import { ROC as ROCIndicator } from 'technicalindicators';
import { OHLC, OHLCEnum } from '../types';
import { IndicatorInput, Indicator } from './base-indicator';
export interface RateOfChangeInput extends IndicatorInput {
    period?: number;
    source?: OHLCEnum;
}
/**
 * The rate of change (ROC) is the speed at which a variable changes
 * over a specific period of time. ROC is often used when speaking
 * about momentum, and it can generally be expressed as a ratio between
 * a change in one variable relative to a corresponding change in another;
 * graphically, the rate of change is represented by the slope of a line.
 * The ROC is often illustrated by the Greek letter delta.
 */
export declare class ROC implements Indicator {
    indicator: ROCIndicator;
    source: OHLCEnum;
    /**
     * @param {OHLC[]} series candles series
     * @param {OHLCEnum} source source of values
     * @param {number} period period for indicator
     */
    constructor(series: OHLC[], source?: OHLCEnum, period?: number);
    /**
     * Retrieve ROC values for instance
     * @return {number[]} values for instance data
     */
    getResults(): number[];
    /**
     * Calculate ROC to next tick
     * @param {OHLC} candle new candle to add to series
     * @return {number | undefined} next ROC value or undefined if period is
     * greater than actual series length
     */
    next(candle: OHLC): number | undefined;
    /**
     * Create instance from data
     * @param {RateOfChangeInput} input input data
     * @return {ROC} ROC instance
     */
    static generator({ series, source, period, }: RateOfChangeInput): ROC;
    /**
     * Get ROC values from input
     * @param {RateOfChangeInput} input input data
     * @return {number[]} ROC values
     */
    static calculate(input: RateOfChangeInput): number[];
}