How should a variable list be utilized in a function in SAS?

Utilizing a variable list in a function in SAS is effectively done by using the "of" keyword before the variable names when working with certain functions. This is particularly useful when applying functions such as SUM, MEAN, or other statistical calculations across multiple variables. The "of" statement helps in specifying that the function should consider a list of variables together.

For example, in a DATA step, if you have several numeric variables (e.g., var1, var2, var3), you can calculate their sum using the following syntax: total = sum(of var1-var3);. Here, "of" indicates that SAS should treat the listed variables as a collection for the calculation.

In contrast, simply listing variable names without "of" may not convey the intended instruction for aggregating or performing operations across those variables. Other formatting options like brackets or equals signs do not align with SAS syntax for variable lists in functions, making them ineffective in this context.