You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: ExINS_Euler.m
    path of file: ./repos/MSS/mssExamples
    
    the code of the file until where you have to start completion: % ExINS_Euler - Error-state (indirect) feedback Kalman filter f
    
function ins_euler when there are no new GNSS 
% measurements.
%
% Author:    Thor I. Fossen
% Date:      14 Jan 2021 
% Revisions: 27 Jan 2021, minor updates of the documentation

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% USER INPUTS
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
f_s    = 100;     % sampling frequency [Hz]
f_gnss = 1;       % GNSS measurement frequency [Hz]

% Flags
vel = 1;          % 0 = no velocity measurement, 1 = velocity aiding

% Parameters
Z = f_s/f_gnss;   % ratio betwween sampling/IMU frequencies
h  = 1/f_s; 	  % sampling time: h  = 1/f_s (s) 
h_gnss = 1/f_gnss;  

% simulation parameters
N  = 10000;		  % no. of iterations
b_acc = [0.1 0.3 -0.1]';
b_ars = [0.05 0.1 -0.05]';
   
% initial values for x for signal generator
x = [zeros(1,6) b_acc' zeros(1,3) b_ars']';	        

% initialization of Kalman filter
P_prd = eye(15);

% process noise weights: vel, acc_bias, w_nb, ars_bias
Qd = diag([0.1 0.1 0.1  0.001 0.001 0.001  0.1 0.1 0.1  0.001 0.001 0.001]);
   
if (vel == 0 )  % position and compass aiding 
     
   Rd = diag([0.1 0.1 0.1  1 1 1  0.1]);  % pos, acc, compass

else % position/velocity aiding + compass 
      
   Rd = diag([1 1 1  1 1 1  1 1 1  0.1]);  % pos, vel, acc, psi

end