Removing cellfun, regexp and function handles

Hi all,

I've been trying to rewrite a line of Matlab code so that I can convert the code into C using Matlab Coder. The original line was this:

my_index = cellfun(@(x)~isempty(x),regexp({my_results.name},'my_string'));

At the moment the code I've got to do the same as the line above is:

n = numel(my_results);
my_results = false(n,1);
for ii = 1:n
  my_results(ii) = coder.ceval(strstr(my_results(ii).name,'my_string'));
end
len_new_my_results = length(new_my_results);
for ii = len_new_my_results:-1:1
   my_index(ii) = ~isempty(new_my_results{ii});
end

This however is giving me an error saying "Improper index matrix referencing" at the line my_results(ii) = coder.ceval(strstr(my_results(ii).name,'my_string'));

I have tried reading up about what it means and I think it has something to do with a variable being an input to a function (this is true in my case, my_results is an input to the function where this piece of code is)? Is there a way to get around it?

Any pointers in the right direction will be greatly appreciated. Thank you.

[Randy Souza]

I have restored the original text of this question.

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Answer 1

[Sean de Wolski]

Don't convert to cell:

 new_my_results = regexp({my_results.name},'my_string');

Instead use (I assume this is a struct array):

n = numel(my_results);
my_results = false(n,1);
for ii = 1:n
  my_results(ii) = mystrfind(my_results(ii).name,'my_string');
end

You'll have to write your own mystrfind since none of the string finding things appear to be supported for codegen. This could be doen real easily with a for-loop over the values. You could also consider using coder.ceval to just use the C string finding function.

[Jess]

Thank you!