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ERFCX Complimentary Weighted Error Function

Usage

Computes the complimentary error function for real arguments. The erfcx function takes only a single argument

  y = erfcx(x)

where x is either a float or double array. The output vector y is the same size (and type) as x.

Function Internals

The erfcx function is defined by the integral:

$\displaystyle \mathrm{erfcx}(x) = \frac{2e^{x^2}}{\sqrt{\pi}}\int_{x}^{\infty} e^{-t^2}   dt,
$

and is an exponentially weighted integral of the normal distribution.

Example

Here is a plot of the erfcx function over the range [-5,5].

--> x = linspace(0,5);
--> y = erfcx(x);
--> plot(x,y); xlabel('x'); ylabel('erfcx(x)');

which results in the following plot.

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Samit K. Basu 2005-03-16