Raritan Computer Home Security System - Manual (Page 70)

Chapter 6: Devices, Device Groups, and Ports
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ƒ & - the AND operator. A node must satisfy rules on both sides of
this operator for the description (or that section of a description)
to be evaluated as true.
ƒ | - the OR operator. A device needs to satisfy only one rule on
either side of this operator for the description (or that section of a
description) to be evaluated as true.
ƒ ( and ) - grouping operators. This breaks the description into a
subsection contained within the parentheses. The section within
the parentheses is evaluated before the rest of the description is
compared to the node. Parenthetical groups can be nested
inside other parenthetical groups.
Example1: If you want to describe devices that belong to the
engineering department, create a rule that says Department =
Engineering. This will become Rule0. Type Rule0 in the Short
Expression field.
Example 2: If you want to describe a group of devices that belong
to the engineering department or are located in Philadelphia, and
specify that all of the machines must have 1 GB of memory, you
must create three rules. Department = Engineering (Rule0)
Location = Philadelphia (Rule1) Memory = 1GB (Rule2).These
rules must be arranged in relation to each other. Since the device
can either belong to the engineering department or be located in
Philadelphia, use the OR operator, |, to join the two: Rule0 |
Rule1. Make this comparison first by enclosing it parentheses:
(Rule0 | Rule1). Since the devices must both satisfy this
comparison AND contain 1GB of memory, use the AND
connector, &, to join this section with Rule2: (Rule0 | Rule1) &
Rule2. Type this final expression in the Short Expression field.
Note: You should have a space before and after operators & and |.
Otherwise, the Short Expression field may return to the default
expression, that is, Rule0 & Rule1 & Rule2 and so on, when you
delete any rule from the table.
ƒ To remove a row from the table, select the row, and then click the
Remove Row icon .
ƒ To see the list of devices whose parameters follow the rules you
have defined, click View Devices.
6. Click Validate when a description has been written in the Short
Expression field. If the description is formed incorrectly, you will
receive a warning. If the description is formed correctly, a normalized
form of the expression appears in the Normalized Expression field.