Individual (Jenes)

java.lang.Object
- jenes.population.Individual<T>

Type Parameters:
T - The type of chromosome.

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, java.lang.Comparable<Individual<T>>
```
public final class Individual<T extends Chromosome>
extends java.lang.Object
implements java.lang.Cloneable, java.io.Serializable, java.lang.Comparable<Individual<T>>
```
Individual represents a solution processed by a genetic algorithm. It is made of a Chromosome representing its genoma, and a score representing its fitness. To be valid, the score must be non-negative.
A key point is how to compare individuals. There two ways in comparing individuals: by fitness and chromosome. The compareTo(Individual) method tests if scores are equal or which one is bigger regardless at their genoma. The equals(Individual) methods compares the chromosome. In order to gain efficiency in comparing individuals, the isSameChromosomeSameFitness() property is used to shortcut the procedure. If this property is true, equals returns true according to the score, thus avoiding to perform an expensive chromosome comparison. Indeed, by setting the sameChromosomeSameFitness property to true, we assume that is not possible to have two different chromosome with the same score. Appliability fo this property depends on the problem and search landscape characteristics. Obviously, we assume that individuals with the same chromosome must show the fitness value.
In complex search spaces, not every solution is feasible. The solution feasability is controlled by the legal property.

Since:

1.0

Version:

2.0

See Also:
Population, Chromosome, Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class Individual.Statistics<T extends Chromosome>
This class provides some basic statistics regarding an Individual .

Nested Classes
Modifier and Type	Class and Description
`static class`	`Individual.Statistics<T extends Chromosome>` This class provides some basic statistics regarding an `Individual` .

Field Summary

Fields
Modifier and Type Field and Description

static int UNRANKED
the default individual's rank

Fields
Modifier and Type	Field and Description
`static int`	`UNRANKED` the default individual's rank

Constructor Summary

Constructors
Constructor and Description
`Individual()` Creates an `Individual` with no genome.
`Individual(Individual<T> ind)` Constructs a new `Individual` as a copy of another `Individual`.
`Individual(int n, T chromosome)` Creates an `Individual` with a specific chromosome and a number of scores.
`Individual(T chromosome, double... score)` Creates an `Individual` with the specified genome and a given score array(fitness value).

Method Summary

Methods
Modifier and Type	Method and Description
`Individual<T>`	`clone()` Returns a cloned instance of this class
`int`	`compareTo(Individual<T> ind)` Compares this individual with the specified individual.
`boolean`	`equals(Individual<T> ind)` Indicates whether the other individual is "equal to" this one.
`double[]`	`getAllScores()` Returns all scores
`T`	`getChromosome()` Returns the `Individual`'s genome
`int`	`getChromosomeLength()` Returns the chromosome's length
`int`	`getNumOfObjectives()` Returns the number of objectivies for which this `Individual` is evaluated
`Population<T>`	`getPopulation()` Return the `Population` that contains this `Individual`
`int`	`getRank()` Returns the individual's rank
`double`	`getScore()` Returns the `Individual`'s fitness value This score is meaningful only if `isEvaluated()` returns true.
`double`	`getScore(int i)` Return the score at a specific position
`int`	`getSpeciem()` Returns the subpopulation the individual belongs to
`Individual.Statistics<T>`	`getStatistics()` Returns the `Individual.Statistics` of this `Individual`
`boolean`	`isEvaluated()` Tests if the `Individual` is evaluated
`boolean`	`isLegal()` Tests if this Individual is a legal individual i.e is a feasible solution.
`static boolean`	`isSameChromosomeSameFitness()` Returns true if individual with the same chromosome must have also the same fitness (if evaluated), false otherwise
`void`	`randomize()` Randomizes the genome (chromosome) of this `Individual`
`void`	`resetScores(int m)` Reset the array of scores by setting each value to `Double.NaN`.
`void`	`setAs(Individual<T> individual)` Sets this `Individual` as the specified one.
`void`	`setAs(Individual<T> individual, boolean full)` Sets this `Individual`'s genome equal to the specified `Individual`'s one
`void`	`setChromosome(T chromosome)` Sets the `Individual`'s genome
`void`	`setLegal(boolean legal)` Sets the legal state of this individual
`void`	`setNotEvaluated()` Sets this individual as not evaluated.
`static void`	`setSameChromosomeSameFitness(boolean sameChromosomeSameFitness)` Set to true if individual with the same chromosome must have also the same fitness (if evaluated), false otherwise
`void`	`setScore(double... score)` Sets the `Individual`'s fitness value.
`void`	`setScore(double score, int i)` Set the score at specific position and check if this `Individual` is evaluated
`void`	`setSpeciem(int speciem)` Sets the subpopulation the individual belongs to
`java.lang.String`	`toCompleteString()` Returns a full textual representation of this Individual
`java.lang.String`	`toString()`

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - UNRANKED
```
public static final int UNRANKED
```
    the default individual's rank
    
    See Also:
    Constant Field Values
- Constructor Detail
  - Individual
```
public Individual()
```
    Creates an Individual with no genome.
  - Individual
```
public Individual(int n,
          T chromosome)
```
    Creates an Individual with a specific chromosome and a number of scores.
    
    Parameters:
    n - number of scores
    chromosome - individual's chromosome
  - Individual
```
public Individual(T chromosome,
          double... score)
```
    Creates an Individual with the specified genome and a given score array(fitness value).
    
    Parameters:
    chromosome - individual's genome
    score - individual's score array
  - Individual
```
public Individual(Individual<T> ind)
```
    Constructs a new Individual as a copy of another Individual.
    
