add FastGA foundry and eoStandardBitMutation variants
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11 changed files with 598 additions and 4 deletions
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@ -162,6 +162,7 @@
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#include "eoForge.h"
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#include "eoAlgoFoundry.h"
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#include "eoAlgoFoundryEA.h"
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#include "eoAlgoFoundryFastGA.h"
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#include "eoEvalFoundryEA.h"
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//-----------------------------------------------------------------------------
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@ -32,7 +32,7 @@
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* and hold the link to the encoding. @see eoAlgoFoundryEA
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*
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* As with eoForgeVector, adding a managed operator
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*is done through public member variable's `add` method,
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* is done through public member variable's `add` method,
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* which takes the class name as template and its constructor's parameters
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* as arguments. For example:
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* @code
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@ -74,7 +74,7 @@ class eoOperatorFoundry : public eoForgeVector< Itf >
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* @endcode
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*
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* In a second step, the operators to be used should be selected
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* by indicating their index, just like if the foundry was a array:
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* by indicating their index, just like if the foundry was an array:
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* @code
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* foundry = {0, 1, 2};
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* // ^ ^ ^
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251
eo/src/eoAlgoFoundryFastGA.h
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251
eo/src/eoAlgoFoundryFastGA.h
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@ -0,0 +1,251 @@
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/*
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation;
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version 2 of the License.
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This library 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 GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library; 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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© 2020 Thales group
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Authors:
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Johann Dreo <johann.dreo@thalesgroup.com>
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*/
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#ifndef _eoAlgoFoundryFastGA_H_
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#define _eoAlgoFoundryFastGA_H_
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#include <array>
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#include <tuple>
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#include <limits>
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/** A class that assemble an eoEasyEA on the fly, given a combination of available operators.
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*
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* The foundry should first be set up with sets of operators
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* for the main modules of an EA:
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* continuators, crossovers, mutations, selection and replacement operators.
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*
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* This is done through public member variable's `add` method,
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* which takes the class name as template and its constructor's parameters
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* as arguments. For example:
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* @code
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* foundry.selectors.add< eoStochTournamentSelect<EOT> >( 0.5 );
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* @endcode
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*
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* @warning If the constructor takes a reference YOU SHOULD ABSOLUTELY wrap it
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* in a `std::ref`, or it will silently be passed as a copy,
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* which would effectively disable any link between operators.
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*
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* In a second step, the operators to be used should be selected
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* by indicating their index, passing an array of eight elements:
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* @code
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* foundry.select({0, 1, 2, 3, 4, 5, 6, 7});
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* @endcode
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*
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* @note: by default, the firsts of the eight operators are selected.
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*
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* If you don't (want to) recall the order of the operators in the encoding,
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* you can use the `index()` member, for example:
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* @code
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* foundry.at(foundry.continuators.index()) = 2; // select the third continuator
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* @endcode
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*
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* Now, you can call the fourdry just like any eoAlgo, by passing it an eoPop:
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* @code
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* foundry(pop);
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* @encode
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* It will instantiate the needed operators (only) and the algorithm itself on-the-fly,
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* and then run it.
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*
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* @note: Thanks to the underlying eoOperatorFoundry, not all the added operators are instantiated.
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* Every instantiation is deferred upon actual use. That way, you can still reconfigure them
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* at any time with `eoForgeOperator::setup`, for example:
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* @code
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* foundry.selector.at(0).setup(0.5); // using constructor's arguments
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* @endcode
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*
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* @ingroup Foundry
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* @ingroup Algorithms
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*/
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template<class EOT>
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class eoAlgoFoundryFastGA : public eoAlgoFoundry<EOT>
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{
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public:
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/** The constructon only take an eval, because all other operators
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* are stored in the public containers.
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*/
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eoAlgoFoundryFastGA( eoInit<EOT> & init, eoEvalFunc<EOT>& eval, size_t max_evals = 10000, size_t max_restarts = std::numeric_limits<size_t>::max() ) :
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eoAlgoFoundry<EOT>(8),
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continuators(0, true), // Always re-instantiate continuators, because they hold a state.
