do not use es2015 here

third-party/kalman.js

@@ -11,8 +11,7 @@
 
 
 
-class KalmanFilter {
-
+function KalmanFilter(params) {
 	/**
 	* Create 1-dimensional kalman filter
 	* @param  {Number} options.R Process noise
@@ -22,14 +21,13 @@ class KalmanFilter {
 	* @param  {Number} options.C Measurement vector
 	* @return {KalmanFilter}
 	*/
-  constructor({R = 1, Q = 1, A = 1, B = 0, C = 1} = {}) {
 
-    this.R = R; // noise power desirable
-    this.Q = Q; // noise power estimated
+	this.R = typeof params.R == "undefined" ? 1 : params.R; // noise power desirable
+	this.Q = typeof params.Q == "undefined" ? 1 : params.Q; // noise power estimated
 
-    this.A = A;
-    this.C = C;
-    this.B = B;
+	this.A = typeof params.A == "undefined" ? 1 : params.A;
+	this.C = typeof params.C == "undefined" ? 1 : params.C;
+	this.B = typeof params.B == "undefined" ? 0 : params.B;
 	this.cov = NaN;
 	this.x = NaN; // estimated signal without noise
 }
@@ -40,8 +38,9 @@ class KalmanFilter {
 * @param  {Number} u Control
 * @return {Number}
 */
-  filter(z, u = 0) {
-
+KalmanFilter.prototype.filter = function (z, u) {
+	if (typeof u == "undefined")
+		u = 0;
 	if (isNaN(this.x)) {
 		this.x = (1 / this.C) * z;
 		this.cov = (1 / this.C) * this.Q * (1 / this.C);
@@ -67,7 +66,7 @@ class KalmanFilter {
 * Return the last filtered measurement
 * @return {Number}
 */
-  lastMeasurement() {
+KalmanFilter.prototype.lastMeasurement = function () {
 	return this.x;
 }
 
@@ -75,7 +74,7 @@ class KalmanFilter {
 * Set measurement noise Q
 * @param {Number} noise
 */
-  setMeasurementNoise(noise) {
+KalmanFilter.prototype.setMeasurementNoise = function (noise) {
 	this.Q = noise;
 }
 
@@ -83,7 +82,7 @@ class KalmanFilter {
 * Set the process noise R
 * @param {Number} noise
 */
-  setProcessNoise(noise) {
+KalmanFilter.prototype.setProcessNoise = function (noise) {
 	this.R = noise;
 }
-}
+