Indicator doesn't use updated DataSeries values

[jeffery]

Hi,
I am having trouble with a DataSeries Object that holds Close prices. I hope that somebody can help.

In a strategy, I Set the prices in each OnBarUpdate() . At various times I perform a While loop which adjusts and resets the most current price in the DataSeries Object. The purpose of the loop is to adjust the price until an indicator which is based on the price changes to a known value. Once that happens I then have the price at which the indicator will have the specified value in the future. I intend to use the resultant price as the trigger point for a future trade.

I can correctly extract the prices while in the strategy. The problem occurs when I call an indicator using the prices in the DataSeries Object. It appears that the indicator uses only the first price entered for the current bar and not any of the subsequent prices that replace it, so returning the same values on every call in the loop.

The following code illustrates the problem.
#region Variables
private DataSeries closePrice;
#endregion

protected override void Initialize()
{
closePrice = new DataSeries(this);
}

protected override void OnBarUpdate()
{
if (CurrentBars[0] <= BarsRequired) return;
closePrice.Set(Close[0]);
if (CurrentBar != 10) return; // Only do the test for bar 10

Print(closePrice[0].ToString("0.0000")+", EMA value = "+
EMA(closePrice,5)[0].ToString()); // Use a simple EMA as example

closePrice.Set(Close[0]+1.0); // Save and print for a different price value

Print(closePrice[0].ToString("0.0000")+", EMA value = "+
EMA(closePrice,5)[0].ToString());
}

Output file contains
1.0609, EMA value = 1.0646201198249
2.0609, EMA value = 1.0646201198249

Any suggestions would be most welcome. Thanks, John

[NinjaTrader_Joydeep]

Hello John,
Thanks for writing in and I am happy to assist you.

It’s due to how NinjaTrader calls any indicator internally and beyond what we could describe or support. But if you dispose the EMA before calling it again you will get the correct value.

Print(closePrice[0].ToString("0.0000")+", EMA value = "+
EMA(closePrice,5)[0].ToString()); // Use a simple EMA as example

closePrice.Set(Close[0] + 1.0); // Save and print for a different price value


EMA(closePrice, 5).Dispose();	//dispose the ema to recalculate the values	

Print(closePrice[0].ToString("0.0000")+", EMA value = "+
EMA(closePrice,5)[0].ToString());

Also please do remember when you reassign the custom data series (closePrice), the previous values (i.e. closePrice[1], closePrice[2] … etc) are set to that reassigned value. So please do take care on that too.

Please let me know if I can assist you any further.

[jeffery]

Just to let you know that I really, really appreciate your help.

It works as described.

Thank you so much,

John

[NinjaTrader_Joydeep]

Hello John,
Glad to know it worked.
Please let me know if I can assist you any further.