Insider TA: Data Merger Basics
The Data Merger functionality dates back over 15 years to the earliest version of Insider TA. Considered a great feature back then, its value has steadily diminished over the years, particularly in light of the wonderful ASCII downloaders that perform the same functions and more! We're pondering removing the Data Merger feature altogether in future Insider TA versions.
The Data Merger utility provides Insider TA the ability to automatically
update your entire portfolio of ASCII stock files with new data, either
on a weekly or daily basis. The examples that follow illustrate updating
You will need to download from your favorite source a listing of end-of-day
price information (Date, Open, High, Low, Volume, etc.) for your portfolio
of stocks. Such listings are text-based files that we refer to
as recap files, because they provide a recap of your
portfolio's trading data.
The following figure illustrates how the Data Merger takes the data from
a generic recap file, and updates each of your stock files:
Note in the above figure how the destination files do not necessarily
have to follow a specific field order. In our illustration shown above:
- The first is comma-delimited and has TICKER, FREQ, DATE, HIGH, LOW,
LAST, and VOLUME on each line.
- The second is comma-delimited and has DATE, HIGH, LOW, and VOLUME
on each line.
- The third is space-delimited and has HIGH, LOW, and VOLUME on each
We show these variations to illustrate how the Data Merger is
not limited to working with any specific field order. In fact, each stock
file in your portfolio can have its own unique configuration.
The Data Merger's Portfolio List
How does Insider TA know which stock file to append data to? That
is the responsibility of the Data Merger's Portfolio List...
Portfolio List Window
Note in the above illustration how every stock symbol is associated with
its own data file.
If a target datafile is not associated with a symbol, then Insider
TA selects a filename with a "TXT" extension and saves it
to its own "\ASCII" subdirectory. The above figure illustrates
This auto-naming convention is handy for those cases where you already
have a long list of symbols, and you don't want to spend a lot of time
manually entering filenames for each symbol. Simply append your list file
to the PORTFLIO.LST file (using any text editor), and Insider TA
will automatically create "TXT" files in its \ASCII directory.
The name of the recap file is not entered into the Portfolio List Window, but
rather the field labeled "File(s) to Process" in the Data Merger Window.
Requirements of "Recap Files"
The structure of recap files must follow some basic guidelines.
Insider TA's Data Merger requires the following:
- Recap files must be ASCII (simple text) format.
- All data for a given stock must be on the same line. At a minimum,
the high and low price, volume and ticker symbol must be included. The
order of data items can be in any format, but must be consistent for
all data lines in the file
- Price values can exist in decimal or fractional format. For example,
$1.75 can be represented as "1-3/4" or "1 3/4".
In the latter case, only a single space can separate the whole part
from the fraction part of the price value.
- The file does not necessarily have to consist exclusively of data
lines. When supplied with the necessary information, INSIDER TA
will know which lines contain data and which do not.