Median

Geometric distribution median.

The median for a geometric random variable is

upper M e d i a n left-parenthesis upper X right-parenthesis equals left ceiling StartFraction negative 1 Over log Subscript 2 Baseline left-parenthesis 1 minus p right-parenthesis EndFraction right ceiling minus 1

where p is the success probability.

Usage

var median = require( '@stdlib/math/base/dists/geometric/median' );

median( p )

Returns the median of a geometric distribution with success probability p.

var v = median( 0.1 );
// returns 6

v = median( 0.5 );
// returns 0

If provided a success probability p outside of [0,1], the function returns NaN.

var v = median( NaN );
// returns NaN

v = median( 1.5 );
// returns NaN

v = median( -1.0 );
// returns NaN

Examples

var randu = require( '@stdlib/random/base/randu' );
var round = require( '@stdlib/math/base/special/round' );
var median = require( '@stdlib/math/base/dists/geometric/median' );

var v;
var i;
var p;

for ( i = 0; i < 10; i++ ) {
    p = randu();
    v = median( p );
    console.log( 'p: %d, Median(X;p): %d', p.toFixed( 4 ), v.toFixed( 4 ) );
}