@stdlib/stats
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Standard library statistical functions.
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{{alias}}( t, k, λ )
Evaluates the moment-generating function (MGF) for an Erlang distribution
with shape parameter `k` and rate parameter `λ` at a value `t`.
If provided `NaN` as any argument, the function returns `NaN`.
If not provided a nonnegative integer for `k`, the function returns `NaN`.
If provided a non-positive value for `λ`, the function returns `NaN`.
Parameters
----------
t: number
Input value.
k: number
Shape parameter.
λ: number
Rate parameter.
Returns
-------
out: number
Evaluated MGF.
Examples
--------
> var y = {{alias}}( 0.3, 1, 1.0 )
~1.429
> y = {{alias}}( 2.0, 2, 3.0 )
~9.0
> y = {{alias}}( -1.0, 2, 2.0 )
~0.444
> y = {{alias}}( NaN, 1, 1.0 )
NaN
> y = {{alias}}( 0.0, NaN, 1.0 )
NaN
> y = {{alias}}( 0.0, 1, NaN )
NaN
> y = {{alias}}( 0.2, -2, 0.5 )
NaN
> y = {{alias}}( 0.2, 0.5, 0.5 )
NaN
> y = {{alias}}( 0.2, 1, 0.0 )
NaN
> y = {{alias}}( 0.2, 1, -5.0 )
NaN
{{alias}}.factory( k, λ )
Returns a function for evaluating the moment-generating function (MGF) of an
Erlang distribution with shape parameter `k` and rate parameter `λ`.
Parameters
----------
k: number
Shape parameter.
λ: number
Rate parameter.
Returns
-------
mgf: Function
Moment-generating function (MGF).
Examples
--------
> var myMGF = {{alias}}.factory( 2, 0.5 );
> var y = myMGF( 0.2 )
~2.778
> y = myMGF( -0.5 )
0.25
See Also
--------