Suppose you have a list of variables. You don’t want to type the name of each variable every time to define them within the function or array. You are looking for a shortcut to accomplish this task.
Create a dataset with a list of variables
data dummy; input a1 a3 a4 a2 a6$ bs$ a5; cards; 2 1 3 5 aa xy 2 2 5 4 1 ab xz 4 2 7 3 9 ac wx 3 ; run; |
How to specify a list of variables
A single dash (-) refers to specify consecutive numbered variables. For example: a1-a4;
A double dash (–) refers to specify variables based on the order of the variables as they appear/entered in the file, regardless of the name of the variables.
data dummy1 ( drop = a1 --a5); set dummy; sum = sum ( of a1-a4); sum1 = sum ( of a1 --a4); run; |
In the above program, a1-a4 includes a1, a2, a3 and a4, whereas a1--a4 includes a1, a3 and a4 only as they appear the same way in file.
How to specify all NUMERIC variables
data dummy1 ( drop = a1 --a5); set dummy; sum = sum ( of _numeric_); run; |
How to use double dash in array
The below-defined program will subtract one from values in variables a1, a3 and a4.
data dummy1; set dummy; array vars a1 --a4; do over vars; vars = vars - 1; end ; run; |
How to use numeric variables in array
The below-defined program will subtract one from values in numeric variables.
data dummy1; set dummy; array vars _numeric_; do over vars; vars = vars - 1; end ; run; |