hello you..
When you use Matlab Ra2007a, We have got Gui in the Matlab.
At Gui interface of code. You need write code and add code in Gui, That's ok.

you see " Add", It is a Buttons, When You created this Gui, and add your code in Buttons, That's OK?

(http://i280.photobucket.com/albums/kk189/ngohaibac_dot_net/Matlab_TUT/Maltab_tutorial_009.gif)