using .mat and .m files in GUI

Background: I am building a GUI which uses uigetfile to allow user to select .mat file containing data of interest. The .mat file contains some matrices, from which the GUI will select one with a certain name and pass it to a function outside the GUI.

My question: How can I get the GUI to pass the matrix of interest from a .mat file that the user selects to an outside function? I began by finding the handles of the outside function by

functionhandle=@function;

[output]=functionhandle(matrix from .mat file, etc.);

Thanks

Answer 1

[Walter Roberson]

http://matlab.wikia.com/wiki/FAQ#How_can_I_share_data_between_callback_functions_in_my_GUI.3F

Answer 2

[Fangjun Jiang]

a=load('datafile.mat');
VarName=fieldnames(a);

will give you all the variable names in datafile.mat. Then, select a variable name and pass the value to your function.

MyVarName=VarName{1};
functionhandle(a.(MyVarName))