MATLAB: Num2str error in textbox

Question

Hello! I am very new to matlab and am trying to put a text box in a plot with the value of a variable. The variable is located in a cell array. This is my code:

figure
polarplot(FR{4})
annotation('textbox','String','Mutual Info =',num2str(mutualInfoTotal{4}))

But I am getting an error message that says "Error using matlab.graphics.shape.TextBox. Invalid parameter/value pair arguments."

If I want to create a plot with a textbox in it that says 'Mutual Info =,' then call the mutual info value of a variable, what would be the correct code?

Answer 1

Try

annotation('textbox','String',['Mutual Info =',num2str(mutualInfoTotal{4})])

or

annotation('textbox','String',sprintf('Mutual Info = %s',num2str(mutualInfoTotal{4})))

or if mutualInfoTotal{4} is a single, scalar value,

annotation('textbox','String',sprintf('Mutual Info = %d',mutualInfoTotal{4})) % for integer
% or
annotation('textbox','String',sprintf('Mutual Info = %.3f',mutualInfoTotal{4})) % for 3 dp