Pleaaaase help me !!!! i didn't got a result with this code.

Af=diag([-10 -10])
Da=[4.3970 33.4300;
    -0.4182 -1.1780]
Ba=[0 0;6.8060 9.2750;
    -1.7700 -0.7986;
    0 0;0 0;
    6.1130 -42.0300;
    0 0;
    -20.2700 -13.2900]
B=[Ba -Af*Da]

Af =

     -10     0
       0   -10

Da =

      4.3970   33.4300
     -0.4182   -1.1780

Ba =

           0         0
      6.8060    9.2750
     -1.7700   -0.7986
           0         0
           0         0
      6.1130  -42.0300
           0         0
    -20.2700  -13.2900

Error using horzcat
Dimensions of matrices being concatenated are not consistent.

Answer 1

[Walter Roberson]

Your Ba is 8 x 2.

Your Af and Da are 2 x 2, and when you matrix-multiply a 2 x 2 with a 2 x 2 you get a 2 x 2, so -Af*Da is 2 x 2.

You are trying to create a matrix in which the first two columns have 8 rows, but the last two columns contain only 2 rows.

What size of output were you expecting?

[yousra yahia]

Af=diag([-10 -10]) Da=[4.3970 33.4300; -0.4182 -1.1780] Ba=[0 0;6.8060 9.2750; -1.7700 -0.7986; 0 0;0 0; 6.1130 -42.0300; 0 0; -20.2700 -13.2900] B=[Ba ; -Af*Da]

B =

         0         0
    6.8060    9.2750
   -1.7700   -0.7986
         0         0
         0         0
    6.1130  -42.0300
         0         0
  -20.2700  -13.2900
   43.9700  334.3000
   -4.1820  -11.7800

[yousra yahia]

Thank you i get the result.