Campbell Scientific LoggerNet Datalogger Support Software - Manual (Page 345)

Section 8. Working with Data Files on the PC
Logical “and” and “or” statements can be used when specifying the Start
Condition. A logical “and” statement means that all conditions must be true
for the statement to be true. Up to three conditions can be connected with
“and” statements. If too many “and” statements are used, an error message will
be displayed when you run Split.
The logical “or” statement means that if any of the conditions are true, then the
statement is true. Split allows up to six conditions to be connected with “or”
statements. Additionally, each “or” statement can contain up to three “and”
conditions. As with the “and” statements, if the maximum number of valid
statements is exceeded, an error message will be displayed.
These rules for logical statements also apply to the Stop and Copy Conditions.
An example of a simple logical “and” statement follows:
2[189]and3[1200]
Element two (the Julian day) must equal 189, and element three (the time in
hours/minutes) must equal 1200.
If the following “and” statement was used:
2[189]and3[1200]and4[92]and5[67]
an error would be returned because the maximum number of allowable “and”
statements has been exceeded.
A range can be specified for val
i
by putting “..” between the lower and upper
limit. For example:
2[189]and7[200..275]
In this example two conditions must be satisfied to start processing data. First,
the day of year must be 189, and second, element 7 must be between 200 to
275 degrees, inclusive.
8.2.3.1.3.1 Starting Relative to PC Time
Split has the ability to start relative to the current PC TIME (computer time).
This feature allows a .PAR file to be run on new data files without changing
the Start Conditions, provided the Input Data File is collected at a fixed interval
and Split is run at a fixed interval. For example, the same PAR file could be
run every day to display the last 48 hours of data without changing the start
conditions. For example, using a table based data file:
Start Condition = 1:1[–1]:1[1200]:1:
In this instance, Split will begin processing data when the date for both files is
one less than the current date (1: 1[–1]:1[1200]:1:)and the time is 1200 (1:1[–
1]: 1[1200]:1:).
As an expanded example, assume that LoggerNet is used to append data to an
archive file. SplitR is executed using a desktop shortcut. In this case the
frequency of data collection and data reduction is the same. Time values in the
data file (day, hrmn, sec.) are different each time the data are collected, but by
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