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Cumulative Distribution Function
Gumbel distribution cumulative distribution function.
The cumulative distribution function for a Gumbel random variable is
where mu is the location parameter and beta > 0 is the scale parameter.
Usage
var cdf = require( '@stdlib/stats/base/dists/gumbel/cdf' );
cdf( x, mu, beta )
Evaluates the cumulative distribution function (CDF) for a Gumbel distribution with parameters mu (location parameter) and beta (scale parameter).
var y = cdf( 10.0, 0.0, 3.0 );
// returns ~0.965
y = cdf( -2.0, 0.0, 3.0 );
// returns ~0.143
y = cdf( 0.0, 0.0, 1.0 );
// returns ~0.368
If provided NaN as any argument, the function returns NaN.
var y = cdf( NaN, 0.0, 1.0 );
// returns NaN
y = cdf( 0.0, NaN, 1.0 );
// returns NaN
y = cdf( 0.0, 0.0, NaN );
// returns NaN
If provided beta <= 0, the function returns NaN.
var y = cdf( 2.0, 0.0, -1.0 );
// returns NaN
y = cdf( 2.0, 0.0, 0.0 );
// returns NaN
cdf.factory( mu, beta )
Returns a function for evaluating the cumulative distribution function of a Gumbel distribution with parameters mu (location parameter) and beta (scale parameter).
var mycdf = cdf.factory( 0.0, 3.0 );
var y = mycdf( 10.0 );
// returns ~0.965
y = mycdf( -2.0 );
// returns ~0.143
Examples
var randu = require( '@stdlib/random/base/randu' );
var cdf = require( '@stdlib/stats/base/dists/gumbel/cdf' );
var beta;
var mu;
var x;
var y;
var i;
for ( i = 0; i < 100; i++ ) {
x = randu() * 10.0;
mu = randu() * 10.0;
beta = randu() * 10.0;
y = cdf( x, mu, beta );
console.log( 'x: %d, µ: %d, β: %d, F(x;µ,β): %d', x.toFixed( 4 ), mu.toFixed( 4 ), beta.toFixed( 4 ), y.toFixed( 4 ) );
}