@stdlib/stats
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Standard library statistical functions.
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{{alias}}( x, α, β )
Evaluates the natural logarithm of the probability density function (PDF)
for a beta prime distribution with first shape parameter `α` and second
shape parameter `β` at a value `x`.
If provided `NaN` as any argument, the function returns `NaN`.
If `α <= 0` or `β <= 0`, the function returns `NaN`.
Parameters
----------
x: number
Input value.
α: number
First shape parameter.
β: number
Second shape parameter.
Returns
-------
out: number
Natural logarithm of the PDF.
Examples
--------
> var y = {{alias}}( 0.5, 1.0, 1.0 )
~-0.811
> y = {{alias}}( 0.5, 2.0, 4.0 )
~-0.13
> y = {{alias}}( 0.2, 2.0, 2.0 )
~-0.547
> y = {{alias}}( 0.8, 4.0, 4.0 )
~-0.43
> y = {{alias}}( -0.5, 4.0, 2.0 )
-Infinity
> y = {{alias}}( 0.5, -1.0, 0.5 )
NaN
> y = {{alias}}( 0.5, 0.5, -1.0 )
NaN
> y = {{alias}}( NaN, 1.0, 1.0 )
NaN
> y = {{alias}}( 0.5, NaN, 1.0 )
NaN
> y = {{alias}}( 0.5, 1.0, NaN )
NaN
{{alias}}.factory( α, β )
Returns a function for evaluating the natural logarithm of the probability
density function (PDF) of a beta prime distribution with first shape
parameter `α` and second shape parameter `β`.
Parameters
----------
α: number
First shape parameter.
β: number
Second shape parameter.
Returns
-------
fcn: Function
Function to evaluate the natural logarithm of the PDF.
Examples
--------
> var mylogpdf = {{alias}}.factory( 0.5, 0.5 );
> var y = mylogpdf( 0.8 )
~-1.62
> y = mylogpdf( 0.3 )
~-0.805
See Also
--------