Upon completion of this tutorial, you would understand how to create macros and where they can be used. It's generally said smart programming reduce workload and helps to win over your boss. Local - If the macro variable is defined inside a macro code, then scope is local.
It would be available for use in that macro only and gets removed when the macro is finished. Global - If the macro variable is defined outside a macro code, then scope is global.
It can be use any where in the SAS program and gets removed at the end of the session. Notice that unlike the PUT statement the text string is not enclosed in quotes. The quotes are not needed because, unlike in the DATA step, the macro facility does not need to distinguish between variable names and text strings.
Macro Parameters. Example : Suppose you are asked to write a macro that returns mean value of a variable. The analysis variable, input and output data sets are dynamic. How to call a macro -. Example : Calculate average height and store in a macro variable. It does not consider RUN statement. Usage III : It also preserves leading and trailing blanks of the string. So var1 returns 25 Detailed Tutorial : Multiple Ampersand Macro Variables How to store list of values in a macro variable Suppose you have a list of names and you want to store them in a macro variable.
We can use any other delimiter. See the detailed explanation of these two methods. Practice Question - Try it Yourself. Spread the Word! Share Share Tweet Subscribe. About Author: Deepanshu founded ListenData with a simple objective - Make analytics easy to understand and follow. These would not be good candidates for assignments in any case. Calling all SAS users! We now have even more FREE knowledge journeys. Learn more. Choose Your Journey. Sign In. Turn on suggestions.
Auto-suggest helps you quickly narrow down your search results by suggesting possible matches as you type. From the lesson Manipulating Data with Functions In this module, you learn to use some new functions that enable you to manipulate numeric, date, and character values.
Review of Functions Specifying Columns Lists Taught By. Stacey Syphus Senior Manager. Perl regular expressions build on the asterisk and the question mark to make searching more powerful and flexible. You can search for character strings that have a specific pattern that you specify, and change a matched substring to a different substring. PRX functions enable you to do the following:.
You can use Perl regular expressions to do the following:. You can write SAS programs that do not use regular expressions to produce the same results as you do when you use Perl regular expressions. The code without the regular expressions, however, requires more function calls to handle character positions in a string and to manipulate parts of the string. Perl regular expressions combine most, if not all, of these steps into one expression.
The resulting code has the following advantages. The PRX functions use a modified version of Perl 5. Perl is compiled into a library for use with SAS. The modified and original Perl 5. Each of the modified files has a comment block at the top of the file describing how and when the file was changed.
The executables were given non-standard Perl names. Only Perl regular expressions are accessible from the PRX functions.
Other parts of the Perl language are not accessible. The modified version of Perl regular expressions does not support the following:. This includes the syntax? Perl comments between a pattern and replacement text. Perl regular expressions are composed of characters and special characters that are called metacharacters.
When performing a match, SAS searches a source string for a substring that matches the Perl regular expression that you specify. Using metacharacters enables SAS to perform special actions when searching for a match:. The following table contains a short list of Perl regular expression metacharacters that you can use when you build your code. To match any character including newline, use a pattern such as "[. You can test for a pattern of characters within a string. For example, you can examine a string to determine whether it contains a correctly formatted telephone number.
This type of test is called data validation. The following example validates a list of phone numbers. The following items correspond to the lines that are numbered in the DATA step that is shown above. Use the following syntax elements to build the Perl regular expression:. Spaces are significant in Perl regular expressions. They match a space in the text that you are searching.
If a space precedes the question mark metacharacter as it does in this case , the pattern matches either zero spaces or one space in this position in the phone number. The concatenation enables you to search for both phone number formats from one regular expression.
The slashes around the entire pattern tell the compiler where the start and end of the regular expression is located.
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