If you have a str = '0 0 0 0 2 1' and want to remove the spaces, just use str(str~=' '). (You would be indexing into str and choosing all characters ~= space)
n = '1 2 3 4';
n_new = n(n~=' ');
Refer to Logical Indexing in the page below:https://www.mathworks.com/company/newsletters/articles/matrix-indexing-in-matlab.html
Alternatively, you can use a FORMAT specifier in your num2str call itself.
a = num2str([1 2 3 4], '%d') %this does the trick (a='1234' is the output).
However, I can see 2 possible issues with this method of mapping to a decimal integer:
1) N>10 would cause issues.
You can't work with a base more than 10. For example, if you get str = '10 11 12', concatenating to '101112' would clearly give the wrong output.
2) Strings are not ideal for this problem.
Converting integers to strings is not necessary, it would probably be inefficient to do things this way. Please refer to my answer below for another alternative.
