multifit_sqw doesn't work with parallelisation on, when using a Python function

[henrikjacobsenfys]

To reproduce, run this example, with a few modifications: https://github.com/pace-neutrons/pace-python/blob/main/examples/sqw_eval_example.py

• set m.hpc('on')
• Change the fit function on line 80 to be py_fe_sqw

The error is pasted below:

**** Waiting for parallel cluster: ClusterHerbert to start
..
**** Parallel cluster "ClusterHerbert" is ready to execute tasks
**** starting parallel task: ParallelMF_539760190
Job ParallelMF_539760190 have failed. Outputs: 
Task N1 failed. Reason: Task N1 cancelled
Task N2 failed. Error MATLAB:mex:CppMexException; Message Python function is not callable.
Warning:  Number: 2 parallel tasks out of total: 2 tasks have failed
***** Error output N 1Error using receive_all_messages_
Node 1: interrupted receive from node 2 by cancellation message: cancelled, Reason: Python function is not callable.

Error in iMessagesFramework/receive_all (line 314)

Error in JobExecutor/reduce (line 669)

Error in MFParallel_Job/setup (line 99)

Error in parallel_worker (line 274)

Error in worker_v4 (line 49)

Error in call>eval_ans (line 94)
...
Error in worker_v4 (line 49)

Error in call>eval_ans (line 94)

Error in call (line 36)
Output is truncated. View as a [scrollable element](command:cellOutput.enableScrolling?193d7a23-0bb6-403d-bf9e-8026a91ec293) or open in a [text editor](command:workbench.action.openLargeOutput?193d7a23-0bb6-403d-bf9e-8026a91ec293). Adjust cell output [settings](command:workbench.action.openSettings?%5B%22%40tag%3AnotebookOutputLayout%22%5D)...
---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
Cell In[5], [line 12](vscode-notebook-cell:?execution_count=5&line=12)
     [10](vscode-notebook-cell:?execution_count=5&line=10) # Time it to see how long it takes to do the fit
     [11](vscode-notebook-cell:?execution_count=5&line=11) m.tic()
---> [12](vscode-notebook-cell:?execution_count=5&line=12) wfit, fitdata = kk.fit('comp')
     [13](vscode-notebook-cell:?execution_count=5&line=13) t_ana = m.toc();
     [14](vscode-notebook-cell:?execution_count=5&line=14) print(t_ana)

File c:\Users\henrikjacobsen3\AppData\Local\miniforge3\envs\pace_env\lib\site-packages\libpymcr\MatlabProxyObject.py:111, in matlab_method.__call__(self, *args, **kwargs)
    [109](file:///C:/Users/henrikjacobsen3/AppData/Local/miniforge3/envs/pace_env/lib/site-packages/libpymcr/MatlabProxyObject.py:109) args += sum(kwargs.items(), ())
    [110](file:///C:/Users/henrikjacobsen3/AppData/Local/miniforge3/envs/pace_env/lib/site-packages/libpymcr/MatlabProxyObject.py:110) args = unwrap(args, ifc)
--> [111](file:///C:/Users/henrikjacobsen3/AppData/Local/miniforge3/envs/pace_env/lib/site-packages/libpymcr/MatlabProxyObject.py:111) rv = ifc.call(self.method, self.proxy.handle, *args, nargout=nargout)
    [112](file:///C:/Users/henrikjacobsen3/AppData/Local/miniforge3/envs/pace_env/lib/site-packages/libpymcr/MatlabProxyObject.py:112) return wrap(rv, ifc)

RuntimeError: MatlabExecutionError: 
  File "C:\Users\henrikjacobsen3\AppData\Local\Temp\henrikjacobsen3\mcrCache9.14\pace_21\pace_2023a\buildtmp\CTF\Horace\herbert_core\applications\multifit\@mfclass\private\multifit_lsqr_par.m", line 270, function "multifit_lsqr_par"
  File "C:\Users\henrikjacobsen3\AppData\Local\Temp\henrikjacobsen3\mcrCache9.14\pace_21\pace_2023a\buildtmp\CTF\Horace\herbert_core\applications\multifit\@mfclass\private\multifit_lsqr.m", line 200, function "multifit_lsqr"
  File "C:\Users\henrikjacobsen3\AppData\Local\Temp\henrikjacobsen3\mcrCache9.14\pace_21\pace_2023a\buildtmp\CTF\Horace\herbert_core\applications\multifit\@mfclass\fit.m", line 81, function "fit"
  File "C:\Users\henrikjacobsen3\AppData\Local\Temp\henrikjacobsen3\mcrCache9.14\pace_21\pace_2023a\buildtmp\CTF\Horace\horace_core\sqw\multifit_subclasses\mfclass_Horace_sqw.m", line 814, function "mfclass_Horace_sqw.fit"
  File "C:\Users\henrikjacobsen3\AppData\Local\Temp\henrikjacobsen3\mcrCache9.14\pace_21\pace_2023a\src\call.m", line 20, function "call"

HERBERT:multifit_lsqr_par:parallel_error: Error in MFParallel_Job, please see report