Trouble with integrating functions with loop and switch

 *This is what I have so far below. I need to know how i can use functions to help calculate the area and circumference of the circle when the menu bar comes up. How do I add Function circleArea() and Function circleCircum() that will accept the radius and reveal the area and circumference respectively.* 

 flag =0;

%Calculation

 while (1)

 choice=menu('Circle and Cylinder', 'Enter the radius','Display the area', 'Display the circumference','Exit');

 switch(choice)

 case 1

 r=circleInfo();

 flag=1;

 case 2

 if (flag==0)

 disp('you need to enter the radius first');

 else

 area=circleArea(r);

 end

 case 3

 if (flag==0)

 disp('You need to enter the radius first')

 else 

 circumference = circleCircum(r)

 end

 end

 end

[Ashish Gudla]

By converting your script into a function (lets say "my_fun"), you can add the definitions for the other functions "circleArea" and "circleCircum" after the end of your "my_fun" function.

Also you might want to consider "inputdlg" (see doc) and "msgbox" (see doc) to accept the radius and display the calculated values.