org.lsmp.djep.xjep.function
Class Simpson

java.lang.Object
  org.nfunk.jep.function.PostfixMathCommand
      org.lsmp.djep.xjep.function.SumType
          org.lsmp.djep.xjep.function.Trapezium
              org.lsmp.djep.xjep.function.Simpson

All Implemented Interfaces:

CallbackEvaluationI, PostfixMathCommandI

public class Simpson
extends Trapezium

The Simpson rule for approximation to a definite integral. h * (y0 + yn + 4(y1+y3+...+y_(n-1)) + 2(y2+y4+...+y_(n-2)) ) /3 where h = (xn-x0)/n, yi = f(xi) Simpson(x^2,x,0,10,0.5) finds an approximation for int(x^2) where x runs from 0 to 10 in steps of h=0.5.

Author:

Rich Morris Created on 10-Sept-2004

Field Summary

Fields inherited from class org.lsmp.djep.xjep.function.SumType

name

Fields inherited from class org.nfunk.jep.function.PostfixMathCommand

curNumberOfParameters, numberOfParameters

Constructor Summary

Simpson()

Method Summary

java.lang.Object

evaluate(java.lang.Object[] elements) Evaluates the function given the set of y values.

Methods inherited from class org.lsmp.djep.xjep.function.Trapezium

evaluate

Methods inherited from class org.lsmp.djep.xjep.function.SumType

checkNumberOfParameters, evaluate, run

Methods inherited from class org.nfunk.jep.function.PostfixMathCommand

checkStack, getNumberOfParameters, setCurNumberOfParameters

Methods inherited from class java.lang.Object

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

Constructor Detail

Simpson

public Simpson()

Method Detail

evaluate

public java.lang.Object evaluate(java.lang.Object[] elements)
                          throws ParseException

Description copied from class: SumType

Evaluates the function given the set of y values. For example for Sum(x^2,x,1,5) the function will be passed the array [1,4,9,16,25].

Overrides:

evaluate in class Trapezium

Parameters:

elements - the y values

Returns:

the result of the function

Throws:

ParseException