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crossover_rates(1, false),
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crossovers(2, false),
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mutation_rates(3, false),
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mutations(4, false),
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selectors(5, false),
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pop_sizes(6, false),
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replacements(7, false),
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_eval(eval),
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_init(init),
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_max_evals(max_evals),
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_max_restarts(max_restarts)
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{ }
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public:
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/* Operators containers @{ */
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eoOperatorFoundry< eoContinue<EOT> > continuators;
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eoOperatorFoundry< double > crossover_rates;
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eoOperatorFoundry< eoQuadOp<EOT> > crossovers;
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eoOperatorFoundry< double > mutation_rates;
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eoOperatorFoundry< eoMonOp<EOT> > mutations;
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eoOperatorFoundry< eoSelectOne<EOT> > selectors;
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eoOperatorFoundry< size_t > pop_sizes;
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eoOperatorFoundry< eoReplacement<EOT> > replacements;
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/* @} */
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/** instantiate and call the pre-selected algorithm.
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*/
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void operator()(eoPop<EOT>& pop)
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{
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assert(continuators.size() > 0); assert(this->at(continuators.index()) < continuators.size());
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assert( crossover_rates.size() > 0); assert(this->at( crossover_rates.index()) < crossover_rates.size());
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assert( crossovers.size() > 0); assert(this->at( crossovers.index()) < crossovers.size());
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assert( mutation_rates.size() > 0); assert(this->at( mutation_rates.index()) < mutation_rates.size());
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assert( mutations.size() > 0); assert(this->at( mutations.index()) < mutations.size());
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assert( selectors.size() > 0); assert(this->at( selectors.index()) < selectors.size());
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assert( pop_sizes.size() > 0); assert(this->at( pop_sizes.index()) < pop_sizes.size());
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assert(replacements.size() > 0); assert(this->at(replacements.index()) < replacements.size());
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// Crossover or clone
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double cross_rate = this->crossover_rate();
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eoProportionalOp<EOT> cross;
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// Cross-over that produce only one offspring,
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// made by wrapping the quad op (which produce 2 offsprings)
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// in a bin op (which ignore the second offspring).
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eoQuad2BinOp<EOT> single_cross(this->crossover());
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cross.add(single_cross, cross_rate);
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eoBinCloneOp<EOT> cross_clone;
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cross.add(cross_clone, 1 - cross_rate); // Clone
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// Mutation or clone
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double mut_rate = this->mutation_rate();
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eoProportionalOp<EOT> mut;
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mut.add(this->mutation(), mut_rate);
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eoMonCloneOp<EOT> mut_clone;
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mut.add(mut_clone, 1 - mut_rate); // FIXME TBC
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// Apply mutation after cross-over.
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eoSequentialOp<EOT> variator;
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variator.add(cross,1.0);
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variator.add(mut,1.0);
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// All variatiors
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double lambda = this->pop_size();
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eoGeneralBreeder<EOT> breeder(this->selector(), variator, lambda, /*as rate*/false);
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// Objective function calls counter
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eoEvalCounterThrowException<EOT> eval(_eval, _max_evals);
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eoPopLoopEval<EOT> pop_eval(eval);
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// Algorithm itself
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eoEasyEA<EOT> algo = eoEasyEA<EOT>(this->continuator(), pop_eval, breeder, this->replacement());
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// Restart wrapper
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eoAlgoPopReset<EOT> reset_pop(_init, pop_eval);
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eoGenContinue<EOT> restart_cont(_max_restarts);
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eoAlgoRestart<EOT> restart(eval, algo, restart_cont, reset_pop);
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try {
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restart(pop);
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} catch(eoMaxEvalException e) {
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// In case some solutions were not evaluated when max eval occured.
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eoPopLoopEval<EOT> pop_last_eval(_eval);
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pop_last_eval(pop,pop);
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}
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}
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/** Return an approximate name of the selected algorithm.
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*
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* @note: does not take into account parameters of the operators,
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* only show class names.
