App Designer - Writing Data to Txt File

I am building a GUI using app designer and I want to be able to input data into the GUI and then write it into a text file.

The data should write as a vector

I used fprintf, but I'm no expert on app designer and it didn't seem to work.

Does anyone have an example of how to write data to a text file using app designer?

Answer 1

[Reshma Nerella]

Hi,

To write data into a file, use fopen to open file. It gives a fileID to identify the open file.

Now you can write data into the file using fprintf and fileID.

Close the file using fclose after writing data into it.

For instance,

v = 1:5 %vector you want to insert

Now write it in the text file

f = fopen('filename.txt','w'); %Open or create new file for writing. Discard existing contents, if any.
fprintf(f,'%d\n',v); % Writes every element of vector in a new line in the file
fclose(f); % Close the file

Hope this helps!

[I]

I think I get how this would work, but it seems like v needs to be pre defined whereas I would like to define the variables in the form of a vector after running the app. Is it possible to proceed in this order:

1. Run the app
2. Define the vector
3. Then right the matrix to the text file

Thanks for your input so far.