MATLAB: How to acceess variable from another function in GUI

acessibilitygui

I have a question say i building a gui that's loads file if data(array of double ) and calculates and plots a result so in gui,there is 'load file' push button,which has a callback function 'calculate and plot' push button,which also has a function callback
how can i access a data in 'calculate and plot' function callback ? when i doing debug there is no such variable ! F1 !