@stdlib/stats-incr-minmax NPM

incrminmax

Compute a minimum and maximum incrementally.

Installation

npm install @stdlib/stats-incr-minmax

Usage

var incrminmax = require( '@stdlib/stats-incr-minmax' );

incrminmax( [out] )

Returns an accumulator function which incrementally computes a minimum and maximum.

var accumulator = incrminmax();

By default, the returned accumulator function returns the minimum and maximum as a two-element array. To avoid unnecessary memory allocation, the function supports providing an output (destination) object.

var Float64Array = require( '@stdlib/array-float64' );

var accumulator = incrminmax( new Float64Array( 2 ) );

accumulator( [x] )

If provided an input value x, the accumulator function returns updated minimum and maximum values. If not provided an input value x, the accumulator function returns the current minimum and maximum values.

var accumulator = incrminmax();

var mm = accumulator();
// returns null

mm = accumulator( 2.0 );
// returns [ 2.0, 2.0 ]

mm = accumulator( 1.0 );
// returns [ 1.0, 2.0 ]

mm = accumulator( 3.0 );
// returns [ 1.0, 3.0 ]

mm = accumulator( -7.0 );
// returns [ -7.0, 3.0 ]

mm = accumulator( -5.0 );
// returns [ -7.0, 3.0 ]

mm = accumulator();
// returns [ -7.0, 3.0 ]

Notes

Input values are not type checked. If provided NaN, the accumulated values are equal to NaN for all future invocations. If non-numeric inputs are possible, you are advised to type check and handle accordingly before passing the value to the accumulator function.

Examples

var randu = require( '@stdlib/random-base-randu' );
var incrminmax = require( '@stdlib/stats-incr-minmax' );

var accumulator;
var v;
var i;

// Initialize an accumulator:
accumulator = incrminmax();

// For each simulated datum, update the minimum and maximum...
for ( i = 0; i < 100; i++ ) {
    v = randu() * 100.0;
    accumulator( v );
}
console.log( accumulator() );

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.