void enumerate_program_trees(generation_table& gtable, int depth, combo::type_tree& ttree, population& pop, const reduct::rule& reduction_rule) { pop.clear(); // For each generation node with the right return-type, add it to the pop for (std::vector<generation_node>::iterator it = gtable.begin(); it != gtable.end(); ++it) { if (combo::equal_type_tree(it->node, combo::get_signature_output(ttree))) { for (node_list::iterator it2 = it->glist.begin(); it2 != it->glist.end(); it2++) pop.push_back(combo::combo_tree(*it2)); break; } } // add the right number of arguments int from_arg = combo::get_signature_inputs(ttree).size(); combo::arity_t needed_arg_count = combo::type_tree_arity(ttree); std::cout << ttree << " " << needed_arg_count << std::endl; for (int i = 1; i < depth; i++) { fill_leaves(pop, from_arg); reduce(pop, reduction_rule); increase_tree_depth(gtable, pop, i, needed_arg_count, from_arg, reduction_rule); } for (population::iterator it = pop.begin(); it != pop.end();) { bool erased = false; for (combo::combo_tree::leaf_iterator lit = it->begin_leaf(); lit != it->end_leaf(); ++lit) { if (get_arity(*lit) != 0 && !combo::is_argument(*lit)) { erased = true; break; } } if (!combo::does_contain_all_arg_up_to(*it, needed_arg_count)) { erased = true; } if (erased) it = pop.erase(it); else ++it; } }
void ihs::evolve(population &pop) const { // Let's store some useful variables. const problem::base &prob = pop.problem(); const problem::base::size_type prob_dimension = prob.get_dimension(), prob_i_dimension = prob.get_i_dimension(); const decision_vector &lb = prob.get_lb(), &ub = prob.get_ub(); const population::size_type pop_size = pop.size(); // Get out if there is nothing to do. if (pop_size == 0 || m_gen == 0) { return; } decision_vector lu_diff(prob_dimension); for (problem::base::size_type i = 0; i < prob_dimension; ++i) { lu_diff[i] = ub[i] - lb[i]; } // Int distribution to be used when picking random individuals. boost::uniform_int<population::size_type> uni_int(0,pop_size - 1); const double c = std::log(m_bw_min/m_bw_max) / m_gen; // Temporary individual used during evolution. population::individual_type tmp; tmp.cur_x.resize(prob_dimension); tmp.cur_f.resize(prob.get_f_dimension()); tmp.cur_c.resize(prob.get_c_dimension()); for (std::size_t g = 0; g < m_gen; ++g) { const double ppar_cur = m_ppar_min + ((m_ppar_max - m_ppar_min) * g) / m_gen, bw_cur = m_bw_max * std::exp(c * g); // Continuous part. for (problem::base::size_type i = 0; i < prob_dimension - prob_i_dimension; ++i) { if (m_drng() < m_phmcr) { // tmp's i-th chromosome element is the one from a randomly chosen individual. tmp.cur_x[i] = pop.get_individual(uni_int(m_urng)).cur_x[i]; // Do pitch adjustment with ppar_cur probability. if (m_drng() < ppar_cur) { // Randomly, add or subtract pitch from the current chromosome element. if (m_drng() > .5) { tmp.cur_x[i] += m_drng() * bw_cur * lu_diff[i]; } else { tmp.cur_x[i] -= m_drng() * bw_cur * lu_diff[i]; } // Handle the case in which we added or subtracted too much and ended up out // of boundaries. if (tmp.cur_x[i] > ub[i]) { tmp.cur_x[i] = boost::uniform_real<double>(lb[i],ub[i])(m_drng); } else if (tmp.cur_x[i] < lb[i]) { tmp.cur_x[i] = boost::uniform_real<double>(lb[i],ub[i])(m_drng); } } } else { // Pick randomly within the bounds. tmp.cur_x[i] = boost::uniform_real<double>(lb[i],ub[i])(m_drng); } } //Integer Part for (problem::base::size_type i = prob_dimension - prob_i_dimension; i < prob_dimension; ++i) { if (m_drng() < m_phmcr) { tmp.cur_x[i] = pop.get_individual(uni_int(m_urng)).cur_x[i]; if (m_drng() < ppar_cur) { if (m_drng() > .5) { tmp.cur_x[i] += double_to_int::convert(m_drng() * bw_cur * lu_diff[i]); } else { tmp.cur_x[i] -= double_to_int::convert(m_drng() * bw_cur * lu_diff[i]); } // Wrap over in case we went past the bounds. if (tmp.cur_x[i] > ub[i]) { tmp.cur_x[i] = lb[i] + double_to_int::convert(tmp.cur_x[i] - ub[i]) % static_cast<int>(lu_diff[i]); } else if (tmp.cur_x[i] < lb[i]) { tmp.cur_x[i] = ub[i] - double_to_int::convert(lb[i] - tmp.cur_x[i]) % static_cast<int>(lu_diff[i]); } } } else { // Pick randomly within the bounds. tmp.cur_x[i] = boost::uniform_int<int>(lb[i],ub[i])(m_urng); } } // And we push him back pop.push_back(tmp.cur_x); // We locate the worst individual. const population::size_type worst_idx = pop.get_worst_idx(); // And we get rid of him :) pop.erase(worst_idx); } }