Campbell CR9000, Инструкция по эксплуатации

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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
Absolute Value
Returns the absolute value of a number.
Syntax
Abs(
number
)
Remarks
The argument number 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).