((relax)
       (let ([graph (first Largs)]
             [pos (second Largs)])


         (for ([(nodeid neigh) (in-hash graph)]) ;analyse chaque sommet
           (set! force-t (make-vect 0 0))
           (for ([(nodeid2 neigh2) (in-hash graph)]) ;deroule la liste de id/voisins
             (if (and (not(equal? nodeid nodeid2)) (set-member? neigh2 nodeid));force-m aux voisins
                 (begin (set! force-t (vect-sum force-t (force-m pos nodeid nodeid2)))
                        (set! force-t (vect-sum force-t (force-e pos nodeid nodeid2))))
                 (set! force-t (vect-sum force-t (force-e pos nodeid nodeid2)))));dans tous les cas force-e)
           (hash-set! pos nodeid (vect-sum (vect-scalar c4 force-t) (hash-ref pos nodeid))))))