i wrote GUI with 2 pop up menus

hello there i wrote 2 pop up menus and i'm willing to get the values in the base workspace after running the GUI

this is my script for the poop up menus

if true
  % ccontent= cellstr(get(hObject,'string')); 
  stgrade=content(get(hObject,'value'));
if strcmp(stgrade,'S275')
   ppval='S275';

    else
     ppval='S355';
 end
 assignin('base','stgrade',ppval);

 Es=str2double(get(handles.Es, 'String'));
    % now we have to choose between different compressive strenghts C20-C50
    content2= cellstr(get(hObject,'string')); 
    congrade=content2(get(hObject,'value'));

    if strcmp(congrade,'C20')
         val='C20';
    elseif strcmp(congrade,'C25')
         val='C25';     
    elseif strcmp(congrade,'C30')
         val='C30';
    elseif strcmp(congrade,'C35')
         val='C35';
    elseif strcmp(congrade,'C40')
         val='C40';
    elseif strcmp(congrade,'C45')
         val='C45';
    elseif strcmp(congrade,'C50')
         val='C50';
      end
   assignin('base','congrade',val);
  end

now for the ppval i'm getting the value in the base workspace, but for the val it always says that Undefined function or variable "val" ... is there something wrong in my code or is it the val have a different function in MATLAB?

Answer 1

[Geoff Hayes]

Abdulla - I suspect that, for whatever reason, none of the conditions are being satisfied in your if/elseif code that would set val. And since you don't gave an else statement and don't initialize/define val, then the error may make sense. I suggest that you put a breakpoint at the line

 congrade=content2(...);

and the run your GUI. When the debugger pauses at this line, and then step through the ode line by line. What is congrade initialized too? Do any of the conditions get satisfied so that val is initialized? Also, you may want to consider adding an else clause so that val is initialized to something.