[Bug] Joplin CGE makes an error by not finding the correct solver path on Windows

[ywkim312]

When running the Joplin testbed notebook in the incore-docs, windows makes a following error due to not finding ipopt solver path correctly.

The error cell in notebook is

joplin_cge.run_analysis()

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
Cell In[93], line 2
      1 # Run Joplin CGE model analysis
----> 2 joplin_cge.run_analysis()

File ~\.conda\envs\pyincore\lib\site-packages\pyincore\baseanalysis.py:400, in BaseAnalysis.run_analysis(self)
    397         print("Error reading parameter: " + result[1])
    398         return result
--> 400 return self.run()

File ~\.conda\envs\pyincore\lib\site-packages\pyincore\analyses\joplincge\joplincge.py:1757, in JoplinCGEModel.run(self)
   1755 tmp = "tmp.py"
   1756 print("Calibration: ")
-> 1757 run_solver(filename, tmp)
   1759 '''
   1760 Simulation code below:
   1761 In each simulation:
   (...)
   1766 
   1767 '''
   1769 iNum = self.get_parameter("model_iterations")  # dynamic model iterations

File ~\.conda\envs\pyincore\lib\site-packages\pyincore\analyses\joplincge\joplincge.py:1672, in JoplinCGEModel.run.<locals>.run_solver(cons_filename, temp_file_name)
   1668 keepfiles = False  # True prints intermediate file names (.nl,.sol,...)
   1670 executable_path = self.get_parameter("solver_path") \
   1671     if self.get_parameter("solver_path") is not None else pyglobals.IPOPT_PATH
-> 1672 if not os.path.exists(executable_path):
   1673     print("Invalid executable path, please make sure you have Pyomo installed.")
   1675 opt = SolverFactory(solver, solver_io=solver_io, executable=executable_path)

File ~\.conda\envs\pyincore\lib\genericpath.py:19, in exists(path)
     17 """Test whether a path exists.  Returns False for broken symbolic links"""
     18 try:
---> 19     os.stat(path)
     20 except (OSError, ValueError):
     21     return False

TypeError: stat: path should be string, bytes, os.PathLike or integer, not NoneType

[navarroc]

This is not an IN-CORE issue, but a problem with ipopt not able to build solvers for windows after version 3.11.2. See conda-forge/ipopt-feedstock#55

One resolution is to download ipopt from here for windows:

https://github.com/coin-or/Ipopt/releases