To create a macro, you use the '%MACRO' statement followed by the macro name and any parameters. What do you code to create a macro? How do you end one? However, you can use the macro variable at any point in subsequent steps within the SAS program. When you use CALL SYMPUT in a DATA step, the macro variable created by it cannot be used in the same data step. If you use SYMPUT in a DATA step, when and where can you use the macro variable? A token is a fundamental unit of SAS code and is limited to 32,767 characters. The length of a macro variable is limited to 65,534 characters. How long can a macro variable be? A token? On the other hand, %GLOBAL is used to define a macro variable in open code, making it accessible throughout the SAS session. The variable is local to that specific macro and cannot be accessed outside of it. %LOCAL is used to define a macro variable inside a macro. What is the difference between %LOCAL and %GLOBAL? Making code modifications easier and more efficient. I have used SAS macros for various purposes, including:Įxecuting the same PROC step on multiple datasets.Ĭustomizing analysis and reporting based on different parameters. After writing the macro code, you use '%MEND' to indicate the end of the macro definition.įor what purposes have you used SAS macros?

The end of a macro is defined using the '%MEND' statement. For example, if you have a macro variable named 'var_name,' you would refer to it as '&var_name'. Macro variables in SAS are identified by the ampersand (&) sign followed by the variable name. You enclose the macro variable name in quotation marks and provide the value you want to assign. The general syntax is:ĬALL SYMPUT('macro-variable-name', value) This routine assigns a value from a data step to a macro variable. You can create a macro variable within a data step using the 'CALL SYMPUT' routine. How can you create a macro variable within a data step?

The semicolon at the end is optional but generally included for clarity. For example, if you have a macro named 'macro_name,' you would invoke it as '%macro_name '. To invoke a macro, you need to add the percent sign (%) prefix to its name. I have used macros primarily for creating analysis datasets and tables where it is necessary to make repetitive code changes throughout the program or reuse code segments. Yes, I have used macros extensively in my SAS programming projects. Have you used macros? For what purpose have you used them? In this blog post, we will delve into common interview questions related to SAS macros and provide comprehensive answers to help you gain a deeper understanding of their usage. They allow users to create reusable code segments and make programming more efficient. SAS macros are a powerful tool for automating and customizing repetitive tasks in SAS programming.

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