With the exception of the numbered range list, you refer to the variables in a variable list in the same order that SAS uses to keep track of the variables. SAS keeps track of active variables in the order that the compiler encounters them within a DATA step, whether they are read from existing data sets, an external file, or created in the step. In a numbered range list, you can refer to variables that were created in any order, provided that their names have the same prefix.
You can use variable lists in many SAS statements and data set options, including those that define variables. However, they are especially useful after you define all of the variables in your SAS program because they provide a quick way to reference existing groups of data.
Note: Only the numbered range list is used in the RENAME= option.
|Numbered Range Lists|
Numbered range lists require you to have a series of variables with the same name, except for the last character or characters, which are consecutive numbers. For example, the following two lists refer to the same variables:
|Name Range Lists|
|Variable List||Included Variables|
||all variables in order of variable definition, from X to A inclusive|
|x-numeric-a||all numeric variables from X to A inclusive|
|x-character-a||all character variables from X to A inclusive|
You can use the VARNUM option in PROC CONTENTS to print the variables in the order of definition.
/* keeps only the numeric variables idnum, weight, and pulse */ keep idnum-numeric-pulse; /* keeps the consecutive variables name, weight, and pulse */ keep name--pulse;
|Name Prefix Lists|
tells SAS to calculate the sum of all the variables that begin with "SALES," such as SALES_JAN, SALES_FEB, and SALES_MAR.
|Special SAS Name Lists|