Multiple instrument out of range

[FireFly]

Suppose I make an indicator where I simply plot the close of a second instrument as an indicator. This is of course easy to do with:

Add( <instrument>, PeriodType.Day, 1 );

and

protected override void OnBarUpdate()
{
plot0.Set(Closes[1][0]);
}

This works fine until I select a range on my chart where the primary instrument doesn't have any data. For example, if I have data for MSFT from 1/1/1990 and IBM from 1/1/1980. I use MSFT as my primary instrument and I plot IBM as an indicator using the method above. As long as I don't choose an earlier startdate than 1/1/1990 for my chart there is no problem. However if I choose for example 1/1/1989 as startdate I get an error message: "You are accessing an index with a value that is invalid since its out of range".

If I have only the primary instrument on my chart without the indicator then there is no problem. Even if I select the chart to start on 1/1/1989, it will simply start from 1/1/1990 because it has no earlier data. However when using the indicator based on a second instrument it gives an error. It apparently gets an invalid index.

How can I prevent this from happening in my code? I want to make it robust, so maybe I need to somehow check if the primary series exists before doing plot0.Set(Closes[1][0])? How can I do that?

[NinjaTrader_Bertrand]

FireFly, please try including a CurrentBars check for all involved series - for example :

if (CurrentBars[0] <= BarsRequired || CurrentBars[1] <= BarsRequired)
return;

[FireFly]

@NinjaTrader_Bertrand: that doesn't solve the problem.

BUT it seems I have already solved the problem by simply using

if (BarsInProgress == 0)
{

}

How stupid that I didn't think about that earlier!