VImage
VImage::new_from_image( std::vector<double> pixel )
{
VImage onepx = VImage::black( 1, 1,
VImage::option()->set( "bands", bands() ) );
onepx = onepx.linear( to_vectorv( 1, 1.0 ), pixel ).cast( format() );
VImage big = onepx.embed( 0, 0, width(), height(),
VImage::option()->set( "extend", VIPS_EXTEND_COPY ) );
big = big.copy(
VImage::option()->
set( "interpretation", interpretation() )->
set( "xres", xres() )->
set( "yres", yres() )->
set( "xoffset", xres() )->
set( "yoffset", yres() ) );
return( big );
}
/**
* Here we evaluate the fitness of an individual.
*/
double CNFFitnessEvaluator::evaluate( void *individual )
{
// We store the last evaluated individual in a
// cache. This way, if the new individual is a copy
// of the last one (wich usually happens after a number
// of generations, when the population converges), we will
// save a lot of time by not having to re-evaluate everything.
// Here we are checking wether this individual is equal to
// the last one.
if ( previous != NULL )
{
// Copy the individual to a buffer.
memcpy( current, individual, arraySize );
// zero-out the remaining bits of the last byte, just to be sure that
// the unused bits won't make the memcmp call fail
int lastBits = stringSize % INT_BITSIZE;
if ( lastBits > 0 )
{
int pattern = ( 1 << lastBits ) - 1;
current[arraySize - 1] &= pattern;
}
// Compare the current individual with the last one in the cache
// If they are the same we return the stored evaluation.
if ( memcmp( current, previous, arraySize ) == 0 )
{
// cout << "Cache hit!" << endl;
return lastEval;
}
}
else
{
current = new int[arraySize];
previous = new int[arraySize];
}
// Copy the current individual to the cache.
// We zero-out the remaining bits of the last byte, just to be sure
// that the unused bits won't make the comparision fail.
memcpy( previous, individual, arraySize );
int lastBits = stringSize % INT_BITSIZE;
if ( lastBits > 0 )
{
int pattern = ( 1 << lastBits ) - 1;
current[arraySize - 1] &= pattern;
}
// Now let's evaluate this individual. We need an interpretation
// object that will wrap the actual bits.
Interpretation interpretation( stringSize );
interpretation.assign( individual, stringSize );
// Get the number of satisfied clauses.
int nSatisfied = 0;
for ( int i = 0; i < formula.getNumClauses(); i++ )
{
if ( formula.getClauseValue( i, interpretation ) == true )
{
nSatisfied++;
}
}
// If this individual has all clauses satisfied, we set a flag
// indicating that it is the result.
if ( nSatisfied == formula.getNumClauses() )
{
bLastIsResult = true;
}
else
{
bLastIsResult = false;
}
// Save the number of satisfied clauses in the cache.
lastEval = nSatisfied;
// The number of satisfied clauses is this individual's fitness.
double fitness = nSatisfied;
return fitness;
}
int testDualEncoding( int argc, char **argv )
{
Random::s_randomize();
CNFFormula formula;
SATLIBParser parser;
bool res = parser.open( "tests/satlib2.txt" );
if ( res == false )
{
cout << "Mal, sap�o" << endl;
return 1;
}
formula = parser.getFormula();
DualEncodingSAT2CSP *enc = DualEncodingSAT2CSP::create();
enc->setFormula( &formula );
CSPProblem *problem = enc->getProblem();
int numVars = problem->getNumVars();
int numConstraints = problem->getConstraintList()->getNumConstraints();
cout << "Problem has " << numVars << " variables, " << " and " << numConstraints << " constraints." << endl;
Interpretation interpretation( formula.getNumVars() );
CSPInterpretation cspInterpretation( problem->getNumVars() );
AntSolver solver;
solver.setAlpha( 2 );
solver.setBeta( 10 );
solver.setMaxPheromone( 10 );
solver.setMinPheromone( 1 );
solver.setNumAnts( 8 );
solver.setProblem( problem );
solver.setRo( 0.99 );
res = solver.solve( 100 );
cout << res << endl;
if ( res == false )
{
cout << "Unable to solve with ant solver!!!" << endl;
return 1;
}
cout << "Solved with ant solver" << endl;
cspInterpretation = solver.getResult();
int i;
for ( i = 0; i < problem->getNumVars(); i++ )
{
int var1value = cspInterpretation.getVariableValue( i );
BasicCSPVariableValue* value1 = (BasicCSPVariableValue *)problem->getDomainList()->getDomain( i )->getValue( var1value );
cout << "Var " << i << " = " << value1->getValue() << endl;
}
res = enc->getSATInterpretation( cspInterpretation, interpretation );
if ( res == false )
{
cout << "Unable to retrieve the SAT interpretaiton" << endl;
return 2;
}
if ( formula.getNumSatisfiedClauses( interpretation ) != formula.getNumClauses() )
{
cout << "Formula not satisfied!" << endl;
return 3;
}
return 0;
}
