Changing from "int" to Series<int>

[cre8able]

I have an indicator where I want to store values for each bar so I want to use a Series<int>.

When I use "int" values for ema200SlopeA it works fine. But when I try to switch to Series<int> for ema200SlopeA, I get this error

"Indicator 'Stack': Error on calling 'OnBarUpdate' method on bar 300: Object reference not set to an instance of an object."

below is the code where I initialize and then calculate the values for ema200SlopeA. When I use just an "int" it works fine. When I switch to Series I get the error.

I have this statement in so that I don't get an out of range error " if (CurrentBar < 300) return; "

it seems simple, but I'm missing something

thanks

public class Stack : Indicator
    {

        private Series<int>        ema200SlopeA;
        private int             ema50SlopeA;//, ema200SlopeA;
        private int             ema50SlopeB, ema200SlopeB;&#8203; 

        protected override void OnBarUpdate()
        {
            if(DateTime.Today > new DateTime(2023, 09, 01, 0, 0, 0)) return;    //  filter to stop running if old version

            ema50A = EMA(BarsArray[1],50);           // these are type EMA
            ema50B = EMA(BarsArray[2],50);
            ema200A = EMA(BarsArray[1],200);
            ema200B = EMA(BarsArray[2],200);


            if (CurrentBar < 300) return;        

            trendDirection = 0;

            if(ema50A[0] > (ema50A[lookBack] + TickSize/s50))
                ema50SlopeA = 1;
            else if(ema50A[0] < (ema50A[lookBack] - TickSize/s50))
                ema50SlopeA = -1;
            else
                ema50SlopeA = 0;

            if(ema200A[0] > ema200A[lookBack] + TickSize/s200)
                ema200SlopeA[0] = 1;    
            else if(ema200A[0] < ema200A[lookBack] - TickSize/200)
                ema200SlopeA[0] = -1;    
            else
                ema200SlopeA[0] = 0;
&#8203; 

[NinjaTrader_BrandonH]

Hello cr8able,

Thanks for your post.

When creating a custom Series object, you would need to make sure you are instantiating the custom Series object in OnStateChange() when the State == State.DataLoaded.

See this help guide page for more information about working with custom Series objects: https://ninjatrader.com/support/help...t8/seriest.htm

[cre8able]

Got it. Thank you