@stdlib/stats
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Standard library statistical functions.
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{{alias}}( x, k )
Evaluates the cumulative distribution function (CDF) for a chi distribution
with degrees of freedom `k` at a value `x`.
If provided `NaN` as any argument, the function returns `NaN`.
If provided `k < 0`, the function returns `NaN`.
Parameters
----------
x: number
Input value.
k: number
Degrees of freedom.
Returns
-------
out: number
Evaluated CDF.
Examples
--------
> var y = {{alias}}( 2.0, 3.0 )
~0.739
> y = {{alias}}( 1.0, 0.5 )
~0.846
> y = {{alias}}( -1.0, 4.0 )
0.0
> y = {{alias}}( NaN, 1.0 )
NaN
> y = {{alias}}( 0.0, NaN )
NaN
// Negative degrees of freedom:
> y = {{alias}}( 2.0, -1.0 )
NaN
// Degenerate distribution when `k = 0`:
> y = {{alias}}( 2.0, 0.0 )
1.0
> y = {{alias}}( -2.0, 0.0 )
0.0
> y = {{alias}}( 0.0, 0.0 )
0.0
{{alias}}.factory( k )
Returns a function for evaluating the cumulative distribution function (CDF)
of a chi distribution with degrees of freedom `k`.
Parameters
----------
k: number
Degrees of freedom.
Returns
-------
cdf: Function
Cumulative distribution function (CDF).
Examples
--------
> var mycdf = {{alias}}.factory( 1.0 );
> var y = mycdf( 2.0 )
~0.954
> y = mycdf( 1.2 )
~0.77
See Also
--------