function incrsumabs2() {
	var sum = 0.0;
	var FLG;
	return accumulator;

	/**
	* If provided a value, the accumulator function returns an updated sum. If not provided a value, the accumulator function returns the current sum.
	*
	* @private
	* @param {number} [x] - new value
	* @returns {(number|null)} sum or null
	*/
	function accumulator( x ) {
		if ( arguments.length === 0 ) {
			return ( FLG ) ? sum : null;
		}
		FLG = true;
		sum += x * x;
		return sum;
	}
}
Returns an accumulator function which incrementally computes a sum of squared absolute values.

@returns {Function} accumulator function

@example
var accumulator = incrsumabs2();

var sum = accumulator();
// returns null

sum = accumulator( 2.0 );
// returns 4.0

sum = accumulator( -5.0 );
// returns 29.0

sum = accumulator();
// returns 29.0