Matrix formulation with matrix multiplication and raising to N-power

Hey guys,

I'm currently working on designing an MPC controller manually and for some reason I get an error defining a Matrix of 8x7 dimension such as :

B = [0.005;

0.1] and B_tilda corresponding to the new states with a prediction Horizon of N = 7 is in the screenschot attached. I keep getting this error :

I would really appreciate any help.

[Torsten]

You forgot to include your code.

[wissal zaher]

% B_tilda = [0,B,A*B,A.^2*B,A.^3*B,A.^4*B,A.^5*B,A.^6*B;

% 0,0,B,A*B,A.^2*B,A.^3*B,A.^4*B,A.^5*B;

% 0,0,0,B,A*B,A.^2*B,A.^3*B,A.^4*B;

% 0,0,0,0,B,A*B,A.^2*B,A.^3*B;

% 0,0,0,0,0,B,A*B,A.^2*B;

% 0,0,0,0,0,0,B,A*B;

% 0,0,0,0,0,0,0,B]'

Answer 1

[Steven Lord]

If your B is in fact a 2-by-1 vector:

B = [0.005; 0.1]

B = 2×1

0.0050 0.1000

then you cannot concatenate it horizontally with 0 as they don't have the same number of rows. [SL: removed an accidental repeat of the advice about "same number of rows."] If you defined a variable like this:

Z = zeros(size(B));

then this concatenation would be valid:

M = [B, Z; Z, B]

A = 4×2

0.0050 0 0.1000 0 0 0.0050 0 0.1000

[wissal zaher]

All clear now, thank you for the quick and helpful reply :)