Package org.apache.commons.numbers.gamma
Class Erf
- java.lang.Object
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- org.apache.commons.numbers.gamma.Erf
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public final class Erf extends Object
Error function.\[ \operatorname{erf}(z) = \frac{2}{\sqrt\pi}\int_0^z e^{-t^2}\,dt \]
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Method Detail
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value
public static double value(double x)
Returns the error function.The returned value is always between -1 and 1 (inclusive). The appropriate extreme is returned when
erf(x)
is indistinguishable from either -1 or 1 atdouble
precision.Special cases:
- If the argument is 0, then the result is 0.
- If the argument is
> 6
, then the result is 1. - If the argument is
< 6
, then the result is -1. - If the argument is nan, then the result is nan.
- Parameters:
x
- the value.- Returns:
- the error function.
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