Change the name of a column in one gui from another

OBJECTIVE

I am trying to change the column names of a table named 'data' in the main gui from a sub-gui to the value of 'result' which should be a string.

CODE

result=strcat('(',char(B(1)),'^',num2str(cell2mat(PWR(itn,1))),')*(',char(B(2)),'^',num2str(cell2mat(PWR(itn,2))),')*(',char(B(3)),'^',num2str(cell2mat(PWR(itn,3))),')*',char(B(3+itn)));
pass_data{itn}=result

hMainGui = getappdata(0,'data');
set(hMainGui, 'ColumnName', pass_data);

ERROR

Error using ==> set Conversion to double from cell is not possible.

Note: The value of pass_data is equal to:

    '(b^1)*(c^2)*(d^0)*a'    '(b^1)*(c^2)*(d^3)*e'

[Walter Roberson]

Please show how you created "data".