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+// === Kalman ===
+// Kalman filter for Javascript
+// Copyright (c) 2012 Itamar Weiss
+//
+// Permission is hereby granted, free of charge, to any person obtaining
+// a copy of this software and associated documentation files (the "Software"),
+// to deal in the Software without restriction, including without limitation
+// the rights to use, copy, modify, merge, publish, distribute, sublicense,
+// and/or sell copies of the Software, and to permit persons to whom the
+// Software is furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+// DEALINGS IN THE SOFTWARE.
+
+var Kalman = {
+ version: '0.0.1'
+};
+
+KalmanModel = (function(){
+
+ function KalmanModel(x_0,P_0,F_k,Q_k){
+ this.x_k = x_0;
+ this.P_k = P_0;
+ this.F_k = F_k;
+ this.Q_k = Q_k;
+ }
+
+ KalmanModel.prototype.update = function(o){
+ this.I = Matrix.I(this.P_k.rows());
+ //init
+ this.x_k_ = this.x_k;
+ this.P_k_ = this.P_k;
+
+ //Predict
+ this.x_k_k_ = this.F_k.x(this.x_k_);
+ this.P_k_k_ = this.F_k.x(this.P_k_.x(this.F_k.transpose())).add(this.Q_k);
+
+ //update
+ this.y_k = o.z_k.subtract(o.H_k.x(this.x_k_k_));//observation residual
+ this.S_k = o.H_k.x(this.P_k_k_.x(o.H_k.transpose())).add(o.R_k);//residual covariance
+ this.K_k = this.P_k_k_.x(o.H_k.transpose().x(this.S_k.inverse()));//Optimal Kalman gain
+ this.x_k = this.x_k_k_.add(this.K_k.x(this.y_k));
+ this.P_k = this.I.subtract(this.K_k.x(o.H_k)).x(this.P_k_k_);
+ }
+
+ return KalmanModel;
+})();
+
+KalmanObservation = (function(){
+
+ function KalmanObservation(z_k,H_k,R_k){
+ this.z_k = z_k;//observation
+ this.H_k = H_k;//observation model
+ this.R_k = R_k;//observation noise covariance
+ }
+
+ return KalmanObservation;
+})();