public double Evaluate( double x, double y ) {
Engine engine = new Engine();
engine.SetVariable( "x", x );
engine.SetVariable( "y", y );
double res = root.Evaluate( engine );
return res;
}
public void Tick() {
Engine engine = new Engine();
MathFunction clone = null;
clone = (MathFunction)root.Clone();
clone.Mutate();
if( clone.ToString() == root.ToString() )
return;
double totNewError = 0;
double totOldError = 0;
foreach( Case currentCase in problem.Cases ) {
engine.SetVariable( "x", currentCase.X );
engine.SetVariable( "y", currentCase.Y );
double newResult = clone.Evaluate( engine );
double oldResult = root.Evaluate( engine );
double newError = Math.Abs( currentCase.Result - newResult );
double oldError = Math.Abs( currentCase.Result - oldResult );
totNewError += newError;
totOldError += oldError;
}
//its a good match
if( totNewError < totOldError ||
( ( clone.ToString().Length < root.ToString().Length ) && totNewError < totOldError + double.Epsilon ) ) {
//Console.WriteLine(clone.ToString ());
// Console.WriteLine(totNewError.ToString("0.0000000000") + " " + clone.ToString());
root = clone;
this.Error = totNewError;
}
}
