Use mldivide in SIMULINK

I am stuck with the following Problem: I have to solve a System of linear equations:

A*x = b (where A is 25x25 Matrix and b and x are 25x1 vectors)

at every timestep of a SIMULINK model. I am currently doing so with an embedded MATLAB function Block which does simply something like this:

function x = fcn( A , b ) %#codegen

x = mldivide(A,b);

end

The Problem is that I need to get rid of the MATLAB function Block. It really feels like a stupid question but is there a possibility to execute the mldivide-order with a SIMULINK Block?

Thank you so much in advance

Answer 1

[Sebastian Castro]

Since you're using a square A matrix, you should be able to use the Divide block (Simulink > Math Operations). If you set its "Multiplication" parameter to "Matrix", a divide sign means you're passing in a matrix inverse.

Sebastian

[Maximilian Binzler]

Thank you so much for this answer, it is really helpful! In the Matlab Documentation for mldivide is written "If A is a square matrix, A\B is roughly equal to inv(A)*B, but MATLAB processes A\B differently and more robustly." Do you know if the Simulink divide Block is as efficient as mldivide?

[Christoph Wellnhofer]

@Maximilian Binzler you can also use the singular value decomposition Simulink block which also works for non-square matrices and has better numerical stability.