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Investor/RT
Tutorials
Using Scans in Investor/RT
This Tutorial will be helpful in the following
areas...
- Creating Scans
- Understanding Scan Logic
- Using Comparative Operators in
Scans (>, <, =,etc.)
- Using Arithmetic Operators in
Scans (+, *, %, etc.)
- Proper Parenthesizing in Scans
- Qualifying Scan Tokens
- Compound Expressions in Scans
- Setting Data Values with Scans
- Renaming Scan Tokens
- Automated Scanning
For additional information on Scans, also see Scans
Tour. Scans were originally developed to scan a list of
securities in search of a given signal or pattern. As our scanning
language has grown, the functionality of scans has broadened tremendously. Scans
can now be used to set data column values, alter the properties of instruments,
and much more. Scans have become extremely powerful. This
tutorial was written to help users harness this power for themselves.
Let's start by looking at the Scan window and
identifying the main components. The scan window can be accessed in
three ways. From the main menu, you can choose "File: New:
Scan", from the main toolbar, you can click on the "Open
Scan" button, or you can choose "Open: Scan" from the main
menu to open an existing scan. Below is a scan window containing a
MACD Bullish scan.

The colored letters are used to identify the main
components, which are described in further detail below...
- A - This is a
drop down list box containing all the previously saved scans.
When you select a scan in this list, the remainder of the window
reacts by filling in the scans definition (periodicity, scan
expression, quotepage, etc.). The first choice in this list is
"New Scan Definition". Choose this option if you would
like to create a new scan.
- B - This is a
periodicity selection control. Here you choose the timeframe of
the data on which your scan will run. In other words, you are
choosing the time per bar for the scans input data. For instance, you may
choose to run your scan on daily data, 5 minute bars, 1 minute bars,
etc.
- C - This is
the list of available scan tokens. Each entry in the list shows
the scan token, followed by a colon, followed by a short description
of the token. The scan token is what is used in forming scan
expressions. For a complete list of scan tokens, click here.
- D
- This is a list of the tokens that are being used (or are to be used)
in the current scan. This is a spreadsheet style control, with
columns for Token, Name, and Preferences. As you will see later,
some tokens have preferences and some do not. For example,
Moving Average (MA) would have preferences like Period and Type, while
Closing Price (CL) would have no additional preferences. The
Name column is editable. We will discover later why it is useful
to be able to rename your tokens once you've added them to this list.
- E
- This is the box that contains the actual scan expression (also
referred to as scan equation or scan syntax). Ultimately, this
expression should result in a TRUE of FALSE value. For
instance, the expression in the scan above is "MACD1 < 0 AND
MACD >= 0". The scan will run on a list of
instruments specified by your choice of quotepages. For each
instrument, it will evaluate the expression above. If the MACD
of the previous period (or bar) is less than zero while the MACD of
the current period is greater than zero (in essence, a bullish MACD
crossover), then the expression results in TRUE for that
instrument. The result of the scan will be a QuotePage
containing all instruments for which the scan expression resulted as
TRUE. The QuotePage will show the ticker symbols, along with the
values used in determining the scan expression. This will all
become more clear as we work through some examples on the following
pages.
- Buttons and Lists - There
are several buttons and lists along the base of the window.
The "QP" List allows you to choose the input QuotePage for the scan, or
essentially which list of instruments you would like to run the scan
on.
The "Format" List allows you to specify a specific quotepage
format for the resulting quotepage.
The "Bars" List allows you to
specify how many bars will be loaded during evaluation of the
expression. The most common setting is "Automatic" which instructs
Investor/RT to compute the minimal amount of bars needed to compute the
desired result.
The "Check" button checks the
scan for valid syntax. If you hold down the Ctrl key while clicking
on the Check button, a window will pop up showing you the order of
evaluation of your expression. This will help ensure your
expression is being evaluated in the proper order.
The "Export" button exports
the scan to a text file which can be used to share the scan with other
users.
The "Setup..." button gives
the users various options for what to do if scan criteria are met, as
well as a shortcut for quickly creating a schedule that involves the
scan.
The "Save" button saves your
scan. If you haven't already given your scan a name, it will ask
you for one.
The "Save As" button If you have already given
your scan a name and would like
to save it under a different name, simply click this button.
This is commonly used to "duplicate" an existing scan, or use one as a
"template".
The "Scan" button executes or
runs the scan.
Let's start by looking at a very basic scan....
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