Warning: Could not find appropriate function on path loading function handle

After I updated to matlab2018a, my commercial software "SARproz" which runs under matlab failed to process data. Matlab gives this error:

Warning: Could not find appropriate function on path loading function handle C:\Program Files\MATLAB\R2018a\toolbox\images\images\private\resampsep.mexw64>resampsep > In parallel_function>make_general_channel/channel_general (line 917) In remoteParallelFunction (line 46)

I have checked that this function exists in the directory. All of my data come up with the same error when using matlab2018, but they are good with matlab2017. I think this is a compatibility problem. How can it be solved ?

Answer 1

[Jan]

This is not a question for the general Matlab forum. Contact the author of the software.

The software is from 2015 and all I find there is: "Matlab 2012 or higher". It is possible that the compiled MEX files are not running under 2018a anymore.

[Jan]

[MOVED from section for answers] Jinghui Wang wrote:

Thank you for your answer. Before I submit the question here, I have contact the author of software who replied I should write to Mathworks. At this moment I'm confused whether matlab2018 or the software should be modified to correct this error. Since this is a compatibility problem, and I can't solve it. I just switched back to Matlab2017, and now the error disappeared.

[Jan]

[MOVED from section for answers] Jinghui Wang wrote:

Hi Jan, the issue happens in tformarray. The function handle is @resampsep. The handle is defined in makeresampler. Makeresampler is called outside of a parfor loop. Then inside the parfor loop, the function handle becomes suddenly 'UNKNOWN Function'. If you replace the parfor loop with a simple for loop, the problem does not happen. This behavior appeared in the 2018a version. Till the previous version, no problems. So: why is this happening? Second: how to solve it? In any case, it looks to me a Matlab bug. Thanks and best

[Daniele Perissin]

Hi Jan,

do you consider this matter closed or does the previous comment about tformarray/makeresampler/parfor loop give a new light to the issue?

thanks

[Pietro Milillo]

Hi Jan,

I have the same issue. The same code works on Matlab2017b while it gives me the exact same error in 2018b.

Can you please advice? I think it is a bug in the new Matlab version.

Warning: Could not find appropriate function on path loading function handle /Applications/MATLAB_R2018b.app/toolbox/images/images/private/resampsep.mexmaci64>resampsep

> In parallel_function>make_general_channel/channel_general (line 923)

[Jan]

@Daniela, Pietro, Jinghui: Withoujt seeing the original code and having the commercial software, I cannot run any tests or understand, when the problem occurs. So please contact the author of the commercial software and ask the official Matlab support for help. Both will ask for code, which repdoduces the problem also.

Answer 2

[Daniele Perissin]

Hi Jan,

I do not know how this forum works, I never got the replies above, I just discovered them by chance today.

Just for the sake of closing the topic, please check the following:

https://www.mathworks.com/matlabcentral/answers/420596-function-handle-parfor-loop-matlab-2018-possible-bug?s_tid=prof_contriblnk

thanks and best

Daniele