Campbell Scientific PC400 Datalogger Support Software - Manual (Page 144)

Section 8. Datalogger Program Creation with Edlog
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 8-1 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 ( _ ).
TABLE 8-1. Operators and Functions
Operators
* multiply
/ divide
+ add
- subtract
^
raise to the power of; enclose negative values in parentheses
@ modulo divide
E scientific notation; 6e-1=0.6
Functions
COS
cosine; angle in degrees
SIN sine; angle in degrees
TAN tangent; angle in degrees
COTAN cotangent; angle in degrees
ARCTAN arctangent; angle in degrees
ARCSIN arcsine; angle in degrees
ARCCOS arccosine; angle in degrees
ARCCOT arccotangent; angle in degrees
SQRT square root
LN natural logarithm
EXP exponent of e; EXP(2) = e 2
RCP reciprocal; RCP(4) = 1/4 = 0.25
ABS absolute value
FRAC takes the fraction portion; FRAC(2.78)=.78
INT takes the integer portion; INT(2.78)=2
8-8