Simulink Reference

Limitations on Indexing Operations

Matrix indexing operations for a matrix M are supported with limitations for the following types of expressions:

• M(i:j) where i and j change in a loop

• Embedded MATLAB never dynamically allocates memory for the size of the expressions that change as the program executes. The workaround is to use for loops as shown in the following example:

  • for i=1:10
        for j = i:10
            M(i,j) = 2 * M(i,j);
        end
    end
    

• M(i:i+k) where i is unknown but k is known

• In this case, since i and therefore i+k are not known, memory cannot be allocated for the numerical result. However, memory can be allocated for the following workaround:

  • M(i + (0:k))
    

  In this case, an unkown scalar value i is added to each element of the known index vector 0...k. This means that memory for k+1 elements of M is allocated.

• Initialization of the following style:

• for i = 1:10
      M(i) = 5;
  end
  

• In this case, the size of M changes as the loop is executed.

List of Unsupported Features

Limitations with Complex Numbers

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