import { pow , sin , tau } from '../internal' ; export const easeInOutElastic = ( n ) => { if ( ! n || n === 1 ) { return n ; } n *= 2 ; if ( n < 1 ) { return - 0.5 * ( pow ( 2 , 10 * ( n - 1 ) ) * sin ( ( n - 1.1 ) * tau / .4 ) ) ; } return pow ( 2 , - 10 * ( n - 1 ) ) * sin ( ( n - 1.1 ) * tau / .4 ) * .5 + 1 ; } ;