% stategen_init.m:  generates matrices A,B,C,D for continuous
% state space model.
clear;

n=input('Enter number of states (n): ');
m=input('Enter number of inputs (m): ');
r=input('Enter number of outputs (r): ');

disp('Enter coefficients for differential equation.');
disp('The negatives of these will become the bottom ');
disp('row of the companion matrix A:');
A = zeros(n);
for i=0:n-1
  if i<n-1
      A(i+1,i+2) = 1;
  end
  A(n,n-i) = input(['a(',num2str(i+1),')=']);
  A(n,n-i) = -A(n,n-i);
end
disp('Enter elements for B matrix (n x m):');
B = zeros(n,m);
for i=1:n
    for j=1:m
        B(i,j) = input(['B(',num2str(i),',',num2str(j),')=']);
    end
end

disp('Enter elements for C matrix (r x n):');
C = zeros(r,n);
for i=1:r
    for j=1:n
        C(i,j) = input(['C(',num2str(i),',',num2str(j),')=']);
    end
end

disp('Enter elements for D matrix (r x m):');
D = zeros(r,m);
for i=1:r
    for j=1:m
        D(i,j) = input(['D(',num2str(i),',',num2str(j),')=']);
    end
end

% Generate matrix to map scalar input into first
% element of control input u.
% Change any elements after this scdript completes
% to drive other inputs.
E = zeros(m,1);
E(1,1)=1;

disp('Note: You can change any of the matrices');
disp('manually by using the Array Editor after ');
disp('you run this script.  Then, open and execute');
disp('the model stategen.mdl in Simulink.');
disp(' ');
disp('Also, after tweaking the matrices in the Workspace');
disp('and playing with the simulation, you can save the');
disp('Workspace in a .mat file for easy loading later.');