ekf: remove unused function

EKF/ekf.h

@@ -545,9 +545,6 @@ private:
 	// jacobian : 4x1 vector of partial derivatives of observation wrt each quaternion state
 	void updateQuaternion(const float innovation, const float variance, const float gate_sigma, const float (&yaw_jacobian)[4]);
 
-	// shrinks the yaw axis uncertainty of quaternion covariances by fusing a zero innovation yaw observation
-	void shrinkYawVariance();
-
 	// fuse the yaw angle obtained from a dual antenna GPS unit
 	void fuseGpsAntYaw();
 

EKF/ekf_helper.cpp

@@ -1800,18 +1800,3 @@ void Ekf::runYawEKFGSF()
 		yawEstimator.setVelocity(_gps_sample_delayed.vel.xy(), _gps_sample_delayed.vacc);
 	}
 }
-
-void Ekf::shrinkYawVariance()
-{
-	if (fabsf(_R_to_earth(2, 0)) < fabsf(_R_to_earth(2, 1))) {
-		// rolled more than pitched so use 321 rotation order to define yaw angle
-		// and fuse a zero innovation yaw to shrink quaternion yaw variance
-		fuseYaw321(0.0f, 0.25f, true);
-
-	} else {
-		// pitched more than rolled so use 312 rotation order to define yaw angle
-		// and fuse a zero innovation yaw to shrink quaternion yaw variance
-		fuseYaw312(0.0f, 0.25f, true);
-
-	}
-}