Bar out of range

[swcooke]

As a test and to learn, I am trying to create a Custom Series, assign values to it, and then Print() those values back out from inside of OnRender(). I am getting the error:

Time	Category	Message
9/10/2018 5:40:16 PM	Default	Indicator 'Sample custom series': Error on calling 'OnRender' method on bar 342: You are accessing an index with a value that is invalid since it is out-of-range. I.E. accessing a series [barsAgo] with a value of 5 when there are only 4 bars on the chart.

Any help would be appreciated.

[NinjaTrader_Jim]

Hello swooke,

Thanks for your post.

In your code you are using a barsAgro reference in OnRender which would throw the error you are receiving.

for (int idx = ChartBars.FromIndex; idx <= ChartBars.ToIndex; idx++)
{
	Print(xlkClose[idx]);	// This is a barsAgo reference and not a reference to an absolute index.
}

In OnRender, it would be recommended to use absolute bar indexes (similar to CurrentBar) than relative barsAgo references like we use in OnBarUpdate().

From the OnRender documentation:

5. Unlike market data events and strategy order related events, there is NO guarantee that the barsAgo indexer used for Series<T> objects are in sync with the current bars in progress. As a result, you should favor using an absolute index method to look up values (e.g., <series>.GetValueAt(), Bars.GetOpen(), etc)

OnRender - https://ninjatrader.com/support/help.../?onrender.htm

Values from absolute indexes can be retrieved from Series<t> objects by using the GetValueAt method. To observe the differences you may see in OnBarUpdate that Close.GetValueAt(CurrentBar) would be the same as Close[0];

GetValueAt - https://ninjatrader.com/support/help...getvalueat.htm

I have included a link to an Ichimokou Cloud indicator I wrote that processes 2 custom Series<doubles> to draw a region. You can observe how this indicator uses absolute references in place of barsAgo index.

Ichimokou Cloud - https://ninjatrader.com/support/foru...tid=-1&lpage=1

I've also provided a link to our Using SharpDX for custom rendering page of the help guide for important tips and best practices while using SharpDX.

Using SharpDX for custom rendering - https://ninjatrader.com/support/help..._rendering.htm

Please let us know if we can be of further assistance.