de.torstennahm.integrate.quadratureformula
Class QuadratureFormula

java.lang.Object
  de.torstennahm.integrate.quadratureformula.QuadratureFormula

public class QuadratureFormula
extends java.lang.Object

This class represents a quadrature formula, given by a list of nodes and weights. The nodes are sorted in ascending order, so lower indices correspond to numerically smaller nodes.

According to general Generator contract, this class is thread-safe.

Author:

Torsten Nahm

Constructor Summary

QuadratureFormula(double[] nodes, double[] weights)
Constructs the quadrature formula from arrays.

QuadratureFormula(java.util.List<java.lang.Double> nodeList, java.util.List<java.lang.Double> weightList)
Constructs the quadrature formula from lists of Doubles.

Method Summary

double	getNode(int index) Returns the node of the specified (node, weight) pair.
double[]	getNodesArray() Returns the nodes as an array.
int	getSize() Returns number of (node, weight) pairs of the formula.
double	getWeight(int index) Returns the weight of the specified (node, weight) pair.
double[]	getWeightsArray() Returns the weights as an array.

Methods inherited from class java.lang.Object

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

Constructor Detail

QuadratureFormula

public QuadratureFormula(double[] nodes,
                         double[] weights)

Constructs the quadrature formula from arrays. The array of nodes must be sorted in ascending order.

Parameters:

nodes - array of nodes

weights - array of weights

Throws:

java.lang.IllegalArgumentException - if the arrays have different lengths

java.lang.IllegalArgumentException - if the nodes are not sorted

QuadratureFormula

public QuadratureFormula(java.util.List<java.lang.Double> nodeList,
                         java.util.List<java.lang.Double> weightList)

Constructs the quadrature formula from lists of Doubles. The list of nodes must be sorted in ascending order.

Parameters:

nodeList - list of nodes

weightList - list of weights

Throws:

java.lang.IllegalArgumentException - if the lists have different lengths

java.lang.IllegalArgumentException - if the nodes are not sorted

Method Detail

getSize

public int getSize()

Returns number of (node, weight) pairs of the formula.

Returns:

number of nodes in the forumla

getNode

public double getNode(int index)

Returns the node of the specified (node, weight) pair.

Parameters:

index - of the pair

Returns:

node with the given index

getWeight

public double getWeight(int index)

Returns the weight of the specified (node, weight) pair.

Parameters:

index - of the pair

Returns:

weight with the given index

getNodesArray

public double[] getNodesArray()

Returns the nodes as an array.

Returns:

nodes array

getWeightsArray

public double[] getWeightsArray()

Returns the weights as an array.

Returns:

weights array