How a macro program is compiled 114 how a macro program executes 120. You seem to want to create macro variables in one data step program and then you want to do a lookup from those macro variables in a second data step program based on some value from data in the second data step program. The macro function %str can be used, for example, to pass an entire statement into a macro. Create your own functions using sasmacro and scl lex jansen. The macro quoting functions is one of the most difficult concepts to grasp when one learns to write a macro program. Upon completion of this tutorial, you would understand how to create macros and where they can be used. It also allows formatting of macro variable values using native sas formats, or userspecified formats.
Functions that create sas date, datetime, and time values the first three functions in this group of functions create sas date values, datetime values, and time values from the constituent parts month, day, year, hour, minute, second. Macro functions include character functions, evaluation functions, and quoting functions. May 04, 2019 through this sas function cheat sheet, you will be learning different types of functions in sas. Sas tutorial for beginners to advanced practical guide. Suppose, we want to create a macro function that takes a data set name as an argument and returns a value. This example stores three words in the macro variable. Special functions inputvalue, informat performs charactertotonumeric conversion. With the %str function, all the text with the parentheses is assigned to the macro variable. For example, the input function can be used to return a numeric value back to the user based on a character value and a valid sas format. Sas macro provides an incredible way to make a process easy and automatic. It can never return a value, though in some cases you can mimic functions.
Using this function, we can report length of the macrovariable. Common examples are terminating a program when some condition is met or capturing the runtime value of a variable in the program log. Without the %str function, the text assigned to each macro variable would end at the first semicolon. Youll need the references added in your vba project which you mentioned. You can use all macro functions in both macro definitions and open code. Selected system options used in the macro facility tree level. The functions are again based on proc lifereg in sas and the package survival in r. This means by the time the macro executes, the string is already masked by a macro quoting function. Using sas macro functions to manipulate data midwest sas. The macro language functions are listed in the following table.
My main concern here is how to return a value from a macro. Executing sas functions with the %sysfunc macro function. Macro variables are character variables so the %eval function may be required. Printing the statements generated during macro execution to a file is useful for debugging macros when you want to test generated text in a later sas session. While you do not need to end this statement with a semicolon, it generally does no harm either.
I think the issue is the language, and how sas is sending my statements to the macro processor vs. Addressing the composition and operation of the sas macro facility and the sas macro language, this third edition offers nearly 400 readytouse macros, macro functions, and macro tools that enable you to convert sas code to macros, define macro variables, and more. Execute sas program via vba sas support communities. Abstract the macro facility is an important feature of the sas language. They are used by other sas programs without explicitly declaring them. In macros, we can write functions inside or outside of the macroblock global function a % length. Different macro quoting functions mask different special characters and mnemonics so the macro facility interprets them as text instead of as macro language symbols. Functions are applied to a single variable or to a set of variables for analyzing. Reference a macro language function processes one or more arguments and produces a result. Therefore, %str and %nrstr are useful for masking strings that are constants, such as sections of sas code. Writing cleaner and more powerful sas code using macros myweb. Sas macro functions %eval and %sysevalfeverything technical. While data step functions are applied to values on a vector of variables, macro functions are used to create, modify, and work with text strings. In additonal, there is a decided advantage to being able to calculate values outside of a data step, because adding another.
Macro functions operate much as regular sas functions,except that the arguments are within the context of the macro language. As tom has pointed out, knowing base sas as well as possible is the best route to minimising code. In macros, we can write functions inside or outside of the macroblock global function. To find pseudovalues for the cumulative incidence functions the sas macro pseudoci and the r function pseudoci are available.
Lets discuss some examples of sas macro variable and sas macros, when. This seminar is designed to introduce the basics of sas macro language. Sas functions byten returns one character in the ascii or ebcdic collating sequence where n is an integer representing a specific ascii or ebcdic character. It covers topics on proc sql, sas macros, advanced data manipulation case studies.
Of all the macro quoting functions, only %nrstr and %str take effect during compilation. Knowing sas macros is an advantage in the job market over other candidates. Catx enhanced string concatenation there are many ways to concatenate strings in sas. Therefore, %str and %nrstr are useful for masking strings that are constants, such as sections of sas. Macros make it easy to produce and execute complex sas programs which would be timeconsuming to write yourself. A sas function performs a computation or system manipulation on arguments, and returns a value that can be used in an assignment statement or elsewhere in expressions. No longer do you have to write witty or complex code to get around the non macro function issue. In this seminar we will cover the following topics. Selected autocall macros provided with sas software tree level 3. It includes some common tricky and tough questions that are generally asked in an interview. Place all sas data set variables into a macro variable. Aug 02, 2012 the %sysevalf function evaluates arithmetic and logical expressions using floatingpoint arithmetic and returns a value that is formatted using the best32. In sas component control language scl programs, returns the value of a global macro variable as a numeric value. Im going to quibble with dirk here in an important way.
However, %quote and %nrquote work during macro execution. Ok firstly lets try to use iom to start a local sas workspace server session and run a simple piece of code. Explains how to increase the modularity, flexibility, and maintainability of your sas code using the sas macro facility. Mastering this facility will enable the novice user to become an accomplished programmer. Manipulating macro variable values with macro functions. These questions are best suited for interviews for sas developer, sas programmer role.
