How to set file name to load based on user input

Hi,

I have a GUI created in guide which contains a pop-up menu with various options available, e.g. 'test1', ''test2', 'test3', these are names of .mat files the user might want to load. The GUI also has a push button which when pressed would load the selected .mat file from the pop-up menu and add some data to it. My code for loading the .mat file currently looks like this..

    foo = get(handles.popup2,'Value');
    if foo == 1
      fname = 'test1'
    elseif foo == 2
      fname = 'test2'
    elseif foo == 3
      fname = 'test3'
    end
    folder = 'C:\Documents and Settings\usr\My Documents\MATLAB\'
    Database = load(fullfile(folder,fname)

The problem is that the code loads a 1x1 struct of the entire contents of the directory. Where am I going wrong?

Thanks in advance, Joel

Answer 1

[Walter Roberson]

foo_names = get(handles.popup2, 'String');
foo = get(handles.popup2,'Value');
if isempty(foo)
  fprintf(2, 'You need to select a value\n');
  return
end
fname = foo_names{foo};
folder = 'C:\Documents and Settings\usr\My Documents\MATLAB\';
full_name = fullfile(folder,[fname, '.mat']);
try
  Database = load(full_name);
catch
  fprintf(2, 'Opps, I failed to load the file %s\n', full_name);
  return
end

Now Database is going to be a struct with one field for each variable stored in the .mat file. This is how load() is defined when you ask it to return a value. You can refer to appropriate fields of the structure

Database.mydata

for example to access the variable stored as mydata in the .mat file.

[Joel Poder]

Hi Walter, thanks for the quick response. Unfortunately, your answer is still giving the same result. Database is returning a struct with a field for every variable stored in the C:\Documents and Settings\usr\My Documents\MATLAB\ directory. If I try

Database.test1

All I get is a return of the filename, e.g.

test1.mat

[Walter Roberson]

Please show

 whos -file test1.mat

Also please show what full_name comes out to be.