MATLAB: What is the output of a MERGE block that follows an IF Action Subsystem when none of the IF or ELSEIF conditions are met

Question

I have a merge block that merges the outputs of the IF Action Subsystems. I do not have an ELSE Action Subsystem. In the event that one of the IF or ELSEIF conditions are satisfied, the output of the MERGE block would be that of the Action Subsystem whose condition was satisfied. However, in the event that none of the conditions are met, none of the Action Subsystems would be executed. In this case what would be the output of the MERGE block?

Answer 1

The Simulink documentation is missing information on how the output of the MERGE block is determined when none of the branches that are input to the MERGE block have a valid output at a given time instant during the simulation.

At a given simulation time step, if none of IF/ELSEIF conditions are met, then the Merge block's output equals the most recently evaluated output among the Action Subsystem blocks.