Campbell CR5000, Руководство оператора

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8-1
Section 8. Processing and Math
Instructions
Operators
^ Raise to Power
* Multiply
/ Divide
+ Add
- Subtract
= Equals
<> Not Equal
> Greater Than
< Less Than
>= Greater Than or Equal
<= Less Than or Equal
ABS (Source)
Returns the absolute value of a number.
Syntax
x = ABS (source)
Remarks
Source can be any valid numeric expression. The absolute value of a number
is its unsigned magnitude. For example, ABS(-1) and ABS(1) both return 1.
ABS Function Example
The example finds the approximate value for a cube root. It uses Abs to
determine the absolute difference between two numbers.
Dim Precision, Value, X, X1, X2 'Declare variables.
Precision = .00000000000001
Value = Volt(3)
'Volt(3) will be evaluated.
X1 = 0: X2 = Value 'Make first two guesses.
'Loop until difference between guesses is less than precision.
Do Until Abs(X1 - X2) < Precision
X = (X1 + X2) / 2
If X * X * X - Value < 0 Then
'Adjust guesses.
X1 = X
Else
X2 = X
End If
Loop
'X is now the cube root of Volt(3).