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incrhmean
Compute a harmonic mean incrementally.
The harmonic mean of positive real numbers x_0, x_1, ..., x_{n1}
is defined as
Installation
npm install @stdlib/statsincrhmean
Usage
var incrhmean = require( '@stdlib/statsincrhmean' );
incrhmean()
Returns an accumulator function
which incrementally computes a harmonic mean.
var accumulator = incrhmean();
accumulator( [x] )
If provided an input value x
, the accumulator function returns an updated harmonic mean. If not provided an input value x
, the accumulator function returns the current harmonic mean.
var accumulator = incrhmean();
var v = accumulator( 2.0 );
// returns 2.0
v = accumulator( 1.0 );
// returns ~1.33
v = accumulator( 3.0 );
// returns ~1.64
v = accumulator();
// returns ~1.64
Notes
 Input values are not type checked. If provided
NaN
or a value which, when used in computations, results inNaN
, the accumulated value isNaN
for all future invocations. If nonnumeric 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/randombaserandu' );
var incrhmean = require( '@stdlib/statsincrhmean' );
var accumulator;
var v;
var i;
// Initialize an accumulator:
accumulator = incrhmean();
// For each simulated datum, update the harmonic mean...
for ( i = 0; i < 100; i++ ) {
v = randu() * 100.0;
accumulator( v );
}
console.log( accumulator() );
See Also

@stdlib/statsincr/gmean
: compute a geometric mean incrementally. 
@stdlib/statsincr/mean
: compute an arithmetic mean incrementally. 
@stdlib/statsincr/mhmean
: compute a moving harmonic mean incrementally. 
@stdlib/statsincr/summary
: compute a statistical summary 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 © 20162024. The Stdlib Authors.