math.numerics
Class Util

java.lang.Object
  math.numerics.Util

public final class Util
extends java.lang.Object

A utility class for numerical analysis. This class cannot be subclassed or instantiated because all methods are static.

Version:

1.0

Author:

Wolfgang Christian

Field Summary

static double

defaultNumericalPrecision The default precision for numerical analysis.

Method Summary

static int	checkSorting(double[] array) Checks if an array is sorted.
static double	computeAverage(double[] array, int start, int num) Computes the average value of a subset of an array.
static Function	constantFunction(double _c) Creates a function having a constant value.
static double	evalMath(java.lang.String str) Evalautes a mathematical expression without variables.
static double[][]	functionFill(Function f, double start, double stop, double[][] data) Fills an array with f(x) values.
static double[][]	functionFill(Function f, double start, double stop, int n) Fills an array with f(x) values.
static double[]	getDomain(Function f, double a, double b, int n)
static double	relativePrecision(double epsilon, double result) Method relativePrecision

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

defaultNumericalPrecision

public static final double defaultNumericalPrecision

The default precision for numerical analysis.

Method Detail

relativePrecision

public static double relativePrecision(double epsilon,
                                       double result)

Method relativePrecision

Parameters:

epsilon - the absolute error

result - the result

Returns:

the relative error

checkSorting

public static int checkSorting(double[] array)

Checks if an array is sorted. Returns: Positive integer if array is sorted in increasing value. Negative integer if array is sorted in decreasing value. Zero if array is not sorted.

Parameters:

array - double[]

Returns:

int 1,0,-1 based on sorting

getDomain

public static double[] getDomain(Function f,
                                 double a,
                                 double b,
                                 int n)

functionFill

public static double[][] functionFill(Function f,
                                      double start,
                                      double stop,
                                      int n)

Fills an array with f(x) values.

Parameters:

f - Function

start - double

stop - double

n - int

Returns:

double[][]

functionFill

public static double[][] functionFill(Function f,
                                      double start,
                                      double stop,
                                      double[][] data)

Fills an array with f(x) values.

Parameters:

f - Function

start - double

stop - double

data - double[][]

Returns:

double[][]

computeAverage

public static double computeAverage(double[] array,
                                    int start,
                                    int num)

Computes the average value of a subset of an array.

Parameters:

array - the data to be averaged

start - the index of the first point to be averaged

num - the total number of points to be averaged

Returns:

constantFunction

public static Function constantFunction(double _c)

Creates a function having a constant value.

Parameters:

_c -

Returns:

evalMath

public static double evalMath(java.lang.String str)

Evalautes a mathematical expression without variables.

Parameters:

str - String

Returns:

double