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*/
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std::string name()
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{
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std::ostringstream name;
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name << this->at(continuators.index()) << " (" << this->continuator().className() << ") + ";
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name << this->at(crossover_rates.index()) << " (" << this->crossover_rate().className() << ") + ";
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name << this->at(crossovers.index()) << " (" << this->crossover().className() << ") + ";
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name << this->at(mutation_rates.index()) << " (" << this->mutation_rate().className() << ") + ";
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name << this->at(mutations.index()) << " (" << this->mutation().className() << ") + ";
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name << this->at(selectors.index()) << " (" << this->selector().className() << ") + ";
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name << this->at(pop_sizes.index()) << " (" << this->pop_size().className() << ")";
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name << this->at(replacements.index()) << " (" << this->replacement().className() << ")";
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return name.str();
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}
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protected:
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eoEvalFunc<EOT>& _eval;
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eoInit<EOT>& _init;
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const size_t _max_evals;
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const size_t _max_restarts;
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public:
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eoContinue<EOT>& continuator()
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{
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assert(this->at(continuators.index()) < continuators.size());
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return continuators.instantiate(this->at(continuators.index()));
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}
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double& crossover_rate()
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{
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assert(this->at(crossover_rates.index()) < crossover_rates.size());
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return crossover_rates.instantiate(this->at(crossover_rates.index()));
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}
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eoQuadOp<EOT>& crossover()
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{
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assert(this->at(crossovers.index()) < crossovers.size());
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return crossovers.instantiate(this->at(crossovers.index()));
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}
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double& mutation_rate()
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{
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assert(this->at(mutation_rates.index()) < mutation_rates.size());
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return mutation_rates.instantiate(this->at(mutation_rates.index()));
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}
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eoMonOp<EOT>& mutation()
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{
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assert(this->at(mutations.index()) < mutations.size());
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return mutations.instantiate(this->at(mutations.index()));
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}
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eoSelectOne<EOT>& selector()
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{
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assert(this->at(selectors.index()) < selectors.size());
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return selectors.instantiate(this->at(selectors.index()));
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}
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size_t& pop_size()
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{
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assert(this->at(pop_sizes.index()) < pop_sizes.size());
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return pop_sizes.instantiate(this->at(pop_sizes.index()));
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}
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eoReplacement<EOT>& replacement()
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{
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assert(this->at(replacements.index()) < replacements.size());
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return replacements.instantiate(this->at(replacements.index()));
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}
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};
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#endif // _eoAlgoFoundryFastGA_H_
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@ -272,6 +272,8 @@ template<class EOT> class eoEasyEA: public eoAlgo<EOT>
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replace(_pop, offspring); // after replace, the new pop. is in _pop
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std::cout << _pop << std::endl;
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if (pSize > _pop.size())
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throw eoException("Population shrinking!");
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else if (pSize < _pop.size())
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@ -97,7 +97,8 @@ class eoCommaReplacement : public eoMergeReduce<EOT>
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virtual void operator()(eoPop<EOT>& _parents, eoPop<EOT>& _offspring)
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{
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// There must be more offsprings than parents, or else an exception will be raised
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assert( _offspring.size() >= _parents.size() );
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// Removed this assertion, which do not hold in some special case of singe indivudal algorithms.
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//assert( _offspring.size() >= _parents.size() );
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eoMergeReduce<EOT>::operator()( _parents, _offspring );
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}
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@ -106,6 +106,7 @@ public:
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for (size_t i = 0; i < rates.size(); ++i) {
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_pop.seekp(pos);
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do {
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// std::clog << "Before:" << _pop.offspring().size() << " offsprings" << std::endl;
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if (eo::rng.flip(rates[i])) {
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// try
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// {
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@ -126,6 +127,11 @@ public:
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if (!_pop.exhausted())
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++_pop;
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// std::clog << "After:" << _pop.offspring().size() << " offsprings" << std::endl;
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// std::clog << _pop.offspring() << std::endl;
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// std::clog << std::endl;
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}
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while (!_pop.exhausted());
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}
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@ -155,6 +161,7 @@ public:
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try
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{
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// std::clog << "\t" << ops[i]->className() << std::endl;
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(*ops[i])(_pop);
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++_pop;
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}
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@ -34,6 +34,7 @@
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// the operators
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#include "ga/eoBitOp.h"
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#include "ga/eoStandardBitMutation.h"
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// #include <ga/eoBitOpFactory.h> to be corrected - thanks someone!
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213
eo/src/ga/eoStandardBitMutation.h
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213
eo/src/ga/eoStandardBitMutation.h
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@ -0,0 +1,213 @@
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#ifndef _eoStandardBitMutation_h_
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#define _eoStandardBitMutation_h_
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#include "../utils/eoRNG.h"
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/** Standard bit mutation with mutation rate p:
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* choose k from the binomial distribution Bin(n,p) and apply flip_k(x).
