SAS array

Arrays in SAS are used to store and retrieve a series of values using index values. T he index represents the location in the reserved store.

Syntactic

In SAS, arrays are declared using the following syntax:

ARRAY ARRAY-NAME(SUBSCRIPT) ($) VARIABLE-LIST ARRAY-VALUES

In the syntax above:

• ARRAY is the SAS keyword that declares an array.
• ARRAY-NAME is the name of an array that follows the same rules as the variable name.
• SUBSCRIPT is the number of values that an array wants to store.
• ($) is an optional parameter that is used only when the array wants to store character values.
• VARIABLE-LIST is an optional list of variables, which are placeholders for array values.
• ARRAY-VALUES is the actual value stored in the array. T hey can be declared here, or they can be read from a file or dataline.

An example of an array declaration

Arrays can be declared in a variety of ways using the above syntax. H ere's an example.

# Declare an array of length 5 named AGE with values.
ARRAY AGE[5] (12 18 5 62 44);

# Declare an array of length 5 named COUNTRIES with values starting at index 0.
ARRAY COUNTRIES(0:8) A B C D E F G H I;

# Declare an array of length 5 named QUESTS which contain character values.
ARRAY QUESTS(1:5) $ Q1-Q5;

# Declare an array of required length as per the number of values supplied.
ARRAY ANSWER(*) A1-A100;

Access array values

The values stored in the array can be accessed by using the printing process shown below. A fter declaring using one of the above methods, datalineS statements are used to provide data.

DATA array_example;
INPUT a1 $ a2 $ a3 $ a4 $ a5 $;
ARRAY colours(5) $ a1-a5;
mix = a1||'+'||a2;
DATALINES;
yello pink orange green blue
;
RUN;
PROC PRINT DATA=array_example;
RUN;

When we execute the code above, it produces the following results:

Use the OF operator

The OF operator is used when analyzing arrays in the form of arrays to perform calculations on the entire row of the array. I n the following example, we apply the and equal values of the values in each row.

DATA array_example_OF;
	INPUT A1 A2 A3 A4;
	ARRAY A(4) A1-A4;
	A_SUM=SUM(OF A(*));
	A_MEAN=MEAN(OF A(*));
	A_MIN=MIN(OF A(*));
	DATALINES;
	21 4 52 11
	96 25 42 6
	;
	RUN;
	PROC PRINT DATA=array_example_OF;
	RUN;

When we execute the code above, it produces the following results:

Use the IN operator

You can also use the IN operator to access the values in the array, which checks for the presence of values in the array row. I n the following example, we examine the availability of the color "yellow" in the data. T his value is case sensitive.

DATA array_in_example;
	INPUT A1 $ A2 $ A3 $ A4 $;
	ARRAY COLOURS(4) A1-A4;
	IF 'yellow' IN COLOURS THEN available='Yes';ELSE available='No';
	DATALINES;
	Orange pink violet yellow
	;
	RUN;
	PROC PRINT DATA=array_in_example;
	RUN;

When we execute the code above, it produces the following results: