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Gain dimension failure ending in error

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At first, I built the following control circle:
Gain window
As you can see x is a (4,1)-vector and in the picture below you can see G is a (1,4)-Matrix.
Multiplying a K.*u means G.*x means in dimensions: (1,4)*(4,1)=(1,1). But (however) a (4,4)-matrix is the solution, which leads to an error, cos I cant add 4,4 and a scalar. So why is (4,4) the solution or what did I miss in the gain window? (I set element wise multiplication K.*u)
  1 Comment
Lennart
Lennart on 12 Jun 2024
Edited: Lennart on 12 Jun 2024
Sorry I got it myself... I have to set Matrix(K*u) in the G window, so (1,4)*(4,1)=(1,1) and it does what it should do.

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Accepted Answer

Aquatris
Aquatris on 12 Jun 2024
Edited: Aquatris on 12 Jun 2024
G gain is set for element wise multiplication instead of matrix multiplication, hence (1,4).*(4,1) = (4,4).
x = ones(4,1);
G = ones(1,4);
size(G.*x) % element wise multiplication
ans = 1x2
4 4
<mw-icon class=""></mw-icon>
<mw-icon class=""></mw-icon>
size(G*x) % matrix multiplication
ans = 1x2
1 1
<mw-icon class=""></mw-icon>
<mw-icon class=""></mw-icon>
Set the "Multiplication"drop down menu for the G gain to 'matrix multiplication'.

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