How to export struct saved in workspace to text file

Hi, I have a struct with some fields inside. I want to be able to export the struct (or at least 2 of the fields inside) to a text file. Any help would be appreciated. Thanks

[Walter Roberson]

What output format do you need ?

Have you considered Json encode?

[ProgramNerd]

Text file unfortunately

[Walter Roberson]

json is a text file

[ProgramNerd]

As you can tell, I haven't used nor have knowledge on json. As long as I can get a .txt file at the end with the fields in a readable format within the text file I really dont care how I get it to work

[Walter Roberson]

see https://www.mathworks.com/help/matlab/ref/jsonencode.html#mw_69b38ba2-26d1-4025-a426-d1bf8ca939a7

[ProgramNerd]

Great thank you, definetely something I need to look into and expand my knowlegde on

Answer 1

[Abderrahim. B]

Convert to table and then wrtie to text file:

% Example 1: convert and write to table
S.Str = 'I Love MATLAB'

S = struct with fields:
    Str: 'I Love MATLAB'

S.Date = datetime("now")

S = struct with fields:
     Str: 'I Love MATLAB'
    Date: 01-Aug-2022 14:21:48

Stb = struct2table(S)

Stb = 1×2 table
         Str                 Date        
    _____________    ____________________

    I Love MATLAB    01-Aug-2022 14:21:48

writetable(Stb, "Stb.txt")

Edit:

• based @Walter Roberson reply, jsonencode is a good option in your case.

% Example 2: using jsonencode and fprintf
clear
S.A1 = [9.9, 9900];
S.A2 = [8.8,  7.7 ; ...
      8800, 7700];

S = jsonencode(S, "PrettyPrint", true)

S = 
    '{
       "A1": [
         9.9,
         9900
       ],
       "A2": [
         [
           8.8,
           7.7
         ],
         [
           8800,
           7700
         ]
       ]
     }'

• Export to text file

I do not know about your struct, so I'm skipping formatSpec.

NB: fprintf has an option called formatSpec that you may need to set as first argument to fprintf.

fileID = fopen('myS.txt','w');
nbytes = fprintf(fileID,S) ;
fclose(fileID);

Hope this helps

[ProgramNerd]

Thank you for your response, I got the following as an error, please could you help

Error using struct2table (line 97)

Input structure is a scalar, but its fields have different numbers of rows. If you intended to create a table with

one row, set 'AsArray' to true.

[Abderrahim. B]

You can solve this by setting AsArray to true :

Stb = struct2table(S, "AsArray",true)

[ProgramNerd]

Thank you that works, but the text file isnt very usable. Is there a way to get the specific fields within the struct? I have tried but this doesnt seem to work

myTable = struct2table(data.var, "AsArray", true);

[Abderrahim. B]

@ProgramNerd edited my answer. Check it out.

[ProgramNerd]

Great thank you, so much nicer now. Really appreicated all the help