WTI PollCat NetLink, Руководство пользователя

Страница: 230 / 256

E.1.1. The Comparative Operators
When the comparative operators ( > , < , >= , and <= ) are used, care
must be taken to limit the scope of the comparison.
When NetLink compares information in a call record with values
indicated in the clue definition, it performs an "ASCII
comparison". All ASCII characters are compared, not just
numbers. Each ASCII character, (including letters and symbols)
has a numerical value. Letters of the alphabet have a higher value
than numbers, and symbols have a lower value.
Although call records may always have a numerical value in a
specific field, "non-data" such as headers and summaries, might
have letters or symbols in that field. When creating an Alarm Clue
that includes the comparative operators, NetLink must be
prevented from counting symbols and alphabetic characters as
numerical values.
For example, if the variable "B" represents call duration and you
wish to check for calls lasting longer than 15 minutes, the
definition would include the phrase "B>15:00". Unfortunately, this
would also count headers that have alphabetic text in the call
duration field.
If your Alarm Clues are also counting non-data, the techniques
described in the following sections can be used to obtain a more
reliable count.
E.1.1.1. Limit Comparisons
When comparative operators are used, values can be defined as a
range between two numbers, rather than an open ended range. In
other words, if a "Greater Than" operator is used, it can be
matched with a "Less Than" operator in order to limit the scope of
the comparison.
Example: Define a clue that counts calls placed after 5:00 pm
(17:00). Assume that the variable "A" represents the time the call
was placed. The most direct way to define match parameters is as
follows:
A>17:00
Apx-8
PollCat NetLink User's Guide