diff --git a/kalman1d_eval.m b/kalman1d_eval.m
index cff333c..f5ab707 100644
--- a/kalman1d_eval.m
+++ b/kalman1d_eval.m
@@ -103,13 +103,13 @@ else
 		% -----------------------
 		%y = sin(2*pi*i/200)
 		%ys = cos(2*pi*i/200)
-		ys = (Y(1) - y)/dt;
+		dy = dy + 0.00;
 		y = y + dy;
-		dy = dy + 0.0
+		ys = (y - Y(1))/dt;
 		% -----------------------
 
 		Z = variance*randn(size(Z))/sqrt(12);
-		Y = C*[y ys]' + Z;
+		Y = C*[y ys]'  + Z;
 		
 		% Update process matrix P and state matrix X
 		I = eye(length(K));