Importing data from a text file in a standalone GUI windows application

Hi there,

I've recently compiled my first standalone GUI. The program first shows an option window from which you select one of two options, and then depending on the option opens a second GUI. This second GUI imports data from text files stored in a sub-folder that I included in the 'additional files' using MCC when I built the thing.

This import works perfectly well when run from the command window, but fails miserably in the standalone. There's no error message, just a 'ding' that tells me something's gone wrong, and then it freezes. I'm using cd to change to the subfolder and importdata to import the text file. Can anyone help?

I've pasted a part of my code below...

First I set up all the buttons and stuff, which runs fine. The user is then prompted to input a string, and then press a button. On pressing the button, this executes:

S.R = get(S.ed(3),'String'); 

S.fileID=sprintf('000%s-ant_time_X.txt',S.R);
      S.fileID2=sprintf('000%s-antstat.txt',S.R);
      S.fileID3=sprintf('000%s-antangle.txt',S.R);
      S.ID=sprintf('000%s',S.R);
      s=str2double(sprintf('%s%s',S.R(1),S.R(2)));
  end

   cd data_for_gui

        data=importdata(S.fileID);
        datamat=(data.data);
        T=datamat(:,1);
        X=datamat(:,2);
        Y=datamat(:,3);

This is the point at which I get 'ding'. A similar problem occurs in the other GUI which opens after the initial open window when the code requires importdata

Any advice much appreciated!

Answer 1

[Walter Roberson]

Is the file format known ahead of time? If it is, then when you are developing the code, use uiimport() and use its option to generate code that understands that file format, and incorporate that code instead of importdata().

You should also consider using textscan() instead of importdata()

[Catherine]

Hi Walter, thanks for the suggestion - is textscan simply faster, or is importdata less compatible with standalone apps?

The file format is consistent, and runs fine in when I run the program from the command window, so I don't think the problem is there.

I just had a thought that perhaps the problem is using *cd* - is the current directory not the one with my second GUI? If not, that would explain why I'm unable to import anything! I was about to try recompiling it with the necessary textfiles in the same folder as the .m file.

[Walter Roberson]

The current directory will seldom be the one you expect (unless you've had a lot of practice with the compiler.)

http://www.mathworks.com/support/solutions/en/data/1-6OFV37/

http://www.mathworks.com/help/toolbox/compiler/ctfroot.html

textscan() should in theory be faster.