Kernel Betaincinv

Inverse of the lower incomplete beta function.

Installation

npm install @stdlib/math-base-special-kernel-betaincinv

Usage

var kernelBetaincinv = require( '@stdlib/math-base-special-kernel-betaincinv' );

kernelBetaincinv( a, b, p, q )

Inverts the lower regularized incomplete beta function at a > 0 and b > 0. Input probabilities p and q must satisfy p = 1 - q. The function returns a two-element array holding the function value y and 1-y.

var y = kernelBetaincinv( 3.0, 3.0, 0.2, 0.8 );
// returns [ ~0.327, ~0.673 ]

y = kernelBetaincinv( 3.0, 3.0, 0.4, 0.6 );
// returns [ ~0.446, ~0.554 ]

y = kernelBetaincinv( 1.0, 6.0, 0.4, 0.6 );
// returns [ ~0.082, ~0.918 ]

y = kernelBetaincinv( 1.0, 6.0, 0.8, 0.2 );
// returns [ ~0.235, ~0.765 ]

Examples

var randu = require( '@stdlib/random-base-randu' );
var kernelBetaincinv = require( '@stdlib/math-base-special-kernel-betaincinv' );

var i;
var p;
var a;
var b;

for ( i = 0; i < 100; i++ ) {
    p = randu();
    a = randu() * 10.0;
    b = randu() * 10.0;
    console.log( 'p: %d, \t a: %d, \t b: %d, \t f(p,a,b): %d', p.toFixed( 4 ), a.toFixed( 4 ), b.toFixed( 4 ), kernelBetaincinv( a, b, p, 1.0-p )[ 0 ] );
}

See Also

• @stdlib/math-base/special/betaincinv: inverse incomplete beta function.

Notice

This package is part of stdlib, a standard library for JavaScript and Node.js, with an emphasis on numerical and scientific computing. The library provides a collection of robust, high performance libraries for mathematics, statistics, streams, utilities, and more.

For more information on the project, filing bug reports and feature requests, and guidance on how to develop stdlib, see the main project repository.

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Copyright

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