MATLAB: Making an executable with input arguments using codegen

Question

I'm trying to compile a Matlab code using codegen and making an executable. The thing is that after compilation, I can't seem to successfully call the app from matlab along with the relevant input. I'll explain:

To make things simple, let's assume that the purpose of my program is to create a '.txt' file named 'my_text.txt' and print an input string inside, like so:

function PrintMyString(input_str) %#codegen

      fid = fopen('my_text.txt','w');
      fprintf(fid,'My input string is: %s',input_str);
      fclose(fid);
end

Now, I tried to compile the code above using the following script:

str = 'pre_defining_the_input_variable_by_example';
codegen -config config_obj PrintMyString -args {str}

when config_obj is the code generation configuration defined somewhere earlier.

The compilation was successful, but as I mentioned before, when I tried to activate the program it didn't go as planned. I tried various options for calling, such as:

system(['PrintMyString.exe ',str]);

The text file was created, but no input string was printed (all that appeared was the line "My input string is: ").

I also tried adding a main function that calls the original PrintMyString function, like so:

function main() %#codegen
      str = 'some_string';
      PrintMyString(str);
end

I compiled it like that:

str = 'pre_defining_the_input_variable_by_example';
codegen -config config_obj main PrintMyString -args {str}

And that worked, but obviously it doesn't help because the input string has to be sent to the program from outside.

Any ideas? What am I doing wrong?

Answer 1

Hi,

it's probably not a question of the code generation but your main file: you compile to an executable, so probably your config_obj carries the information about the main file that you have to have. This main file should be able to take string input and pass it to the generated C code.

Maybe you can share your main file and we can take a look.

Titus