OnMarketData VS OnBarUpdate

[Ramon]

Is there any difference between using OnBarUpdate

CalculateOnBarClose = False
..
last=Close[0];
bid = GetCurrentBid();
ask=GetCurrentAsk();

... and OnMarketData

if ( marketDataType.Last) last = e.Price
if ( marketDataType.Bid) bid = e.Price
if ( marketDataType.Ask) ask = e.Price

(Don't try to compile this at home)

[NinjaTrader_Joydeep]

Hello Ramon,
Thanks for writing in and I am happy to assist you.

NinjaTrader being multi-threaded with OnMarketData and OnBarUpdate being called in their own respective thread, there can be difference between GetCurrentAsk() and e.Price as ask price derived from OnMarketData.

Please let me know if I can assist you any further.

[Ramon]

I supposed, however the latest crossed price should match in both methods . is it so? . I mean
(last) e.Price == Close[0]

or not?

[NinjaTrader_Joydeep]

Hello Ramon,
It may or may not match since Close and e.Price are updated on different thread.

Please let me know if I can assist you any further.

[Ramon]

In times of Livermore, Mr. Investor bought a contract to 890.25 and the tape recorded this fact

Today Mr Investor Jr. buys a contract to 1342.75 and thanks to technology this fact depends on whether you use OBU or OMD.
I do not think that the fact that Livermore shot himself in the head has nothing to do with the progress of computers.

So , we better continue using OMD to record events in Level 1 (Time & Sales) ?

[NinjaTrader_Joydeep]

Hello Ramon,
OnMarketData and OnBarUpdate has its own pros and cons. We provide you options, and it depends on your exact requirement, on how you utilize it to its optimum.

Please let me know if I can assist you any further.