[SOLVED] Deploy an matlab file to executable

Deploy an matlab file to executable

I want to deploy an m file into an executable. I am using mcc command: mcc -m epidemic.m. Epidemic is my function which takes no arguments and returns a vector and write that vector to txt. Mcc creates epidemic.exe and when I am running that exe it creates the txt file however it seems that it doesnt return values (the return value of .exe). I am trying to run the exe from matlab using:

cmd = ['epidemic.exe '];
system(cmd);

It return cmdout " and status 0. How can I take the returned values of the .exe?

Solution

When you compile matlab code like:

function [out1, out2] = epidemic(in1, in2, in3)
%[
    ...
%]

to standalone (mcc -m epidemeic.m), Matlab produces somehow the following pseudo c-code and compiles it to .exe:

int main(int argc, char** argv)
{
     // Load compiled code produced by mcc
     HMCRInstance* hInst = loadByteCodeProducedByMccFromResources();

     // Similar to have wrote in matlab "epidemic(argv[0], argv[1], ...)"
     // 1) Without asking for any argument output
     // 2) Argument inputs are passed as strings
     int errorCode = mclFevalFromExeArg(hInst, "epidemic", argc, argv);

     return errorCode; // only indicates if call to 'mclFEvalFromExeArg'
                       // succeded, it does not relate to out1, out2 at all.
}

NB: If you want to see the exact code produced by mcc, use mcc -W main -T codegen epidemic.m

So, directly compiling to standalone, you cannot work with outputs of your Matlab function. If you need to play around with output arguments of epidemic, either

[Simple solution] Consider saving outputs to files or display them to shell console using disp (NB: you can use isdeployed in your .m file to check if you're running from matlab or from compiled code).
[Advanced solution] Consider compiling your code to shared library (mcc -l epidemic.m) instead of standalone (mcc -m epidemeic.m)

NB: When you compile your code to shared library, mcc will produce a dll that exports the following function:

extern LIB_epidemeic_C_API 
bool MW_CALL_CONV mlxEpidemic(int nlhs, mxArray *plhs[], int nrhs, mxArray *prhs[]);

nrhs/prhs are the number of input arguments and their values (as mxArray type). And nlhs/plhs are the ouput arguments you want to have when calling epidemic. Up to you to do the marshaling between mxArray and equivalent C native type.

EDIT

As you indicate that epidemic returns a vector of values, you can display them from standalone like this:

function [output] = epidemic(v1, v2, v3)
%[
    % When called from system cmd line, v1, v2, v3 are passed
    % as string. Here is how to convert them to expected type if required
    if (ischar(v1)), v1 = str2double(v1); end
    if (ischar(v2), v2 = str2double(v2); end
    if (ischar(v3)), v3 = str2double(v3); end

    ...
    output = ...;
    ...

    if (isdeployed())
        disp(output);  
    end
%]