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@stdlib/stats

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Standard library statistical functions.

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{{alias}}( x, a, b ) Evaluates the natural logarithm of the cumulative distribution function (CDF) for Kumaraswamy's double bounded distribution with first shape parameter `a` and second shape parameter `b` at a value `x`. If provided `NaN` as any argument, the function returns `NaN`. If `a <= 0` or `b <= 0`, the function returns `NaN`. Parameters ---------- x: number Input value. a: number First shape parameter. b: number Second shape parameter. Returns ------- out: number Evaluated logCDF. Examples -------- > var y = {{alias}}( 0.5, 1.0, 1.0 ) ~-0.693 > y = {{alias}}( 0.5, 2.0, 4.0 ) ~-0.38 > y = {{alias}}( 0.2, 2.0, 2.0 ) ~-2.546 > y = {{alias}}( 0.8, 4.0, 4.0 ) ~-0.13 > y = {{alias}}( -0.5, 4.0, 2.0 ) -Infinity > y = {{alias}}( 1.5, 4.0, 2.0 ) 0.0 > y = {{alias}}( 2.0, -1.0, 0.5 ) NaN > y = {{alias}}( 2.0, 0.5, -1.0 ) NaN > y = {{alias}}( NaN, 1.0, 1.0 ) NaN > y = {{alias}}( 0.0, NaN, 1.0 ) NaN > y = {{alias}}( 0.0, 1.0, NaN ) NaN {{alias}}.factory( a, b ) Returns a function for evaluating the natural logarithm of the cumulative distribution function (CDF) of a Kumaraswamy's double bounded distribution with first shape parameter `a` and second shape parameter `b`. Parameters ---------- a: number First shape parameter. b: number Second shape parameter. Returns ------- logcdf: Function Logarithm of cumulative distribution function (CDF). Examples -------- > var mylogcdf = {{alias}}.factory( 0.5, 1.0 ); > var y = mylogcdf( 0.8 ) ~-0.112 > y = mylogcdf( 0.3 ) ~-0.602 See Also --------