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Functional operators – Rockwell Automation 1771-DB BASIC MODULE User Manual

Page 121

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Chapter
Expressions, Variables and Operators

9

9 -11

ATN

Use the ATN operator to return the arctangent of the argument.
The result is in radians. Calculations are carried out to 7 significant digits.
The ATN operator returns a result between +PI/2 (3.1415926/2).

>PRINT ATN(PI)

Result

:

1.2626272

>PRINT ATN(1)

Result:

.78539804

The BASIC module contains a complete set of functional operators.
These operators are single-operand operators.

ABS

Use the ABS operator to return the absolute value of the expression.

>PRINT ABS(5)

Result:

5

>PRINT ABS(-5)

Result:

5

NOT

Use the NOT operator to return the one’s complement of the expression.
The one’s complement is the inverse of the number. BASIC converts the
integer to binary and reverses the state of each bit within the number (ex. it
turns 1s to 0s and 0’s to 1’s). Then BASIC converts the result back into
integer format. The expression must be a valid integer (ex.

between 0

and 65535 (0FFFFH) inclusive

). Non-integers are truncated, not

rounded.

>PRINT NOT(65000)

Result:

535

This example calculates the one’s complement for the number 65000 and
prints the result. First, BASIC converts 65000 to binary:

650000 =1 1 1 1 1 1 0 1 1 1 1 0 1 0 0 0

Then the BASIC module replaces the 1’s with 0’s and the 0’s with 1s.

1 1 1 1 1 1 0 1 1 1 1 0 1 0 0 0
0 0 0 0 0 0 1 0 0 0 0 1 0 1 1 1

BASIC converts the resulting binary number back into an integer and
prints the result.

0 0 0 0 0 0 1 0 0 0 0 1 0 1 1 1 = 535

Functional Operators