@stdlib/stats
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Standard library statistical functions.
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{{alias}}( x, a, b, c )
Evaluates the natural logarithm of the probability density function (PDF)
for a triangular distribution with minimum support `a`, maximum support `b`,
and mode `c` at a value `x`.
If the condition `a <= c <= b` is not satisfied, the function returns `NaN`.
If either `a`, `b`, or `c` is `NaN`, the function returns `NaN`.
Parameters
----------
x: number
Input value.
a: number
Minimum support.
b: number
Maximum support.
c: number
Mode.
Returns
-------
out: number
Evaluated logPDF.
Examples
--------
> var y = {{alias}}( 0.5, -1.0, 1.0, 0.0 )
~-0.693
> y = {{alias}}( 0.5, -1.0, 1.0, 0.5 )
0.0
> y = {{alias}}( -10.0, -20.0, 0.0, -2.0 )
~-2.89
> y = {{alias}}( -2.0, -1.0, 1.0, 0.0 )
-Infinity
> y = {{alias}}( NaN, 0.0, 1.0, 0.5 )
NaN
> y = {{alias}}( 0.0, NaN, 1.0, 0.5 )
NaN
> y = {{alias}}( 0.0, 0.0, NaN, 0.5 )
NaN
> y = {{alias}}( 2.0, 1.0, 0.0, NaN )
NaN
> y = {{alias}}( 2.0, 1.0, 0.0, 1.5 )
NaN
{{alias}}.factory( a, b, c )
Returns a function for evaluating the natural logarithm of the probability
density function (PDF) of a triangular distribution with minimum support
`a`, maximum support `b`, and mode `c`.
Parameters
----------
a: number
Minimum support.
b: number
Maximum support.
c: number
Mode.
Returns
-------
logpdf: Function
Logarithm of probability density function (PDF).
Examples
--------
> var mylogpdf = {{alias}}.factory( 0.0, 10.0, 5.0 );
> var y = mylogpdf( 2.0 )
~-2.526
> y = mylogpdf( 12.0 )
-Infinity
See Also
--------