    Parameters:
    ind - the source Individual.
- Method Detail
  - getPopulation
```
public final Population<T> getPopulation()
```
    Return the Population that contains this Individual
    
    Returns:
    individual's population
  - getChromosome
```
public final T getChromosome()
```
    Returns the Individual's genome
    
    Returns:
    the individual's genome
  - setChromosome
```
public final void setChromosome(T chromosome)
```
    Sets the Individual's genome
    
    Parameters:
    chromosome - the Individual's genome
  - getNumOfObjectives
```
public final int getNumOfObjectives()
```
    Returns the number of objectivies for which this Individual is evaluated
    
    Returns:
    the score array's lengh
  - getScore
```
public final double getScore()
```
    Returns the Individual's fitness value This score is meaningful only if isEvaluated() returns true. Otherwise the score is equal to Double.NaN.
    
    Returns:
    the Individual's fitness value
  - getScore
```
public final double getScore(int i)
```
    Return the score at a specific position
    
    Parameters:
    i - index of array's score
    
    Returns:
    score
  - getAllScores
```
public final double[] getAllScores()
```
    Returns all scores
    
    Returns:
    the array of scores
  - resetScores
```
public final void resetScores(int m)
```
    Reset the array of scores by setting each value to Double.NaN. If the value given as argument is different from the actual length of scores' array, a new array is created.
    
    Parameters:
    m - lenght of scores' array
  - setScore
```
public final void setScore(double... score)
```
    Sets the Individual's fitness value.
    
    Parameters:
    score - the Individual's fitness value
  - setScore
```
public final void setScore(double score,
            int i)
```
    Set the score at specific position and check if this Individual is evaluated
    
    Parameters:
    score - value of score
    i - array's index
  - setNotEvaluated
```
public final void setNotEvaluated()
```
    Sets this individual as not evaluated.
  - getRank
```
public int getRank()
```
    Returns the individual's rank
    
    Returns:
    the individual's rank
  - getSpeciem
```
public int getSpeciem()
```
    Returns the subpopulation the individual belongs to
    
    Returns:
    the subpopulation id
  - setSpeciem
```
public void setSpeciem(int speciem)
```
    Sets the subpopulation the individual belongs to
    
    Parameters:
    speciem - - the subpopulation id
  - clone
```
public final Individual<T> clone()
```
    Returns a cloned instance of this class
    
    Overrides:
    
    clone in class java.lang.Object
    
    Returns:
    a clone of this Individual
  - randomize
```
public final void randomize()
```
    Randomizes the genome (chromosome) of this Individual
  - setAs
```
public final void setAs(Individual<T> individual)
```
    Sets this Individual as the specified one.
    
    Parameters:
    individual - the model individual
  - setAs
```
public final void setAs(Individual<T> individual,
         boolean full)
```
    Sets this Individual's genome equal to the specified Individual's one
    
    Parameters:
    individual - the instance to copy as
  - isEvaluated
```
public final boolean isEvaluated()
```
    Tests if the Individual is evaluated
    
    Returns:
    true if the Individual is evaluated; false otherwise
  - toCompleteString
```
public final java.lang.String toCompleteString()
```
    Returns a full textual representation of this Individual
    
    Returns:
    representation
  - toString
```
public final java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
  - isLegal
```
public final boolean isLegal()
```
    Tests if this Individual is a legal individual i.e is a feasible solution.
    
    Returns:
    true if this individual is a legal solution; flase otherwise.
  - setLegal
```
public final void setLegal(boolean legal)
```
    Sets the legal state of this individual
    
    Parameters:
    legal - true if legal; false otherwise.
  - compareTo
```
public final int compareTo(Individual<T> ind)
```
    Compares this individual with the specified individual. Returns a negative, zero or positive value as the individual is lesser than, equal to, or greater than the specified individual. The comparison is based on the chromosome score. Note: this class has a natural ordering that is inconsistent with equals.
    
    Specified by:
    
    compareTo in interface java.lang.Comparable<Individual<T extends Chromosome>>
    
    Parameters:
    ind - the individual to be compared.
  - equals
```
public final boolean equals(Individual<T> ind)
```
    Indicates whether the other individual is "equal to" this one. i.e if they have the same fitness and the same chromosome
    
    Parameters:
    ind - the reference individual with which to compare.
    
    Returns:
    true if the individual has the same chromosome and score as the other; false otherwise.
  - getChromosomeLength
```
public final int getChromosomeLength()
```
    Returns the chromosome's length
    
    Returns:
    the chromosome's length
  - isSameChromosomeSameFitness
```
public static final boolean isSameChromosomeSameFitness()
```
    Returns true if individual with the same chromosome must have also the same fitness (if evaluated), false otherwise
    
    Returns:
    the sameChromosomeSameFitness field value
  - setSameChromosomeSameFitness
```
public static final void setSameChromosomeSameFitness(boolean sameChromosomeSameFitness)
```
    Set to true if individual with the same chromosome must have also the same fitness (if evaluated), false otherwise
    
    Parameters:
    sameChromosomeSameFitness - the sameChromosomeSameFitness value
  - getStatistics
```
public Individual.Statistics<T> getStatistics()
```
    Returns the Individual.Statistics of this Individual
    
    Returns:
    the Individual.Statistics object

Class Individual<T extends Chromosome>

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

UNRANKED

Constructor Detail

Individual

Individual

Individual

Individual

Method Detail

getPopulation

getChromosome

setChromosome

getNumOfObjectives

getScore

getScore

getAllScores

resetScores

setScore

setScore

setNotEvaluated

getRank

getSpeciem

setSpeciem

clone

randomize

setAs

setAs

isEvaluated

toCompleteString

toString

isLegal

setLegal

compareTo

equals

getChromosomeLength

isSameChromosomeSameFitness

setSameChromosomeSameFitness

getStatistics