Give two dict() in chemstry.Reaction() not work

[Videatur]

Documentation is clear on format Reaction(react,prod). React and prod are two dicts but is you try to give a dictionary object (like a variable) you'll see an error lambda for checking type.

Example

We try to take stoichiometry:

import chempy
react,prod = chempy.balance_stoichiometry({'H2', 'O2'}, {'H2O'})
print(chempy.chemistry.Reaction(dict(react), dict(prod)))

This will give:

line 577, in check_all_integral
    if v != type(v)(int(v)):
            ^^^^^^^^^^^^^^^
TypeError: Singleton.__init__.<locals>.<lambda>() takes 1 positional argument but 2 were given

This error will not occur if you pass result (we use dict() because belance create a OrderDict) dict in clear:

chempy.chemistry.Reaction({'H2': 2, 'O2': 1}, {'H2O': 2})

Is there a way for bypass? (store dict(react) or dict(prod) in another variable will give (of course) same error.

[bjodah]

Interesting, I think SymPy's Integer class might have changed:

>>> type(react['H2'])
sympy.core.numbers.Integer

or it has always been broken, I'm not sure. Either way there's plenty of things to improve on here (PRs most welcome).

But the short term work around is to perform no checks when creating Reaction:

>>> print(chempy.chemistry.Reaction(dict(react), dict(prod), checks=()))
2 H2 + O2 -> 2 H2O

or selective disable the "all_integral" check:

>>> print(chempy.chemistry.Reaction(dict(react), dict(prod), dont_check={"all_integral"}))
2 H2 + O2 -> 2 H2O

[Videatur]

Interesting, I think SymPy's Integer class might have changed:

>>> type(react['H2'])
sympy.core.numbers.Integer

or it has always been broken, I'm not sure. Either way there's plenty of things to improve on here (PRs most welcome).

But the short term work around is to perform no checks when creating Reaction:

>>> print(chempy.chemistry.Reaction(dict(react), dict(prod), checks=()))
2 H2 + O2 -> 2 H2O

or selective disable the "all_integral" check:

>>> print(chempy.chemistry.Reaction(dict(react), dict(prod), dont_check={"all_integral"}))
2 H2 + O2 -> 2 H2O

Thank you so much, I'm gonna work on a pull to help you soon as can. I meantime this seem work fine.

[bjodah]

No stress! I reported the change in behavior in sympy/sympy#24268 too.

[montmorill]

Could we just change chempy/chemistry.py#L577 from

if v != type(v)(int(v)):

to

if v != int(v) and v != type(v)(int(v)):

It does work.

[bjodah]

Sounds promising! would you mind opening a pull request?