Best practice to check series bounds?

[joejoeagogo]

What is the best practice to avoid constantly getting crashes from indexing into a series (say an indicator value in the past) that doesn't yet exist?

Thanks

[bltdavid]

Best practice?

Well, first things first,
Add some guard at the start of your OnBarUpdate,

if (CurrentBar < 10)
    return;

Where 10 represents the maximum number of past
bars you'll ever need to look at. That value '10' could
smaller or larger, it just depends on your logic.

This kind of guard code should fix the vast majority
of issues when looking at past bars.

[If you have additional data series, there are other
checks they may need to be done.]

Just my 2˘.

[NinjaTrader_BrandonH]

Hello joejoeagogo,

Thanks for your post.

bltdavid is correct.

A CurrentBar check could be used in your script's logic to ensure that a certain number of bars have been processed before the script begins calculation. A CurrentBar check would look something like this.

if (CurrentBar < 10)
    return;

This would check to make sure that 10 bars have processed before the script begins its calculations.

See the help guide documentation below for more information.
CurrentBar - https://ninjatrader.com/support/help...currentbar.htm
CurrentBars - https://ninjatrader.com/support/help...urrentbars.htm
Make sure you have enough bars - https://ninjatrader.com/support/help...nough_bars.htm

Let us know if we may assist further.