Download SAS--Operators

UNC-Wilmington
Department of Economics and Finance
ECN 377
Dr. Chris Dumas
Mathematical and Logical Operators in SAS
(TIP: For more info, when in SAS go to SAS Help, click on Index tab, and search using
keywords “Expressions” and “Functions”.)
A SAS operator is a symbol that represents a comparison, arithmetic calculation, or logical
operation; a SAS function; or grouping parentheses.
Arithmetic Operators
Symbol
Definition
Example
**
exponentiation
a**3
*
multiplication
2*y
Result
raise A to the third
power
multiply 2 by the
value of Y
/
division
var/5
divide the value of
VAR by 5
+
addition
num+3
add 3 to the value of
NUM
-
subtraction
sale-discount
subtract the value of
DISCOUNT from
the value of SALE

NOTE 1: The asterisk (*) is always necessary to indicate multiplication; 2Y and 2(Y) are
not valid expressions.

NOTE 2: If a missing value is an operand for an arithmetic operator, the result is a
missing value. So, if you tell SAS to calculate y = a*X, and either “a” or “X” is a
missing value, then “y” will be a missing value.
The LOG and LOG10 Operators
The operator “LOG” performs natural logarithms, and the operator “LOG10” performs base 10
logarithms. For example,
lnGNP = LOG(GNP);
creates a new variable named lnGNP by taking the natural log of variable GNP.
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Comparison Operators
Symbol
Mnemonic
Equivalent
Definition
Example
=
EQ
equal to
a=3
a EQ 3
^=
NE
not equal to
a ^= 3
a NE 3
¬=
NE
not equal to
a ¬= 3
~=
NE
not equal to
a ~= 3
>
GT
greater than
a>5
<
LT
less than
a<8
>=
GE
greater than or equal to
a>=300
<=
LE
less than or equal to
(no symbol for this
one)
IN
equal to one of the
items in a list
a<=100
A LE 100
a IN (3, 4, 5)

NOTE: You can use either the math symbols or the mnemonic equivalents (or both) when
writing equations in SAS.

NOTE: Comparison operators appear frequently in IF-THEN statements, as in this
example:
if x<y then c=5;
if x LT y then c EQ 5;
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Logical Operators
Logical operators, also called Boolean operators, are usually used in expressions to link
sequences of comparisons. The logical operators are shown in the following table:
Symbol
Mnemonic Equivalent
Example
&
AND
(a>b & c>d)
|
OR
(a>b or c>d)
!
OR
¦
OR
¬
NOT
ˆ
NOT
~
NOT

not(a>b)
NOTE: Notice in the table above that there are several, alternative symbols that you
could use for “OR” or “NOT.” The symbol that you should use for OR or NOT depends
on your “operating environment” (the particular keyboard and operating system software
that you are using).
The MIN and MAX Operators
The MIN and MAX operators are used to find the minimum or maximum value of two
quantities.
MIN
><
MAX
<>
MIN operator Surround the operators with the two quantities whose minimum or maximum
value you want to know. The MIN operator, " >< ", returns the lower of the two values. The
MAX operator, " <> ", operator returns the higher of the two values.
For example, the command “y = a><b;” would set y equal to the smaller of a or b.
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