Hi Richard - Your upcoming plugin sounds great,
just wondering if it will be 64-bit? With 64-bit computers and
OS's increasingly becoming the norm and 64-bit AmiBroker waiting
in the wings, it would be real nice if
just one maintenance-free data provider could provide a
64-bit API/plugin and remove the 3GB bottleneck for us. And perhaps
get a bunch of new customers...Thank you Sir!
Steve
----- Original Message -----
Sent:
Sunday, January 10, 2010 5:00 AM
Subject:
Re: [amibroker] PremiumData Question
I'll try and explain how this works. It's all a bit
complicated.
There's three "databases" at work:
1. Premium
Data's MetaStock format database
2. AmiBroker's native price
database
3. AmiBroker's security details database
There
are two settings available:
Use Local Data Storage - either Enabled or
Disabled
Data Source - either MetaStock Plug-in or Local
Database.
The default setting is when you set "Use Local data
storage" to false and Data source: MetaStock Plugin. This uses
databases 1 and 3. Database 1 is updated using the Premium Data
program. Database 3 is maintained using the Tools->US-PremiumData
command. Normally Database 2 isn't used, except for composite
symbols you might create.
Why would we want to change
this?
Some people have commented that accessing AmiBroker's native
price database is quicker for large backtests. So how do we copy
data from database1 into database 2? Set "Local data storage" to
Enable and Data source - MetaStock Plugin, then any time you access a
security in database 1, a COPY of the data is placed into database
2. Some people run a scan across all data to popuulate this (eg.
with an entry condition that is always true).
How do we then use
that copied data? Set ""Local data storage" to Enabled and Data source to
Local Database. Note that any updates to database 1 will no longer
be reflected in database 2.
Now, should there be any maintenance
required, you should either change back to the default setting or to the
second setting. Ensure you run Tools->US-PremiumData in this mode
too.
If you decide that maintaining a duplicate of the price data
in Amibroker's natvie price database is too cumbersome, then return the
settings to default as described above. Then shut down
AmiBroker. Make a backup of the entire C:\Program
files\Amibroker\US-PremiumData folder. Delete the A-Z folders
inside the folder C:\Program Files\AmiBroker\US-PremiumData
folder. Start AmiBroker. Click
Tools->US-PremiumData.
What we are doing to improve
this
We are developing a native plugin to AmiBroker and also
getting rid of the MetaStock file format. This should provide
significant performance increases (so there is no need to utilise a native
price database), automatically the database on-the-fly as code/symbol
changes occur (i.e. no need to run Tools-US-PremiumData) plus also
give us extra flexibility to offer new features (such as historical index
constituents - eg. you will be able to specify in your entry conditions
during backtesting "S&P 500 constituent" = true and this will use the
historical set of S&P500 constituents on each relevant day to
determine whether the entry condition is true. This is the ultimate
survivorship-bias-free form of testing.
Best regards,
Richard Dale.
Norgate Investor Services
- Premium quality Stock, Futures and Foreign Exchange Data for
markets in Australia, Asia, Canada, Europe, UK & USA -
www.premiumdata.net
--------
Original Message --------
Subject: [amibroker] PremiumData
Question
From: patsgreatdeals <patsgreatdeals@yahoo.com>
To: amibroker@xxxxxxxxxps.com
Date: Sun, 10
Jan 2010 05:14:24 -0000
I was wondering when using PremiumData.net feed and switching
checking "Use Local Data" so that AMIBroker will run faster with the
data in the AMIBroker Database....
what happens when the
PremiumData downloader renames symbols? I saw a bunch being renamed,
will the AMIBroker DB then have two symbols one with the old name, and
one with the renamed
symbol?