From your query, I understand that you are encountering an error when using polarplot after the clf command. I tried to reproduce the issue but couldn't encounter any errors during my simulation. If you are still experiencing the issue, I recommend upgrading your MATLAB version.
Please look into this query on the MATALB Answers forum as this might be similar to your case:
For more information on Polar Plots, please refer to the below documentation:
Hope this helps!
