//----------------------------------------------------------------------------- // FirstBitEA.cpp //----------------------------------------------------------------------------- //* // Still an instance of a VERY simple Bitstring Genetic Algorithm // (see FirstBitGA.cpp) but now with Breeder - and Combined Ops // //----------------------------------------------------------------------------- #ifdef HAVE_CONFIG_H #include #endif // standard includes #include // runtime_error #include // cout // the general include for eo #include #include // Use functions from namespace std using namespace std; // REPRESENTATION //----------------------------------------------------------------------------- // define your individuals typedef eoBit Indi; // A bitstring with fitness double // EVALFUNC //----------------------------------------------------------------------------- // a simple fitness function that computes the number of ones of a bitstring // Now in a separate file, and declared as binary_value(const vector &) #include "binary_value.h" // GENERAL //----------------------------------------------------------------------------- void main_function(int /*argc*/, char **/*argv*/) { // PARAMETRES const unsigned int SEED = 42; // seed for random number generator const unsigned int T_SIZE = 3; // size for tournament selection const unsigned int VEC_SIZE = 8; // Number of bits in genotypes const unsigned int POP_SIZE = 20; // Size of population const unsigned int MAX_GEN = 500; // Maximum number of generation before STOP const unsigned int MIN_GEN = 10; // Minimum number of generation before ... const unsigned int STEADY_GEN = 50; // stop after STEADY_GEN gen. without improvelent const double P_CROSS = 0.8; // Crossover probability const double P_MUT = 1.0; // mutation probability const double P_MUT_PER_BIT = 0.01; // internal probability for bit-flip mutation // some parameters for chosing among different operators const double onePointRate = 0.5; // rate for 1-pt Xover const double twoPointsRate = 0.5; // rate for 2-pt Xover const double URate = 0.5; // rate for Uniform Xover const double bitFlipRate = 0.5; // rate for bit-flip mutation const double oneBitRate = 0.5; // rate for one-bit mutation // GENERAL ////////////////////////// // Random seed ////////////////////////// //reproducible random seed: if you don't change SEED above, // you'll aways get the same result, NOT a random run rng.reseed(SEED); // EVAL ///////////////////////////// // Fitness function //////////////////////////// // Evaluation: from a plain C++ fn to an EvalFunc Object // you need to give the full description of the function eoEvalFuncPtr& > eval( binary_value ); // INIT //////////////////////////////// // Initilisation of population //////////////////////////////// // based on boolean_generator class (see utils/eoRndGenerators.h) eoUniformGenerator uGen; eoInitFixedLength random(VEC_SIZE, uGen); // Initialization of the population eoPop pop(POP_SIZE, random); // and evaluate it in one loop apply(eval, pop); // STL syntax // OUTPUT // sort pop before printing it! pop.sort(); // Print (sorted) intial population (raw printout) cout << "Initial Population" << endl; cout << pop; // ENGINE ///////////////////////////////////// // selection and replacement //////////////////////////////////// // SELECT // The robust tournament selection eoDetTournamentSelect selectOne(T_SIZE); // T_SIZE in [2,POP_SIZE] // is now encapsulated in a eoSelectPerc (entage) eoSelectPerc select(selectOne);// by default rate==1 // REPLACE // And we now have the full slection/replacement - though with // no replacement (== generational replacement) at the moment :-) eoGenerationalReplacement replace; // OPERATORS ////////////////////////////////////// // The variation operators ////////////////////////////////////// // CROSSOVER // 1-point crossover for bitstring eo1PtBitXover xover1; // uniform crossover for bitstring eoUBitXover xoverU; // 2-pots xover eoNPtsBitXover xover2(2); // Combine them with relative rates eoPropCombinedQuadOp xover(xover1, onePointRate); xover.add(xoverU, URate); xover.add(xover2, twoPointsRate); // MUTATION // standard bit-flip mutation for bitstring eoBitMutation mutationBitFlip(P_MUT_PER_BIT); // mutate exactly 1 bit per individual eoDetBitFlip mutationOneBit; // Combine them with relative rates eoPropCombinedMonOp mutation(mutationBitFlip, bitFlipRate); mutation.add(mutationOneBit, oneBitRate, true); // The operators are encapsulated into an eoTRansform object eoSGATransform transform(xover, P_CROSS, mutation, P_MUT); // STOP // CHECKPOINT ////////////////////////////////////// // termination conditions: use more than one ///////////////////////////////////// // stop after MAX_GEN generations eoGenContinue genCont(MAX_GEN); // do MIN_GEN gen., then stop after STEADY_GEN gen. without improvement eoSteadyFitContinue steadyCont(MIN_GEN, STEADY_GEN); // stop when fitness reaches a target (here VEC_SIZE) eoFitContinue fitCont(VEC_SIZE); // do stop when one of the above says so eoCombinedContinue continuator(genCont); continuator.add(steadyCont); continuator.add(fitCont); // GENERATION ///////////////////////////////////////// // the algorithm //////////////////////////////////////// // Easy EA requires // selection, transformation, eval, replacement, and stopping criterion eoEasyEA gga(continuator, eval, select, transform, replace); // Apply algo to pop - that's it! cout << "\n Here we go\n\n"; gga(pop); // OUTPUT // Print (sorted) intial population pop.sort(); cout << "FINAL Population\n" << pop << endl; // GENERAL } // A main that catches the exceptions int main(int argc, char **argv) { try { main_function(argc, argv); } catch(exception& e) { cout << "Exception: " << e.what() << '\n'; } return 1; }