Derivative Oscillator

using System;
using cAlgo.API;
using cAlgo.API.Indicators;
using cAlgo.API.Internals;

namespace cAlgo
{
    [Levels(0)]
    [Indicator(IsOverlay = false, AccessRights = AccessRights.None)]
    public class mDerivativeOsc : Indicator
    {
        [Parameter("RSI Period (10)", DefaultValue = 10, MinValue = 2)]
        public int inpPeriodRSI { get; set; }
        [Parameter("Period First (5)", DefaultValue = 5, MinValue = 2)]
        public int inpPeriodFirst { get; set; }
        [Parameter("Period Second (3)", DefaultValue = 3, MinValue = 2)]
        public int inpPeriodSecond { get; set; }
        [Parameter("Period Smooth (9)", DefaultValue = 9, MinValue = 2)]
        public int inpPeriodSmooth { get; set; }

        [Output("Derivative ", LineColor = "Black", PlotType = PlotType.Line, Thickness = 1)]
        public IndicatorDataSeries outDerivative { get; set; }
        
        private RelativeStrengthIndex _rsi;
        private MovingAverage _first, _second, _smooth;
        private IndicatorDataSeries _result;
        

        protected override void Initialize()
        {
            _rsi = Indicators.RelativeStrengthIndex(Bars.ClosePrices, inpPeriodRSI);
            _first = Indicators.MovingAverage(_rsi.Result, inpPeriodFirst, MovingAverageType.Exponential);
            _second = Indicators.MovingAverage(_first.Result, inpPeriodSecond, MovingAverageType.Exponential);
            _smooth = Indicators.MovingAverage(_first.Result, inpPeriodSmooth, MovingAverageType.Simple);
            _result = CreateDataSeries();
        }

        public override void Calculate(int i)
        {
            _result[i] = _second.Result[i] - _smooth.Result[i];
            
            outDerivative[i] = _result[i];
        }
    }
}