--- a/libinterp/corefcn/data.cc	Mon Apr 04 10:31:48 2022 -0700
+++ b/libinterp/corefcn/data.cc	Mon Apr 04 10:50:26 2022 -0700
@@ -7245,53 +7245,6 @@
 %!error sort (1, 2, 3, 4)
 */
 
-// Sort the rows of the matrix @var{a} according to the order
-// specified by @var{mode}, which can either be 'ascend' or 'descend'
-// and return the index vector corresponding to the sort order.
-//
-// This function does not yet support sparse matrices.
-
-// FIXME: Is this function used anymore?  12/14/2015
-DEFUN (__sort_rows_idx__, args, ,
-       doc: /* -*- texinfo -*-
-@deftypefn {} {} __sort_rows_idx__ (@var{a}, @var{mode})
-Undocumented internal function.
-@end deftypefn */)
-{
-  int nargin = args.length ();
-
-  if (nargin < 1 || nargin > 2)
-    print_usage ();
-
-  if (nargin == 2 && ! args(1).is_string ())
-    error ("__sort_rows_idx__: second argument must be a string");
-
-  sortmode smode = ASCENDING;
-  if (nargin > 1)
-    {
-      std::string mode = args(1).string_value ();
-      if (mode == "ascend")
-        smode = ASCENDING;
-      else if (mode == "descend")
-        smode = DESCENDING;
-      else
-        error (R"(__sort_rows_idx__: MODE must be either "ascend" or "descend")");
-    }
-
-  octave_value arg = args(0);
-
-  if (arg.issparse ())
-    error ("__sort_rows_idx__: sparse matrices not yet supported");
-
-  if (arg.ndims () != 2)
-    error ("__sort_rows_idx__: needs a 2-D object");
-
-  Array<octave_idx_type> idx = arg.sort_rows_idx (smode);
-
-  // This cannot be ovl(), relies on special overloaded octave_value call.
-  return octave_value (idx, true, true);
-}
-
 static sortmode
 get_sort_mode_option (const octave_value& arg)
 {