SAS - Strings

Strings in SAS are the values which are enclosed with in a pair of single quotes. Also the string variables are declared by adding a space and $ sign at the end of the variable declaration. SAS has many powerful functions to analyze and manipulate strings.

Declaring String Variables

We can declare the string variables and their values as shown below. In the code below we declare two character variables of lengths 6 and 5. The LENGTH keyword is used for declaring variables without creating multiple observations.

data string_examples;
   LENGTH string1 $ 6 String2 $ 5;
   /*String variables of length 6 and 5 */
   String1 = 'Hello';
   String2 = 'World';
   Joined_strings =  String1 ||String2 ;
run;
proc print data = string_examples noobs;
run;

On running the above code we get the output which shows the variable names and their values.

String Functions

Below are the examples of some SAS functions which are used frequently.

SUBSTRN

This function extracts a substring using the start and end positions. In case of no end position is mentioned it extracts all the characters till end of the string.

Syntax

SUBSTRN('stringval',p1,p2)

Following is the description of the parameters used −

• stringval is the value of the string variable.
• p1 is the start position of extraction.
• p2 is the final position of extraction.

Example

data string_examples;
   LENGTH string1 $ 6 ;
   String1 = 'Hello';
   sub_string1 = substrn(String1,2,4) ;
   /*Extract from position 2 to 4 */
   sub_string2 = substrn(String1,3) ;
   /*Extract from position 3 onwards */
run;
proc print data = string_examples noobs;
run;

On running the above code we get the output which shows the result of substrn function.

TRIMN

This function removes the trailing space form a string.

Syntax

TRIMN('stringval')

Following is the description of the parameters used −

• stringval is the value of the string variable.

data string_examples;
   LENGTH string1 $ 7  ;
   String1='Hello  ';
   length_string1 = lengthc(String1);
   length_trimmed_string = lengthc(TRIMN(String1));
run;
proc print data = string_examples noobs;
run;

On running the above code we get the output which shows the result of TRIMN function.