--- a/scripts/linear-algebra/rref.m
+++ b/scripts/linear-algebra/rref.m
@@ -86,3 +86,43 @@
   k = find (used);
 
 endfunction
+
+%!test
+%! a = [1];
+%! [r k] = rref(a);
+%! assert(r, [1], 2e-8);
+%! assert(k, [1], 2e-8);
+
+%!test
+%! a = [1 3; 4 5];
+%! [r k] = rref(a);
+%! assert(rank(a), rank(r), 2e-8);
+%! assert(r, eye(2), 2e-8);
+%! assert(k == [1, 2] || k == [2, 1]);
+
+
+%!test
+%! a = [1 3; 4 5; 7 9];
+%! [r k] = rref(a);
+%! assert(rank(a), rank(r), 2e-8);
+%! assert(r, eye(3)(:,1:2), 2e-8);
+%! assert(k, [1 2], 2e-8);
+
+%!test
+%! a = [1 2 3; 2 4 6; 7 2 0];
+%! [r k] = rref(a);
+%! assert(rank(a), rank(r), 2e-8);
+%! assert(r, [1 0 (3-7/2); 0 1 (7/4); 0 0 0], 2e-8);
+%! assert(k, [1 2], 2e-8);
+
+%!test
+%! a = [1 2 1; 2 4 2.01; 2 4 2.1];
+%! tol = 0.02;
+%! [r k] = rref(a, tol);
+%! assert(rank(a, tol), rank(r, tol), 2e-8);
+%! tol = 0.2;
+%! [r k] = rref(a, tol);
+%! assert(rank(a, tol), rank(r, tol), 2e-8);
+
+%!error rref();
+