Passing input variables from .txt or .xlsx or .csv into MATLAB Standalone Application

Hi everyone,

I have a code that deals with mixed integer linear programming and creates an array based on measurements from site survey and some constraints and objective function that I supplied to it. At the begining, I supply the code with an array like this:

EV = [2 0 -2 2 1 -4 5 2 2 2 8 0 4 10 10 10 4 6 8 2 14 10 8 4 6 8 -2 -4 12 16 4 -4 3 0]';

Now this changes from site to site, it is a track geometry (measured versines) and this is example of one such survey. My code creates a second array with design versines that tells me what the track should look like to be optimized.

Now if I was to work in MATLAB only, it would be easy to simply change the EV array whenever we have a new survey and let the code calculate the design versine for different sites. However, I compiled my MATLAB code into Standalone Application so people without MATLAB can use it on their computers. Now is there a way I can create a .txt or .csv. or .xlsx file where they can write EV (data from their surveys) and the application will take the input from this file?

So far, when I compile my code, the input is always what it was at the point of compiling the software and i can't seem to find a way to change this.

Any help would be appreciated!

Answer 1

[Allen]

Kevin,

One approach would be to create a pushbutton object with a callback to browse and import data. The following callback example was setup in App Designer, but can also be accomplished in GUIDE with a few adjustments. It also was set to import data from a *.mat data file, but can easily be modified to work with a *.txt file.

% Button pushed function: pb_LoadEVFile
function pb_LoadEVFileButtonPushed(app, event)
    % I typically assign a default directory location that updates to the
    % last accessed directory when saving/loading files. However you can
    % make this whatever you prefer.
    startdir = app.Startdir; % string value for stored starting directory
    % Essentially what I use to define a default directory when my app
    % launches
    startdir = strcat("C:\Users\",getenv("USERNAME"),"\Documents\"); 
    if ~exist(startdir,"dir")
        startdir = "C:\";
    end
    
    % Prompt user to indicate filename and location
    [fn,pn] = uigetfile(fullfile(startdir,"*.mat"),"Select Data File");
    
    % Load data file and update App objects
    load(fullfile(pn,fn),"-mat","Data");
    
    % Run a quick check to verify the new EV data is in the correct format
    % before assigning it to your app data.
    nEV = []; % assign a 1x2 array with row, column dimensions required of EV data
    if isfield(Data,"Standard") && isequal(Data.Standard,nEV)
        app.EVData.Value = Data.Standard;
    end
end

[Kevin Syc]

Hi Allen,

thanks for this, great idea and nice solution. I modified it using some codes and documentation on internet and it works great.

Thank you

[Allen]

Glad to help!