MATLAB: Problem with the “get” function to get dat from a handles structure in a GUI

Question

I am working on a GUI and have some trouble. Here is the code that I am using:

function etireur_compresseur_gui_OpeningFcn(hObject, eventdata, handles, varargin)
  set (handles.input_lambda,'String','1057e-9')
  handles.lambda = str2double(get(handles.input_lambda,'String'));
  % Update handles structure
  guidata(hObject, handles);

Now here is the problem : when I type in the command window

get(handles.input_lambda)

Everything is fine and no pb but when I type :

get(handles.lambda)

Then I get this error :

??? Error using ==> get
Invalid handle object.

Does anyone have an idea?

Answer 1

handles.lambda is a number, not a graphics object, so get won't work on it. Just type handles.lambda at the command line instead of get(handles.lambda) to see it's contents.

Here is the line that is setting handles.lambda to a number instead of an object.

handles.lambda = str2double(get(handles.input_lambda,'String'))