How can I change the size of the text in annotation, and place a border around it?

Hi! I would like to have a textbox on the outside of a polarplot, but with a border around it. It had a border around it when it was inside of the polarplot, but once I moved the textbox outside, the border disappeared. I would also like to make the textbox font size larger than the default. Here is my code so far:

figure
polarplot(FR{62})
annotation('textbox',[0.12, 0.80, 0, 0],'String',['Mutual Info = ',num2str(mutualInfoTotal(62))])
title('Mouse 28 Cell 62, Thalamus')

Answer 1

[Sindar]

You are setting the width and height of the box to 0.

I believe this should do it, but check here for other properties you may need/want to tweak

annotation('textbox',[0.12, 0.80, 0.1, 0.1],'String',['Mutual Info = ',num2str(mutualInfoTotal(62))],...
    'FontSize',24,'EdgeColor','k')