OnMarketData() vs. OnBarUpdate()

[Tight Face]

I am trying to understand how one of these methods would fire where the other does not.

1.What event can happen for OnBarUpdate to trigger, where it does not trigger OnMarketData?

2. Same question, for OnBarUpdate?

...

I might assume for example that, someone withdrew their pending inside bid (causing the inside bid volume to drop), which would trigger an OnMarketData() call, but no change in OnBarUpdate(). Correct?

I might also assume that any tick update in OnBarUpdate() will also result in an OnMarketData() call (since it ultimately results in a change in either inside bid or inside ask volume, OnMarketData territory). Is this correct?

[NinjaTrader_JoshP]

1. If you have CalculateBarOnClose, OnBarUpdate() will not fire every tick while OnMarketData() will.

2. The same goes for OnMarketDepth().

OnMarketData() is essentially level 1 data. OnMarketDepth() is level 2 data so you can build your own bid/ask price ladders with OnMarketDepth() which can be seen here: http://www.ninjatrader-support.com/v...ead.php?t=3478

OnMarketDepth() will change for every bid/ask change while OnBarUpdate() basically just last price.

[Tight Face]

Hi Josh,

Understand... But if CalculateBarOnClose = false, then how does OnMarketData() differ from OnBarUpdate()?

[NinjaTrader_JoshP]

Essentially doesn't.

[NinjaTrader_Ray]

OnBarUpdate() fires when an update to the Bar occurs which of course is driven by a last trade event. OnMarketData fires on the last trade event among other events. OnBarUpdate() you get the time of bar, OnMarketData() you get the time of the actual market data event.

[Tight Face]

OK great. This is info that I did not find in the helpful manual. Can you elaborate a little on "among other events"?

Thanks

[NinjaTrader_Ray]

other events - Changes in daily high, low, open, close, bid, ask price and volume