/**
 *
 * @param high
 * @param low
 * @param close
 * @param period
 * @param coef
 * @param size
 * @returns [ce_high, ce_low]
 */
export declare function ce(high: Array<number>, low: Array<number>, close: Array<number>, period: number, coef: number, size?: number): Promise<number[][]>;