warning doesn't print sprintf characters unless it is given more than one...

warning doesn't print sprintf characters unless it is given more than one argument. hence use sprintf

src/utilities/x13/select_x13_binary.m

@@ -59,7 +59,9 @@ end
 
 if ~exist(x13_binary, 'file')
     if warn_only
-        warning('X13 binary is not available.\nIf you are under Debian or Ubuntu, you can install it through your package manager, with ''apt install x13as''.\nIf you are under Windows or macOS, this probably means that you did not install the dseries toolbox through an official package.\n');
+        warning(sprintf(['X13 binary is not available.\n' ...
+            'If you are under Debian or Ubuntu, you can install it through your package manager, with ''apt install x13as''.\n' ...
+            'If you are under Windows or macOS, this probably means that you did not install the dseries toolbox through an official package.\n']));
         x13_binary = '';
     else
         error('Can''t find X13 binary');