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*
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* @ingroup Bitstrings
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* @ingroup Variators
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*/
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template<class EOT>
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class eoStandardBitMutation : public eoMonOp<EOT>
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{
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public:
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eoStandardBitMutation(double rate = 0.5) :
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_rate(rate),
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_nb(1),
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_bitflip(_nb)
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{}
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virtual bool operator()(EOT& chrom)
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{
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_nb = eo::rng.binomial(chrom.size(),_rate);
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// BitFlip operator is bound to the _nb reference,
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// thus one don't need to re-instantiate.
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return _bitflip(chrom);
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}
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protected:
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double _rate;
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unsigned _nb;
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eoDetSingleBitFlip<EOT> _bitflip;
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};
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/** Uniform bit mutation with mutation rate p:
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* choose k from the uniform distribution U(0,n) and apply flip_k(x).
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*
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* @ingroup Bitstrings
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* @ingroup Variators
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*/
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template<class EOT>
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class eoUniformBitMutation : public eoMonOp<EOT>
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{
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public:
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eoUniformBitMutation(double rate = 0.5) :
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_rate(rate),
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_nb(1),
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_bitflip(_nb)
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{}
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virtual bool operator()(EOT& chrom)
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{
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_nb = eo::rng.random(chrom.size());
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// BitFlip operator is bound to the _nb reference,
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// thus one don't need to re-instantiate.
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return _bitflip(chrom);
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}
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protected:
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double _rate;
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unsigned _nb;
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eoDetSingleBitFlip<EOT> _bitflip;
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};
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/** Conditional standard bit mutation with mutation rate p:
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* choose k from the binomial distribution Bin(n,p) until k >0
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* and apply flip_k(x).
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*
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* This is identical to sampling k from the conditional binomial
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* distribution Bin>0(n,p) which re-assigns the probability to sample
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* a 0 proportionally to all values i ∈ [1..n].
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*
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* @ingroup Bitstrings
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* @ingroup Variators
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*/
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template<class EOT>
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class eoConditionalBitMutation : public eoStandardBitMutation<EOT>
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{
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public:
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eoConditionalBitMutation(double rate = 0.5) :
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eoStandardBitMutation<EOT>(rate)
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{}
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virtual bool operator()(EOT& chrom)
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{
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assert(chrom.size()>0);
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this->_nb = eo::rng.binomial(chrom.size()-1,this->_rate);
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this->_nb++;
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// BitFlip operator is bound to the _nb reference,
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// thus one don't need to re-instantiate.
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return this->_bitflip(chrom);
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}
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};
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/** Shifted standard bit mutation with mutation rate p:
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* choose k from the binomial distribution Bin(n,p).
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* When k= 0, set k= 1. Apply flip_k(x).
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*
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* This is identical to sampling k from the conditional binomial
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* distribution Bin0→1(n,p) which re-assigns the probability to
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* sample a 0 to sampling k= 1.
|
||||
*
|
||||
* @ingroup Bitstrings
|
||||
* @ingroup Variators
|
||||
*/
|
||||
template<class EOT>
|
||||
class eoShiftedBitMutation : public eoStandardBitMutation<EOT>
|
||||
{
|
||||
public:
|
||||
eoShiftedBitMutation(double rate = 0.5) :
|
||||
eoStandardBitMutation<EOT>(rate)
|
||||
{}
|
||||
|
||||
virtual bool operator()(EOT& chrom)
|
||||
{
|
||||
assert(chrom.size()>0);
|
||||
this->_nb = eo::rng.binomial(chrom.size()-1,this->_rate);
|
||||
if(this->_nb == 0) {
|
||||
this->_nb = 1;
|
||||
}
|
||||
// BitFlip operator is bound to the _nb reference,
|
||||
// thus one don't need to re-instantiate.
|
||||
return this->_bitflip(chrom);
|
||||
}
|
||||
};
|
||||
|
||||
/** Mutation which size is sample in a gaussian.
|
||||
*
|
||||
* sample k from the normal distribution N(pn,σ^2)
|
||||
* and apply flip_k(x).
|
||||
*
|
||||
* From:
|
||||
* Furong Ye, Carola Doerr, and Thomas Back.
|
||||
* Interpolating local and global search by controllingthe variance of standard bit mutation.
