FitnessEvaluation.externalInterpreters.SymbolicRegression
Class SymRegFunkBSF

java.lang.Object
  extended by FitnessEvaluation.externalInterpreters.SymbolicRegression.SymRegFunkBSF

public abstract class SymRegFunkBSF
extends java.lang.Object

help class for SymbolicRegression.java

Author:
jonatan

Constructor Summary
SymRegFunkBSF()
          Creates a new instance of SymRegFunkBSF
 
Method Summary
 double cos(double x)
          Trigonometric cosine function
 double div(double n, double d)
          Protected division.
 double exp(double x)
          Returns Euler's number e raised to the power of a double value.
abstract  double expr(double X)
          Expression to evaluate
 double fun(double x)
          Hardcoded quadratic target function
 double getFitness()
          Calculating the fitness as the sum of errors.
 double inv(double x)
          Method for inverting x.
 double log(double x)
          Natural logarithm
 double pow(double x, double y)
          Method for x to the power of y
 double sin(double x)
          Trigonometric sine function
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

SymRegFunkBSF

public SymRegFunkBSF()
Creates a new instance of SymRegFunkBSF

Method Detail

expr

public abstract double expr(double X)
Expression to evaluate

Parameters:
X - point
Returns:
value

getFitness

public double getFitness()
Calculating the fitness as the sum of errors. Deterministically picks 20 points in [-1,1) Minimizing, 0 is best

Returns:
value as sum of errors

fun

public double fun(double x)
Hardcoded quadratic target function

Parameters:
x - value
Returns:
target function value

inv

public double inv(double x)
Method for inverting x. Returns 1 if x = 0

Parameters:
x - value to invert
Returns:
inverted value

pow

public double pow(double x,
                  double y)
Method for x to the power of y

Parameters:
x - base
y - exponent
Returns:
x^y

div

public double div(double n,
                  double d)
Protected division. If d = 0. Return Double.MAX_VALUE. If n = 0 return 0

Parameters:
n - dividend
d - divisor
Returns:
quotient

sin

public double sin(double x)
Trigonometric sine function

Parameters:
x - angle in radians
Returns:
sine of argument

cos

public double cos(double x)
Trigonometric cosine function

Parameters:
x - angle in radians
Returns:
cosine of argument

exp

public double exp(double x)
Returns Euler's number e raised to the power of a double value.

Parameters:
x - exponent to raise e to
Returns:
e^a

log

public double log(double x)
Natural logarithm

Parameters:
x - value to take the logarithm of
Returns:
log(x)