only , benchmark...
(defun test1 (n l )
(setq l (vl-sort l (function <)))
(while (< (cadr l) n) (setq l (cdr l)))
(if (< (abs (- n (car l))) (abs (- n (cadr l))))
(car l)
(cadr l)
)
)
Benchmarking .................Elapsed milliseconds / relative speed for 16384 iteration(s):
(TEST1 N L)..........1329 / 1.08 <fastest>
(NEAREST133 N L).....1438 / 1 <slowest>