|
||||
* In 2019 IEEE Congress on Evolutionary Computation(CEC), pages 2292–2299.
|
||||
*
|
||||
* In contrast to standard bit mutation, this operators allows to scale
|
||||
* the variance of the mutation strength independently of the mean.
|
||||
*
|
||||
* @ingroup Bitstrings
|
||||
* @ingroup Variators
|
||||
*/
|
||||
template<class EOT>
|
||||
class eoNormalBitMutation : public eoStandardBitMutation<EOT>
|
||||
{
|
||||
public:
|
||||
eoNormalBitMutation(double rate = 0.5, double variance = 1) :
|
||||
eoStandardBitMutation<EOT>(rate),
|
||||
_variance(variance)
|
||||
{}
|
||||
|
||||
virtual bool operator()(EOT& chrom)
|
||||
{
|
||||
this->_nb = eo::rng.normal(this->_rate * chrom.size(), _variance);
|
||||
if(this->_nb >= chrom.size()) {
|
||||
this->_nb = eo::rng.random(chrom.size());
|
||||
}
|
||||
// BitFlip operator is bound to the _nb reference,
|
||||
// thus one don't need to re-instantiate.
|
||||
return this->_bitflip(chrom);
|
||||
}
|
||||
|
||||
protected:
|
||||
double _variance;
|
||||
};
|
||||
|
||||
/** Fast mutation which size is sampled from an adaptive power law.
|
||||
*
|
||||
* From:
|
||||
* Benjamin Doerr, Huu Phuoc Le, Régis Makhmara, and Ta Duy Nguyen.
|
||||
* Fast genetic algorithms.
|
||||
* In Proc. of Genetic and Evolutionary Computation Conference (GECCO’17), pages 777–784.ACM, 2017.
|
||||
*
|
||||
* @ingroup Bitstrings
|
||||
* @ingroup Variators
|
||||
*/
|
||||
template<class EOT>
|
||||
class eoFastBitMutation : public eoStandardBitMutation<EOT>
|
||||
{
|
||||
public:
|
||||
eoFastBitMutation(double rate = 0.5, double beta = 1.5) :
|
||||
eoStandardBitMutation<EOT>(rate),
|
||||
_beta(beta)
|
||||
{
|
||||
assert(beta > 1);
|
||||
}
|
||||
|
||||
virtual bool operator()(EOT& chrom)
|
||||
{
|
||||
this->_nb = powerlaw(chrom.size(),_beta);
|
||||
// BitFlip operator is bound to the _nb reference,
|
||||
// thus one don't need to re-instantiate.
|
||||
return this->_bitflip(chrom);
|
||||
}
|
||||
|
||||
protected:
|
||||
|
||||
double powerlaw(unsigned n, double beta)
|
||||
{
|
||||
double cnb = 0;
|
||||
for(unsigned i=1; i<n; ++i) {
|
||||
cnb += std::pow(i,-beta);
|
||||
}
|
||||
return eo::rng.powerlaw(0,n,beta) / cnb;
|
||||
}
|
||||
|
||||
double _beta;
|
||||
};
|
||||
|
||||
#endif // _eoStandardBitMutation_h_
|
||||
|
|
@ -216,7 +216,7 @@ public :
|
|||
return uniform() < bias;
|
||||
}
|
||||
|
||||
/** Sample in a binomial dsitribution of size n and probability p.
|
||||
/** Sample in a binomial distribution of size n and probability p.
|
||||
|
||||
FIXME most naive algorithm, one should really use a rejection algorithm.
|
||||
*/
|
||||
|
|
@ -229,6 +229,18 @@ public :
|
|||
return x;
|
||||
}
|
||||
|
||||
/** Sample in a power law distribution
|
||||
*/
|
||||
double powerlaw(double min, double max, double gamma)
|
||||
{
|
||||
double x = uniform(min,max);
|
||||
return std::pow(
|
||||
x * (std::pow(max,-gamma+1) - std::pow(min,-gamma+1))
|
||||
+ std::pow(min,-gamma+1.0),
|
||||
1.0/(-gamma + 1.0)
|
||||
);
|
||||
}
|
||||
|
||||
/** Gaussian deviate
|
||||
|
||||
Zero mean Gaussian deviate with standard deviation 1.
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue