"argument is not an mpz" while loading dill-ed SymPy expressions.

[musically-ut]

This is probably related to #2724.

The .dill file which causes this for me is here.

I see the following error:

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-39-155386c49816> in <module>()
----> 1 read_soln(3, 4)

<ipython-input-34-a5139f00b443> in read_soln(N, M)
      2 def read_soln(N, M):
      3     with open(f_name_templ.format(N, M), 'rb') as f:
----> 4         data = dill.load(f)
      5         print('Successfully read ({},{}).'.format(N, M))
      6         return data

/home/utkarshu/miniconda3/lib/python3.5/site-packages/dill/dill.py in load(file)
    248     pik = Unpickler(file)
    249     pik._main = _main_module
--> 250     obj = pik.load()
    251     if type(obj).__module__ == _main_module.__name__: # point obj class to main
    252         try: obj.__class__ == getattr(pik._main, type(obj).__name__)

/home/utkarshu/miniconda3/lib/python3.5/pickle.py in load(self)
   1037                     raise EOFError
   1038                 assert isinstance(key, bytes_types)
-> 1039                 dispatch[key[0]](self)
   1040         except _Stop as stopinst:
   1041             return stopinst.value

/home/utkarshu/miniconda3/lib/python3.5/pickle.py in load_reduce(self)
   1392         args = stack.pop()
   1393         func = stack[-1]
-> 1394         stack[-1] = func(*args)
   1395     dispatch[REDUCE[0]] = load_reduce
   1396 

/home/utkarshu/miniconda3/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/utkarshu/miniconda3/lib/python3.5/site-packages/sympy/core/add.py in flatten(cls, seq)
    132                     return [S.NaN], [], None
    133                 if coeff.is_Number:
--> 134                     coeff += o
    135                     if coeff is S.NaN:
    136                         # we know for sure the result will be nan

/home/utkarshu/miniconda3/lib/python3.5/site-packages/sympy/core/numbers.py in __add__(self, other)
   1787         elif isinstance(other, Integer):
   1788             return Integer(self.p + other.p)
-> 1789         return Rational.__add__(self, other)
   1790 
   1791     def __radd__(self, other):

/home/utkarshu/miniconda3/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/utkarshu/miniconda3/lib/python3.5/site-packages/sympy/core/numbers.py in __add__(self, other)
   1374             return Rational(self.p*other.q + self.q*other.p, self.q*other.q)
   1375         elif isinstance(other, Float):
-> 1376             return other + self
   1377         else:
   1378             return Number.__add__(self, other)

/home/utkarshu/miniconda3/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/utkarshu/miniconda3/lib/python3.5/site-packages/sympy/core/numbers.py in __add__(self, other)
    928         if isinstance(other, Number):
    929             rhs, prec = other._as_mpf_op(self._prec)
--> 930             return Float._new(mlib.mpf_add(self._mpf_, rhs, prec, rnd), prec)
    931         return Number.__add__(self, other)
    932 

/home/utkarshu/miniconda3/lib/python3.5/site-packages/mpmath/libmp/libmpf.py in mpf_add(s, t, prec, rnd, _sub)
    766         return t
    767     if sman:
--> 768         return normalize1(ssign, sman, sexp, sbc, prec or sbc, rnd)
    769     return s
    770 

TypeError: argument is not an mpz

I am using Python 3.5.2 with dill version 0.2.5 and sympy version 1.0.

[oscarbenjamin]

Is this still a problem? Can you show how to reproduce this?

[musically-ut]

Okay, just tried this with the .dill file I had linked to and it worked with:

In [4]: sympy.__version__
Out[4]: '1.3'

In [5]: dill.__version__
Out[5]: '0.2.8.2'

Hence, I will close the issue.