Compute an arithmetic mean incrementally.
The arithmetic mean is defined as
var incrmean = require( '@stdlib/stats/incr/mean' );Returns an accumulator function which incrementally computes an arithmetic mean.
var accumulator = incrmean();If provided an input value x, the accumulator function returns an updated mean. If not provided an input value x, the accumulator function returns the current mean.
var accumulator = incrmean();
var mu = accumulator( 2.0 );
// returns 2.0
mu = accumulator( 1.0 );
// returns 1.5
mu = accumulator( 3.0 );
// returns 2.0
mu = accumulator();
// returns 2.0- Input values are not type checked. If provided
NaNor a value which, when used in computations, results inNaN, the accumulated value isNaNfor 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.
var randu = require( '@stdlib/random/base/randu' );
var incrmean = require( '@stdlib/stats/incr/mean' );
var accumulator;
var v;
var i;
// Initialize an accumulator:
accumulator = incrmean();
// For each simulated datum, update the mean...
for ( i = 0; i < 100; i++ ) {
v = randu() * 100.0;
accumulator( v );
}
console.log( accumulator() );@stdlib/stats/incr/midrange: compute a mid-range incrementally.@stdlib/stats/incr/mmean: compute a moving arithmetic mean incrementally.@stdlib/stats/incr/stdev: compute a corrected sample standard deviation incrementally.@stdlib/stats/incr/sum: compute a sum incrementally.@stdlib/stats/incr/summary: compute a statistical summary incrementally.@stdlib/stats/incr/variance: compute an unbiased sample variance incrementally.