incrnansumabs2

Compute a sum of squared absolute values incrementally, ignoring NaN values.

The sum of squared absolute values is defined as

Usage

var incrnansumabs2 = require( '@stdlib/stats/incr/nansumabs2' );

incrnansumabs2()

Returns an accumulator function which incrementally computes a sum of squared absolute values, ignoring NaN values.

var accumulator = incrnansumabs2();

accumulator( [x] )

If provided an input value x, the accumulator function returns an updated sum. If not provided an input value x, the accumulator function returns the current sum.

var accumulator = incrnansumabs2();

var sum = accumulator( 2.0 );
// returns 4.0

sum = accumulator( -1.0 );
// returns 5.0

sum = accumulator( NaN );
// returns 5.0

sum = accumulator( -3.0 );
// returns 14.0

sum = accumulator();
// returns 14.0

Notes

Input values are not type checked. If non-numeric inputs are possible, you are advised to type check and handle accordingly before passing the value to the accumulator function.
For long running accumulations or accumulations of large numbers, care should be taken to prevent overflow.

Examples

var randu = require( '@stdlib/random/base/randu' );
var incrnansumabs2 = require( '@stdlib/stats/incr/nansumabs2' );

var accumulator;
var v;
var i;

// Initialize an accumulator:
accumulator = incrnansumabs2();

// For each simulated datum, update the sum...
for ( i = 0; i < 100; i++ ) {
    v = ( randu()*100.0 ) - 50.0;
    accumulator( v );
}
console.log( accumulator() );