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@stdlib/stats

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Standard library statistical functions.

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{{alias}}( x, n, p ) Evaluates the probability mass function (PMF) for a binomial distribution with number of trials `n` and success probability `p` at a value `x`. If provided `NaN` as any argument, the function returns `NaN`. If provided a number of trials `n` which is not a nonnegative integer, the function returns `NaN`. If `p < 0` or `p > 1`, the function returns `NaN`. Parameters ---------- x: number Input value. n: integer Number of trials. p: number Success probability. Returns ------- out: number Evaluated PMF. Examples -------- > var y = {{alias}}( 3.0, 20, 0.2 ) ~0.205 > y = {{alias}}( 21.0, 20, 0.2 ) 0.0 > y = {{alias}}( 5.0, 10, 0.4 ) ~0.201 > y = {{alias}}( 0.0, 10, 0.4 ) ~0.006 > y = {{alias}}( NaN, 20, 0.5 ) NaN > y = {{alias}}( 0.0, NaN, 0.5 ) NaN > y = {{alias}}( 0.0, 20, NaN ) NaN > y = {{alias}}( 2.0, 1.5, 0.5 ) NaN > y = {{alias}}( 2.0, -2.0, 0.5 ) NaN > y = {{alias}}( 2.0, 20, -1.0 ) NaN > y = {{alias}}( 2.0, 20, 1.5 ) NaN {{alias}}.factory( n, p ) Returns a function for evaluating the probability mass function (PMF) of a binomial distribution with number of trials `n` and success probability `p`. Parameters ---------- n: integer Number of trials. p: number Success probability. Returns ------- pmf: Function Probability mass function (PMF). Examples -------- > var mypmf = {{alias}}.factory( 10, 0.5 ); > var y = mypmf( 3.0 ) ~0.117 > y = mypmf( 5.0 ) ~0.246 See Also --------