@stdlib/stats
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Standard library statistical functions.
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{{alias}}( x, α, s, m )
Evaluates the logarithm of the probability density function (PDF) for a
Fréchet distribution with shape parameter `α`, scale parameter `s`, and
location `m`.
If provided `NaN` as any argument, the function returns `NaN`.
If provided `α <= 0` or `s <= 0`, the function returns `NaN`.
Parameters
----------
x: number
Input value.
α: number
Shape parameter.
s: number
Scale parameter.
m: number
Location parameter.
Returns
-------
out: number
Evaluated logPDF.
Examples
--------
> var y = {{alias}}( 10.0, 1.0, 3.0, 5.0 )
~-2.72
> y = {{alias}}( -2.0, 1.0, 3.0, -3.0 )
~-1.901
> y = {{alias}}( 0.0, 2.0, 1.0, -1.0 )
~-0.307
> y = {{alias}}( NaN, 0.0, 1.0 )
NaN
> y = {{alias}}( 0.0, NaN, 1.0 )
NaN
> y = {{alias}}( 0.0, 0.0, NaN )
NaN
// Negative scale parameter:
> y = {{alias}}( 0.0, 0.0, -1.0 )
NaN
{{alias}}.factory( α, s, m )
Returns a function for evaluating the logarithm of the probability density
function (PDF) of a Fréchet distribution with shape parameter `α`, scale
parameter `s`, and location `m`.
Parameters
----------
α: number
Shape parameter.
s: number
Scale parameter.
m: number
Location parameter.
Returns
-------
logpdf: Function
Logarithm of probability density function (PDF).
Examples
--------
> var mylogPDF = {{alias}}.factory( 2.0, 3.0, 1.0 );
> var y = mylogPDF( 10.0 )
~-3.812
> y = mylogPDF( 2.0 )
~-6.11
See Also
--------