Why do I receive an error when using a second Matrix Multiply block from the DSP Blockset 5.0 (R13) with unconnected inputs in my model?

I have a model with two Matrix Multiply blocks in it. One of them has an unconnected input. When I update the diagram or try to run the model, I get an error:

 Error in port widths or dimensions.  

 Output port 1 of block 'modulator1_TMW_bug/Multiply Matrix' has 3 elements.  

 This port does not accept the dimensions (or orientation) specified by the output signal

Answer 1

[MathWorks Support Team]

This bug has been fixed for Release 14 (R14). For previous releases, read below for any possible workarounds:

This is a bug in the DSP Blockset 5.0 (R13) in the way that the Matrix Multiply block handles missing inputs.

To work around this issue, you will need to connect the inputs of the Matrix Multiply block before running the simulation or updating the diagram.