Paulo Buchsbaum

This code helps understand the power of harmony search.

Cris Luengo

Thanks for your comments.
It's was very useful for making a "best class" character array handling.

I've submitted a updated version.

I like being able to compare strings with the comparison operators! The code you wrote for comparisons is very much in the Basic style, not so much in the MATLAB style. You'll find that this function is faster:

function r = compare_strings(a,b)
% returns: 0 == equal
% 1 == a is larger
% -1 == b is larger
a = str(a); a = a.s;
b = str(b); b = b.s;
la = length(a);
lb = length(b);
l = min(la,lb);
r = a(1:l)-b(1:l);
[~,~,r] = find(r,1,'first');
if ~isempty(r)
r = sign(r);
else % they're equal, compare lengths
if la==lb
r = 0;
elseif la<lb
r = -1;
else
r = 1;
end
end
end

function r = lt(a,b)
r = compare_strings(a,b)<0;
end

(etc.)

Whenever you have two or more 'str' inputs, it is nice to convert those inputs to class 'str' explicitly. That way, it is possible to mix an object of class 'str' with a different class, for example:
a=str('hello')
a < 'goodbye'

If you do a similar conversion for the '[]' and '+' operation, you can do something like:
a=str('hello')
a = [' ',a,' ',5]

I would also overload the '*' as your 'repeat' function. Makes sense to me:
str('hello')*5

You also need to overload 'cat' and 'vertcat' methods. Rigth now, you get an error when you do [a;a]. It creates an object with 2 strings in it, which the 'disp' function cannot display.