Question

In Octave I would like to save a struct to a textfile where the name of the file is decided during the runtime of the script. With my approach I always get an error:

expecting all arguments to be strings. 

(For a fixed filename this works fine.) So how to save a struct to a file using a variable filename?

clear all;
myStruct(1).resultA = 1;
myStruct(1).resultB = 2;
myStruct(2).resultA = 3;
myStruct(2).resultB = 4;

variableFilename = strftime ("result_%Y-%m-%d_%H-%M.mat", localtime(time()))

save fixedFilename.mat myStruct; 
% this works and saves the struct in fixedFilename.mat

save( "-text", variableFilename, myStruct); 
% this gives error: expecting all arguments to be strings

Answer 1

In Octave, When using save as a function you need to do something like this:

myfilename = "stuff.txt";
mystruct = [ 1 2; 3 4]
save("-text", myfilename, "mystruct");

The above code will create a stuff.txt file and the matrix data is put in there.

The above code will only work when mystruct is a matrix, if you have a cell of strings, it will fail. For those, you can roll your own:

 xKey = cell(2, 1);
 xKey{1} = "Make me a sandwich...";
 xKey{2} = "OUT OF BABIES!";
 outfile = fopen("something.txt", "a");
 for i=1:rows(xKey),
   fprintf(outfile, "%s\n", xKey{i,1});
 end
 fflush(outfile);
 fclose(outfile);