Joe, when I tested the IQFeed plugin 1.60 in January, I always set up fresh databases and of course with base interval daily. I also installed the new IQFeed client 4.1.0.0.
Here is my initial report on this mailing list, although I sent addition comments to Amibroker support later: http://finance.groups.yahoo.com/group/amibroker/message/92835 The problem I encountered was as follows: Initially backfill worked well in daily mode. But when trying to backfill data for all symbols in the Amibroker database, using Amibroker's auto analysis feature with "wait for backfill" set to true, the problem occurred. Then the state of the plugin somehow got corrupted. For example, after selecting a specific symbol, let's say "msft", where backfill worked fine initially (or on a standalone basis), Amibroker set the title of the chart window correctly to msft. But in the chart it suddenly displayed data for a different ticker symbol I had in my database instead of the data for msft. In my specific case, the data shown in the chart was apparently for one of the market breath indicators such as IINA.Z, one of the other symbols I had in my database. More precisely, the last (= right-most/most recent) bar was always correct, but all the previous backfilled bars were clearly for one of the other ticker symbols I had in my database. This same erroneous behavior happened with many other stocks too once the plugin state got corrupted. To get back to the msft example: initially backfill could have worked perfectly for a given symbol such as msft so that the correct data was displayed. But once the plugin state got corrupted, the plugin was returning the wrong history to Amibroker (with the exception of the right-most bar). This is important to note because if backfill for a symbol like msft is working fine, it could still be the case that the plugin state gets corrupted so that at a later point of time data for a different symbol is displayed by Amibroker. When I reported the bug in late January, I assumed the problem might be triggered by attempts to backfill invalid or expired symbols in the database. For example, tickers such as "@YIF5" (CBOT mini sized silver future January 2005, ie. this contract was already expired in January of this year). Or even fantasy symbols that don't exist such as ABCDE. However, even though I was almost always able to get the state of the plugin corrupted when using backfill for a large list of tickers in auto analysis mode, I was NOT able to exactly confirm that invalid/expired symbols were the "culprit". It could be a different reason. For example, the plugin could possibly use some hash table or collection data structure to associate ticker symbols with histories. These associations might somehow get corrupted so that, when requesting the history for a given ticker, the data for a different symbol of the database is erroneously returned. But from my perspective, without log messages it's difficult if not impossible to identify the exact reason. Only TJ could do it. Back in January I sent to Amibroker support a list of test symbols with a script to import them into the Amibroker database. From Marcin Gorzynski I received the reply that he observed similar problems during his initial tests. Btw: How many tickers are you backfilling in daily mode, Joe? Just two (QQQQ and SPY) or really a longer list of symbols (for example, 200 symbols). For testing testing purposes also the backfill of invalid and expired tickers would be interesting. --- In [email protected], Joe Maywood <[EMAIL PROTECTED]> wrote: > > tech917, > > Thursday, March 30, 2006, 3:36:56 PM, you wrote: > > > I know you're working hard on Amibroker 4.80, but speaking of IQFeed: > > Any comment on the IQFeed plugin 1.60 in daily mode? > > Running an IQFeed trial here on AB 4.79.0, IQ Plugin 1.6.0 and latest > DTNiq / IQFeed client. Using AB local data, EOD base interval and > checking both QQQQ and SPY symbols, data goes back to 12/2003. Are you > per chance using an intraday base interval for the database? Their > service level states 120 days for interval data? > > My disappointment with the AB IQFeed support is the lack of tick data > backfill support by the (1.6.0) plugin. Hopefully Tomasz will get it > updated soon. > > -- > Best regards, > Joe > ------------------------ Yahoo! Groups Sponsor --------------------~--> Try Online Currency Trading with GFT. Free 50K Demo. Trade 24 Hours. Commission-Free. http://us.click.yahoo.com/RvFikB/9M2KAA/U1CZAA/GHeqlB/TM --------------------------------------------------------------------~-> Please note that this group is for discussion between users only. To get support from AmiBroker please send an e-mail directly to SUPPORT {at} amibroker.com For other support material please check also: http://www.amibroker.com/support.html Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/amibroker/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
