@stdlib/stats
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Standard library statistical functions.
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{{alias}}( x, α, β )
Evaluates the cumulative distribution function (CDF) for an inverse gamma
distribution with shape parameter `α` and scale parameter `β` at a value
`x`.
If `α <= 0` or `β <= 0`, the function returns `NaN`.
If provided `NaN` as any argument, the function returns `NaN`.
Parameters
----------
x: number
Input value.
α: number
Shape parameter.
β: number
Scale parameter.
Returns
-------
out: number
Evaluated CDF.
Examples
--------
> var y = {{alias}}( 2.0, 1.0, 1.0 )
~0.607
> y = {{alias}}( 2.0, 3.0, 1.0 )
~0.986
> y = {{alias}}( -1.0, 2.0, 2.0 )
0.0
> y = {{alias}}( {{alias:/constants/float64/pinf}}, 4.0, 2.0 )
1.0
> y = {{alias}}( {{alias:/constants/float64/ninf}}, 4.0, 2.0 )
0.0
> y = {{alias}}( NaN, 0.0, 1.0 )
NaN
> y = {{alias}}( 0.0, NaN, 1.0 )
NaN
> y = {{alias}}( 0.0, 0.0, NaN )
NaN
> y = {{alias}}( 2.0, -1.0, 1.0 )
NaN
> y = {{alias}}( 2.0, 1.0, -1.0 )
NaN
{{alias}}.factory( α, β )
Returns a function for evaluating the cumulative distribution function (CDF)
of an inverse gamma distribution with shape parameter `α` and scale
parameter `β`.
Parameters
----------
α: number
Shape parameter.
β: number
Scale parameter.
Returns
-------
cdf: Function
Cumulative distribution function (CDF).
Examples
--------
> var myCDF = {{alias}}.factory( 2.0, 0.5 );
> var y = myCDF( 0.5 )
~0.736
> y = myCDF( 2.0 )
~0.974
See Also
--------