46 lines
1.4 KiB
C++
46 lines
1.4 KiB
C++
/*
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* Copyright (C) 2005 Maarten Keijzer
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of version 2 of the GNU General Public License as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <utils/eoRNG.h>
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#include "TreeBuilder.h"
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Sym TreeBuilder::make_terminal() const {
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if (rng.flip(vcprob)) {
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return table.get_random_var();
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}
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return table.get_random_const();
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}
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Sym TreeBuilder::build_tree(unsigned max_depth, bool grow) const {
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if (max_depth == 0 || grow && rng.random(2) == 0) {
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return make_terminal();
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}
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// pick a random function, no matter what arity
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functor_t func = table.get_random_function();
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SymVec args(func.arity);
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for (unsigned i = 0; i < args.size(); ++i) {
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args[i] = build_tree(max_depth-1, grow);
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}
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return Sym(func.token, args);
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}
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