The Error Function.

Contents

Interface Function Documentation Page Comments

Interface

#include <codecogs/maths/special/errorfn.h>

using namespace Maths::Special;

	double	errorFn (double x) The Error Function.
	Real	cc_specialErrorFn (Real x) This function is available as a Microsoft Excel add-in.

Function Documentation

The Error Functionis defined by equation and has the shape

Warnings:

This approximation of erf is only valid between -3 and 3

References:

• Eric W. Weisstein. "Erf." From MathWorld--A Wolfram Web Resource
• http://mathworld.wolfram.com/Erf.html

Example:

#include <codecogs/maths/special/errorfn.h>
#include <stdio.h>
using namespace Maths::Special;
int main(  )
{
  double x = 0.5;
  printf("\n errorFn(%f) = %f", x, errorFn(x));
  return getchar();
}

Output:

errorFn(0.500000) = 0.520500

Parameters:

x	the upper limit of the integral (-3<x<3)

Returns:

the value of the Error Function evaluated at the given abscissa

Authors:

Vince Cole (March 2005)