    293 

TypeError: as_base_exp() missing 1 required positional argument: 'self'

During handling of the above exception, another exception occurred:

TypeError                                 Traceback (most recent call last)
<ipython-input-208-23bbd328d787> in <module>()
----> 1 sympy.integrate((2*h*c**2)/(lmb**5) * phi/(sympy.exp(h*c/(lmb*k*T)-1)), lmb)

/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/decorators.py in __sympifyit_wrapper(a, b)
     75                 if not hasattr(b, '_op_priority'):
     76                     b = sympify(b, strict=True)
---> 77                 return func(a, b)
     78             except SympifyError:
     79                 return retval

/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/decorators.py in binary_op_wrapper(self, other)
    116                     else:
    117                         return f(self)
--> 118             return func(self, other)
    119         return binary_op_wrapper
    120     return priority_decorator

/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/expr.py in __mul__(self, other)
    139     @call_highest_priority('__rmul__')
    140     def __mul__(self, other):
--> 141         return Mul(self, other)
    142 
    143     @_sympifyit('other', NotImplemented)

/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/cache.py in wrapper(*args, **kwargs)
     93                     retval = cfunc(*args, **kwargs)
     94                 except TypeError:
---> 95                     retval = func(*args, **kwargs)
     96                 return retval
     97 

/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/operations.py in __new__(cls, *args, **options)
     39             return args[0]
     40 
---> 41         c_part, nc_part, order_symbols = cls.flatten(args)
     42         is_commutative = not nc_part
     43         obj = cls._from_args(c_part + nc_part, is_commutative)

/home/users/gholl/venv/stable-3.5/lib/python3.5/site-packages/sympy/core/mul.py in flatten(cls, seq)
    290                 #      e
    291                 # o = b
--> 292                 b, e = o.as_base_exp()
    293 
    294                 #  y

TypeError: as_base_exp() missing 1 required positional argument: 'self'

In [209]: print(sympy.__version__)
1.0

I'm not sure if I'm doing something wrong here, or if this is a bug in sympy.

[jksuom]

The function phi has no argument in the integrand. Should it be a constant?

[oscarbenjamin]

This issue is base on a misunderstanding. I think it can be closed now.