SAS Not In – How to Check if Variable is Not in List of Values

To check if a variable’s value is not in a list of values, we can use the SAS not operator in combination with the in operator.

data k;
    a = 4;
    if a NOT IN (1, 2, 3) then put 'a is not in (1, 2, 3)';
run;

/* Output: */
 a is not in (1, 2, 3)

When working in SAS, logical operators allow us to control the flow of our data.

There are many different logical operators which allow us to perform checks on the values of the variables we are working with.

One such check is to see if a variable is in or not in a list of values.

If you want to check against a collection of values, you can use the SAS not operator in combination with the in operator.

not in checks if the variable is not equal to each of the values of your array.

Below is an example of how to use not in in a SAS data step to see if a variable value is not in a list of values.

data k;
    a = 4;
    if a NOT IN (1, 2, 3) then put 'a is not in (1, 2, 3)';
run;

/* Output: */
 a is not in (1, 2, 3)

Checking to See if a Value is IN a List of Values in SAS

If you want to check if a value is in a list of a values in SAS, you can use the in operator. The in operator used in a SAS data step is very useful when you want to see if a variable is in an array of values.

Let’s say we have following data set which we create with the following data step:

data k;
    input animal_type $ gender $ weight age state $ trained $;
    datalines;
    cat  male     10    1    CA     no
    dog  male     20    4    FL     no
    dog  male     30    5    NY     no
    cat  female   40    3    FL     yes
    cat  female   10    2    NY     yes
    dog  female   20    4    TX     yes
    cat  female   50    6    TX     yes
    dog  male     60    1    CA     no
    dog  male     70    5    NY     no
    cat  female   80    4    FL     yes
    cat  female   90    3    TX     yes
    cat  male     100   2    TX     no
    dog  female   80    4    FL     no
    ;
run;

Let’s create another variable “Region” by using the IN operator. Let’s say that if state is Texas (“TX”) or Florida (“FL”) that “Region is “South” and if it’s not, then “Region” is “Other”.

We can easily do this with the following SAS code:

data m;
	set k;
	if state in ("TX", "FL") then region = "South";
	else region = "Other";
run;

The resulting SAS data set will look like the following: