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Constant mutation + simplification added

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This commit is contained in:
maartenkeijzer 2005-10-07 11:31:01 +00:00
commit 4042798417
9 changed files with 225 additions and 46 deletions
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53
eo/contrib/mathsym/eo_interface/eoSymMutate.h
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@ -53,6 +53,8 @@ class eoSymSubtreeMutate : public eoMonOp<EoType> {
* is_rate_absolute : don't rescale the rate to the size of the tree
*/
extern bool mutate(Sym& sym, double p, const LanguageTable& table);
template <class EoType>
class eoSymNodeMutate : public eoMonOp<EoType> {
@ -60,36 +62,7 @@ class eoSymNodeMutate : public eoMonOp<EoType> {
double own_mutation_rate;
bool own_is_rate_absolute;
// these two can (should?) move to an impl file
bool mutate(Sym& sym, double p) {
std::pair<Sym, bool> r = do_mutate(sym, p);
sym = r.first;
return r.second;
}
std::pair<Sym, bool> do_mutate(Sym sym, double p) {
bool changed = false;
SymVec args = sym.args();
if (rng.flip(p)) {
token_t new_token = table.get_random_function( args.size());
if (new_token != sym.token()) changed = true;
sym = Sym(new_token, args);
}
for (unsigned i = 0; i < args.size(); ++i) {
std::pair<Sym,bool> r = do_mutate(args[i], p);
changed |= r.second;
if (r.second)
args[i] = r.first;
}
if (changed)
return std::make_pair(Sym(sym.token(), args), true);
// else
return std::make_pair(sym, false);
}
public:
double& mutation_rate;
@ -114,9 +87,29 @@ class eoSymNodeMutate : public eoMonOp<EoType> {
double p = mutation_rate;
if (!is_rate_absolute) p /= _eo.size();
return mutate(_eo, p);
return mutate(_eo, p, table);
}
};
/**
* Simple constant mutation class, adds gaussian noise (configurable variance) to the individuals
**/
extern bool mutate_constants(Sym& sym, double stdev);
template <class EoType>
class eoSymConstantMutate : public eoMonOp<EoType> {
double& stdev;
public :
eoSymConstantMutate(double& _stdev) : stdev(_stdev) {}
bool operator()(EoType& _eo) {
return mutate_constants(_eo, stdev);
}
};
#endif