@barchart/common-js/lang/math.js

Library of common JavaScript utilities

import * as is from './is.js';

/**
 * Indicates whether two numbers are approximately equal within floating-point precision.
 *
 * @public
 * @param {*} a
 * @param {*} b
 * @returns {boolean}
 */
export function approximate(a, b) {
	if (!is.number(a) || !is.number(b)) {
		return false;
	}

	if (a === b) {
		return true;
	}

	if (isFinite(a) && isFinite(b)) {
		const absoluteDifference = Math.abs(a - b);

		if (absoluteDifference < Number.EPSILON) {
			return true;
		} else {
			return !(absoluteDifference > Math.max(Math.abs(a), Math.abs(b)) * Number.EPSILON);
		}
	} else {
		return false;
	}
}