Data commit

Task/Evolutionary-algorithm/Octave/evolutionary-algorithm.octave

@@ -0,0 +1,52 @@
+global target;
+target = split("METHINKS IT IS LIKE A WEASEL", "");
+charset = ["A":"Z", " "];
+p = ones(length(charset), 1) ./ length(charset);
+parent = discrete_rnd(charset, p, length(target), 1);
+mutaterate = 0.1;
+
+C = 1000;
+
+function r = fitness(parent, target)
+  r = sum(parent == target) ./ length(target);
+endfunction
+
+function r = mutate(parent, mutaterate, charset)
+  r = parent;
+  p = unifrnd(0, 1, length(parent), 1);
+  nmutants = sum( p < mutaterate );
+  if (nmutants)
+    s = discrete_rnd(charset, ones(length(charset), 1) ./ length(charset),nmutants,1);
+    r( p < mutaterate ) = s;
+  endif
+endfunction
+
+function r = evolve(parent, mutatefunc, fitnessfunc, C, mutaterate, charset)
+  global target;
+  children = [];
+  for i = 1:C
+    children = [children, mutatefunc(parent, mutaterate, charset)];
+  endfor
+  children = [parent, children];
+  fitval = [];
+  for i = 1:columns(children)
+    fitval = [fitval, fitnessfunc(children(:,i), target)];
+  endfor
+  [m, im] = max(fitval);
+  r = children(:, im);
+endfunction
+
+function printgen(p, t, i)
+  printf("%3d %5.2f %s\n", i, fitness(p, t), p');
+endfunction
+
+i = 0;
+
+while( !all(parent == target) )
+  i++;
+  parent = evolve(parent, @mutate, @fitness, C, mutaterate, charset);
+  if ( mod(i, 1) == 0 )
+    printgen(parent, target, i);
+  endif
+endwhile
+disp(parent');