@stdlib/stats-incr-mminmax
v0.2.2
Published
Compute a moving minimum and maximum incrementally.
Downloads
153
Readme
incrmminmax
Compute a moving minimum and maximum incrementally.
Installation
npm install @stdlib/stats-incr-mminmax
Usage
var incrmminmax = require( '@stdlib/stats-incr-mminmax' );
incrmminmax( [out,] window )
Returns an accumulator function
which incrementally computes a moving minimum and maximum. The window
parameter defines the number of values over which to compute the moving minimum and maximum.
var accumulator = incrmminmax( 3 );
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 = incrmminmax( new Float64Array( 2 ), 3 );
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 = incrmminmax( 3 );
var mm = accumulator();
// returns null
// Fill the window...
mm = accumulator( 2.0 ); // [2.0]
// returns [ 2.0, 2.0 ]
mm = accumulator( 1.0 ); // [2.0, 1.0]
// returns [ 1.0, 2.0 ]
mm = accumulator( 3.0 ); // [2.0, 1.0, 3.0]
// returns [ 1.0, 3.0 ]
// Window begins sliding...
mm = accumulator( -7.0 ); // [1.0, 3.0, -7.0]
// returns [ -7.0, 3.0 ]
mm = accumulator( -5.0 ); // [3.0, -7.0, -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 minimum and maximum values areNaN
for at leastW-1
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. - As
W
values are needed to fill the window buffer, the firstW-1
returned minimum and maximum values are calculated from smaller sample sizes. Until the window is full, each returned minimum and maximum is calculated from all provided values.
Examples
var randu = require( '@stdlib/random-base-randu' );
var incrmminmax = require( '@stdlib/stats-incr-mminmax' );
var accumulator;
var v;
var i;
// Initialize an accumulator:
accumulator = incrmminmax( 5 );
// For each simulated datum, update the moving minimum and maximum...
for ( i = 0; i < 100; i++ ) {
v = randu() * 100.0;
accumulator( v );
}
console.log( accumulator() );
See Also
@stdlib/stats-incr/max
: compute a maximum value incrementally.@stdlib/stats-incr/min
: compute a minimum value incrementally.@stdlib/stats-incr/mmax
: compute a moving maximum incrementally.@stdlib/stats-incr/minmax
: compute a minimum and maximum incrementally.@stdlib/stats-incr/mmin
: compute a moving minimum incrementally.@stdlib/stats-incr/mrange
: compute a moving range incrementally.
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.
Community
License
See LICENSE.
Copyright
Copyright © 2016-2024. The Stdlib Authors.