MATLAB: How to extract coefficient of difference equation in Matlab

differential equations

I have a difference equation below:

Y(t) = 6*x*(t)+4*x*(t-1)-6*x*(t-3)+2*Y*(t-1)

How to extract coefficient of difference equation

To extract coefficient of difference equation, a possible workaround would be as follows -

Convert difference equation into a f(z) using Z transforms. Documentation available here
Extract thne coefficients of f(z) using sym2poly. Solution can be found here

If I remember correctly, diff works across the first non-singleton dimension. So diff(A) works across columns and diff(A(1, :)) works across rows.

x = [1,2,3; 4,5,6];
diff(x, [], 1)
ans =
   3     3     3
diff(x, [], 2)
ans =
   1     1
   1     1

wrcoef() gives the orthogonal projection of the signal onto the vector subspace (approximation or wavelet) at the given level.

If you want to get the approximation coefficients from the GUI then you can do:

Export to Workspace -> Export Coefficients

Assume the variable in the workspace is my_VAR_1, then

   appcoeff = my_VAR_1.coefs(1:my_VAR_1.longs(1));

are the approximation coefficients at the level of the GUI decomposition.