Error in Sliding Mode Controller Code

It sounds like the error may be occurring due to a hidden dimension mismatch when the blocks are connected, or possibly because the output dimensions aren’t being fully defined in all execution paths within your MATLAB Function block. Even if each function works independently, when you connect them the signal dimensions might not be properly propagated. Here are a few suggestions to help troubleshoot and resolve the issue: 1. Verify that all inputs coming into the MATLAB Function block have explicit dimension and data type definitions. You can set these in the block’s “Ports and Data Manager” so that Simulink knows exactly what sizes to expect. 2. Inside your MATLAB Function block, ensure that every code path assigns a value to the output variable with consistent dimensions. You might want to initialize your output at the beginning of the function to a preallocated array with the desired size. For example:

function output = yourFunction(C, f) % Preallocate output to a specific size (e.g., if output should be 3x1) output = zeros(3,1); % Then, perform the computation output = C * f; % Ensure that the dimensions of C and f match appropriately end

3. Double-check that the matrices C and f indeed have compatible dimensions at runtime. Sometimes, when integrating different blocks, the data type or dimension inference might change. You can add temporary assertions or use the disp() function (or coder.internal.assert if code generation is involved) to log their sizes. 4. If one of the matrices (say, f) is generated dynamically or passed through multiple blocks, consider using the Simulink Diagnostic Viewer to inspect the actual sizes during simulation.

By ensuring that the inputs have well-defined dimensions and that the output is consistently assigned, you should be able to resolve the error.

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