Rockwell Automation 2098-IPD-xxx Ultra5000 C Programming using the Motion Library User Manual
Page 32

Publication 2098-PM001E-EN-P — July 2002
1-20
Programming Motion Control in C
lists the precedence and describes the functions and any limitations
placed on the arithmetic operations in C.
Operator:
Precedence:
Function:
Limitations:
*
1
Multiplies the value on its
right by the value on its
left.
/
Divides the value at its left
by the value on its right.
Answer is truncated if
both operands are
integer or long.
%
Yields the remainder when
the value at its left is
divided by the value to it
right.
Integer or long
++
2
In the prefix mode, adds 1
to the value of the variable
to its right, before the value
is used.
In the suffix mode, adds 1
to the value of the variable
to its left, after the value
was used.
If n is 5, then x = ++n
sets x to 6, but x = n++
sets x to 5.
(incrementing n after
its value is used). In
both cases
n
becomes
6
).
--
In the prefix mode,
subtracts 1 from the value
of the variable to its right.
In the suffix mode,
subtracts 1 from the value
of the variable to its left.
If n is 5, then x = --n
sets x to 4, but x = n--
leaves x at 5
(decrements n after its
value is used). In both
cases
n
becomes 4).
+
(unary form)
3
Changes the sign of the
value on its right.
-
(unary form)
Changes the sign of the
value on its right.
+
(binary form)
4
Adds the value at its right
to the value at its left.
-
(binary form)
Subtracts the value at its
right from the value at its
left.