NotImplementedError for CUMIPMT function.

[austinulfers]

Describe the bug
It seems that the CUMIPMT function doesn't seem to be supported.

To Reproduce
func = formulas.Parser().ast('=CUMIPMT(A1/12,360,A2,1,12,)')[1].compile()
func(0.04, 181800)

Expected behavior
It should return the value 606.

Screenshots

Traceback (most recent call last):
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\sol.py", line 631, in _evaluate_node
    value = self._evaluate_function(args, node_id, node_attr, attr,
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\sol.py", line 603, in _evaluate_function
    res = async_process(
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\asy\__init__.py", line 178, in async_process
    res = (exe and exe.process_funcs or _process_funcs)(
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\asy\__init__.py", line 136, in _process_funcs
    r['res'] = e.process(sid, fn, *args, **kw) if e else fn(*args, **kw)
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\formulas\functions\__init__.py", line 101, in not_implemented
    raise NotImplementedError
NotImplementedError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "c:/Users/austi/OneDrive/git-projects/arrived-homes/DataCalculations/Proforma/test.py", line 7, in <module>
    print(func(0.04, 181800))
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\dsp.py", line 1359, in __call__
    if not s._set_node_output(
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\sol.py", line 592, in _set_node_output
    return self._set_function_node_output(node_id, node_attr, no_call,
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\sol.py", line 814, in _set_function_node_output
    res = async_thread(self, args, node_attr, node_id, **kw)
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\asy\__init__.py", line 252, in async_thread
    return sol._evaluate_node(args, node_attr, node_id, *a, **kw)
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\sol.py", line 649, in _evaluate_node
    self._warning(msg, node_id, ex)
  File "C:\Users\austi\OneDrive\git-projects\arrived-homes\DataCalculations\Proforma\env\lib\site-packages\schedula\utils\sol.py", line 1266, in _warning
    raise DispatcherError(
schedula.utils.exc.DispatcherError: ("Failed DISPATCHING '%s' due to:\n  %r", 'CUMIPMT', NotImplementedError())

Desktop (please complete the following information):

• OS: Windows 10
• Python: 3.8.6
• Formulas: 1.1.0

[vinci1it2000]

The formula is now implemented, but the written formula is incorrect, and I cannot determine the return value you suggested. Using excel the formula =CUMIPMT(0.04/12,360,181800,1,12, 1) returns -6585.8.

>>> import formulas
>>> func = formulas.Parser().ast('=CUMIPMT(A1/12,360,A2,1,12,1)')[1].compile()
>>> func(0.04, 181800)
-6585.775266002218