Error on calling "On BarUpdate" Indicator

[rmaron]

HI,

I'm trying to write a simple indicator, that compares the current bar high value with the previous bar high value as follows:
if (High[0]<High[1])
{
res=100;
}

However, I'm getting the run time error: Error on Calling OnBarUpdate....on bar 0. You are accessing an index with a value that is invalide since its out of range.
1. Can someone explain why I get that error message?
2. Is there a way to know how many bars are loaded into the cart (i.e. In case I need to look back to find whether a condition existed in the past).

Thank you.

[NinjaTrader_Lance]

Hello,

it sounds like you're already on the right track for identifying the error.

You will want to add a CurrentBar check at the start of your OnBarUpdate() to ensure enough bars have been loaded.

http://www.ninjatrader.com/support/helpGuides/nt7/index.html?currentbar.htm

Let me know if I can be of further assistance.

[rmaron]

Thank you for the quick response.
As you suggested, I checked the value of CurrentBar and is really = 0.
However, I don't really understand why.
My Chart contain way more the 0 bars.
Any idea?


Adding later....:
Ok...I think I understand now.
I need to add the condition:
if (CurrentBar<2)
return....

[NinjaTrader_Lance]

This is because when you add an indicator to a chart it will begin calculating from bar 0 and load each bar in 1 at a time until it reaches the current bar.

Adding the return is beneficial in many scripts that require more data to be loaded before calculating.