Campbell LoggerNet, Инструкция по эксплуатации

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Section 7. Creating and Editing Datalogger Programs
7.4.2.6 Expressions
Algebraic expressions can be used in a program to easily perform processing
on input locations. When a datalogger program that contains an expression is
compiled, the appropriate instructions are automatically incorporated into the
DLD file. As an example, the following expression could be used to convert
temperature in degrees Celsius to temperatures in degrees Fahrenheit:
TempF=TempC*1.8+32
Following are rules for creating expressions:
•
Expressions must be set equal to the label of the Input Location that will
store the result. The result label must be to the left of the expression.
•
Expressions can have both fixed numbers and Input Location labels. Input
Locations can only be referenced by their label; each number in an expression
is assumed to be a constant.
•
Floating-point numbers are limited to six digits plus the decimal point and
sign.
•
The operator(s) and/or function(s) used in the expression are limited to
those in the Operator and Function list (TABLE 7-5 below).
•
Numbers and labels that appear immediately after a function must be
enclosed in parentheses.
•
Several operators and/or functions can be used in one expression.
Operations and functions that are enclosed in parentheses are calculated
first; the innermost parentheses are evaluated first.
•
To continue an expression to the next line, end the first line with an
underscore ( _ ).
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