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SUMMARY: INNER | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Object | +--ec.gp.koza.KozaFitness
KozaFitness is a Fitness which stores an individual's fitness as described in Koza I. Well, almost. In KozaFitness, standardized fitness and raw fitness are considered the same (there are different methods for them, but they return the same thing). Standardized fitness ranges from 0.0 inclusive (the best) to infinity exclusive (the worst). Adjusted fitness converts this, using the formula adj_f = 1/(1+f), into a scale from 0.0 exclusive (worst) to 1.0 inclusive (best). While it's the standardized fitness that is stored, it is the adjusted fitness that is printed out. This is all just convenience stuff anyway; selection methods generally don't use these fitness values but instead use the betterThan and equalTo methods.
Default Base
gp.koza.fitness
Field Summary | |
protected float |
fitness
This ranges from 0 (best) to infinity (worst). |
static java.lang.String |
FITNESS_PREAMBLE
|
int |
hits
This auxillary measure is used in some problems for additional information. |
static java.lang.String |
P_KOZAFITNESS
|
Fields inherited from interface ec.Fitness |
P_FITNESS |
Constructor Summary | |
KozaFitness()
|
Method Summary | |
float |
adjustedFitness()
Returns the adjusted fitness metric, which recasts the fitness to the half-open interval (0,1], where 1 is ideal and 0 is worst. |
boolean |
betterThan(Fitness _fitness)
Should return true if this fitness is clearly better than _fitness; You may assume that _fitness is of the same class as yourself. |
Parameter |
defaultBase()
Returns the default base for this prototype. |
boolean |
equivalentTo(Fitness _fitness)
Should return true if this fitness is in the same equivalence class as _fitness, that is, neither is clearly bettter or worse than the other. |
float |
fitness()
Returns the adjusted fitness metric, which recasts the fitness to the half-open interval (0,1], where 1 is ideal and 0 is worst. |
boolean |
isIdealFitness()
Should return true if this is a good enough fitness to end the run |
void |
printFitness(EvolutionState state,
int log,
int verbosity)
Should print the fitness out in a computer-readable fashion, using state.output.println(...,verbosity,log). |
void |
printFitness(EvolutionState state,
int thread,
java.io.PrintWriter writer)
Should print the fitness out in a computer-readable fashion, using state.output.println(...,verbosity,log). |
void |
printFitnessForHumans(EvolutionState state,
int log,
int verbosity)
Should print the fitness out in a pleasing way to humans, using state.output.println(...,verbosity,log) |
java.lang.Object |
protoClone()
Creates a new individual cloned from a prototype, and suitable to begin use in its own evolutionary context. |
java.lang.Object |
protoCloneSimple()
This should be implemented in a the top-level Prototype ONLY; in fact, it should probably be declared final. |
float |
rawFitness()
Returns the raw fitness metric. |
void |
readFitness(EvolutionState state,
int thread,
java.io.LineNumberReader reader)
Reads in the fitness from a form printed by printFitness(). |
void |
setFitness(EvolutionState state,
float _f)
|
void |
setup(EvolutionState state,
Parameter base)
Sets up the object by reading it from the parameters stored in state, built off of the parameter base base. |
float |
standardizedFitness()
Returns the standardized fitness metric, which is the same as the raw fitness metric in this scheme. |
Methods inherited from class java.lang.Object |
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait |
Field Detail |
public static final java.lang.String P_KOZAFITNESS
public static final java.lang.String FITNESS_PREAMBLE
protected float fitness
public int hits
Constructor Detail |
public KozaFitness()
Method Detail |
public Parameter defaultBase()
public java.lang.Object protoClone() throws java.lang.CloneNotSupportedException
The question here is whether or not this means to perform a "deep" or "light" ("shallow") clone, or something in-between. You may need to deep-clone parts of your object rather than simply copying their references, depending on the situation:
Implementations.
public Object protoClone() throws CloneNotSupportedException
{
return super.clone();
}
public Object protoClone() throws CloneNotSupportedException
{
myobj = (MyObject) (super.clone());
// put your deep-cloning code here...
// ...you should use protoClone and not
// protoCloneSimple to clone subordinate objects...
return myobj;
}
public Object protoClone() throws CloneNotSupportedException
{
MyObject myobj = (MyObject)(super.protoClone());
// put your deep-cloning code here...
// ...you should use protoClone and not
// protoCloneSimple to clone subordinate objects...
return myobj;
}
If you know that your superclasses will never change their protoClone() implementations, you might try inlining them in your overridden protoClone() method. But this is dangerous (though it yields a small net increase).
In general, you want to keep your deep cloning to an absolute minimum, so that you don't have to call protoClone() but one time.
The approach taken here is the fastest that I am aware of while still permitting objects to be specified at runtime from a parameter file. It would be faster to use the "new" operator; but that would require hard-coding that we can't do. Although using java.lang.Object.clone() entails an extra layer that deals with stripping away the "protected" keyword and also wrapping the exception handling (which is a BIG hit, about three times as slow as using "new"), it's still MUCH faster than using java.lang.Class.newInstance(), and also much faster than rolling our own Clone() method.
public final java.lang.Object protoCloneSimple()
public final Object protoCloneSimple()
{
try { return protoClone(); }
catch (CloneNotSupportedException e)
{ throw new InternalError(); } // never happens
}
public final void setFitness(EvolutionState state, float _f)
public final float fitness()
public final float rawFitness()
public final float standardizedFitness()
public final float adjustedFitness()
public final void setup(EvolutionState state, Parameter base)
For prototypes, setup(...) is typically called once for the prototype instance; cloned instances do not receive the setup(...) call. setup(...) may be called more than once; the only guarantee is that it will get called at least once on an instance or some "parent" object from which it was ultimately cloned.
public final boolean isIdealFitness()
public final boolean equivalentTo(Fitness _fitness)
public final boolean betterThan(Fitness _fitness)
public final void printFitness(EvolutionState state, int log, int verbosity)
public final void printFitness(EvolutionState state, int thread, java.io.PrintWriter writer)
public final void printFitnessForHumans(EvolutionState state, int log, int verbosity)
public final void readFitness(EvolutionState state, int thread, java.io.LineNumberReader reader) throws java.io.IOException, java.lang.CloneNotSupportedException
|
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