<s>[INST] This is a follow-up to my previous question about mapping a list of strings to two new lists in octave. I tried setting up the following code:

```
existing_names = ["name1", "name2", "name3"];
desired_pairs = [];

numElems = length(existing_names);
for i = 1:1:numElems
  existing_name = existing_names(i);
  [tokens, matches] = strtok(existing_name, '_');
  word_count = length(strsplit(existing_name, '_'));
  if word_count > 1
    % This line is not producing the desired output
    desired_pairs = [desired_pairs; string(tokens)];
  endif
endfor
desired_pairs
```

I'm experiencing some issues with the line inside the if statement. It keeps saying "horizontal dimensions mismatch". The error occurs because the stroke function outputs three different types of variables and trying to combine them into a single list, I am forced to create a "cell" structure instead of a standard list. But even with a cell structure, I'm struggling to combine the items from each iteration.

Can someone please provide a suggested solution?[/INST]