Summary of macro quoting functions and the characters that they mask sas 9. A macro language function processes one or more arguments and produces a result. To use this feature, set both the mfile and mprint system options on and also assign mprint as the fileref for the file to contain the output generated by the macro facility. This tutorial explains sas macros with practical examples. Symgetn function macro function sclvariable symgetn macro variable. Understanding and using the macro facility tree level 1. Summary of macro quoting functions and the characters they. Im having an issue with resolving macro variables within a macro. Creating a sas date variable several methods exist to create a date, time or datetime variable either from raw data or from numeric variables in an existing sas data set. Sas has a powerful programming feature called macros which allows us to avoid repetitive sections of code and to use them again and again when needed. Using normal sas functions in macro processing some of the magic in advanced macro processing comes from the ability to use normal sas functions, sometimes referred to as data step functions. Carpenter, california occidental consultants abstract many macro functions are very analogous to those of the data step.
The code below must do the same thing in three different ways using the data step, sas iml, and sas macro, respectively, but unfortunately the third one doesnt work and just produces some warning messages saying warning. It receives only the results of these functions because these functions work when a macro compiles. It also helps create dynamic variables within the code that can take different values for different run instances of the same code. There are several enhancements to the macro language facility including a new automatic macro variable, new comparison operators, new sas system options, new macro statements, new functions, and a new option for the % macro statement. Back in the older versions of sas there was a fair bit of functionality that was missing, and macro conviniently filled in there.
These macro functions have similar syntax, compared to their. May 01, 2019 sas macro provides an incredible way to make a process easy and automatic. This section describes the features of the sas macro facility that are new or enhanced since sas 8. How to create and use sas macro functions sas users sas blogs. Also, there are some sas language functions that are not accessible using %sysfunc. Macro facility error messages and debugging sas institute. The %sysevalf function evaluates arithmetic and logical expressions using floatingpoint arithmetic and returns a value that is formatted using the best32. The macro language functions are listed in macro functions. A sas date value is a constant that represents a fixed value. Macro functions process macro expressions, called arguments, to produce a new expression.
Selects observations from a sas data set that meet certain conditions before sas brings them into the data or proc step for processing. However, their usage by general base sas users is precluded by affordability, availability and flexibility. Manipulate values of sas variables manipulatevalues of macro variables executed when the data or proc step in which they are included is executed executed at word scanning time by the macro processor over 500 available in sas 9. Valueis a character variable informatis a sas is a sas informatinformat, defines the input format of, defines the input format of value putvalue, format performs numeric totocharacter conversion. In general, a macro language function processes one or more arguments and produces a result. The %upcase and %qupcase functions convert lowercase characters in the argument to uppercase. The macro facility is a tool for extending and customizing the sas system and for reducing the amount of text you must enter to do common tasks. The terms compiletime and runtime should be understood as related to macro for mastery of macro quoting functions.
Macros macros consist of collections of regular sas program statements, macro variables, macro language statements, and macro functions contained within a % macro and a %mend. A practical sas macro for converting rtf to pdf files. Macro functions are fun to write, they reduce the possibilities of macro variable collisions, and best of all, they can be used to impress your date after the movies. Moreover, we learn components of sas macro code and some benefits of sas macro. Dec 22, 2015 now, lets understand the use of macro functions to manipulate text, perform arithmetic operations and execute sas functions. A sas macro is a program that generates sas statements.
It includes useful tips and tricks of sas macro programming and outlines real world examples of automation with sas macros. In base sas software, you can use sas functions in data step programming statements, in a where expression, in macro language. There are some sas macro functions which help you to execute various operations within a macro. While data step functions are applied to values on the program data vector, pdv, macro functions are used to create, modify, and work with text strings. Sas has many macro statements which are in built in the sas programming language. Valueis a character variable informatis a sas is a sas informatinformat, defines the input format of, defines the input format of. References burlew, michele, sas macro programming made easy, cary, nc. Arthur li, city of hope national medical center, duarte, ca. Similarly, functions and macros can also be developed by user based on his needs and requirements. Dec 05, 2019 understanding and using the macro facility tree level 1. Your macro programs can be as free as your open code. One of the reasons for its complexity is closely related to understanding the macro processing, such as macro.
Sas macro language question sas support communities. Summary of macro quoting functions and the characters they mask. Sas macro programming is considered as an advanced sas. The other macro quoting functions take effect when a macro executes. We will introduce interaction between macros and regular sas language, offer tips on debugging macros, and discuss sas macro options. It will help the novice sas user bridge the gap between beginner and expert programmer. Sas macros for faster data manipulation complete tutorial.
Sas macros and functions sas macros provided with sas ets software this chapter describes several sas macros and the sas function probdf that are provided with sas ets software. Valueis a character variableis a character variable. Initially this may seem like a minor difference, but because macro functions deal with. This paper presents an alternative effective method where a practical sas macro was developed and utilized under 2 scenarios. Sas macro functions vs data step functions stack overflow. If the argument is a character string, %length returns the length of the string. Japanese privacy statement terms of use copyright sas institute inc. These are the most frequently asked advanced sas interview questions and answers. Sas programming facilities and works with existing code. Since the sas macro facility stores all values as a text string, there may be times when you want to. In this paper, we will walk through the various types of functions, macros, and how the functions and macros are stored and processed internally. Sas is rich in various builtin functions, and predefined sas supplied macros.
You will also understand how sas functions can be used to make our program less lengthy and easy to read with the help of examples. Syntax for selected sas functions used with the %sysfunc function. Different macro quoting functions mask different special characters and mnemonics so that the macro facility interprets them as text instead of as macro language symbols. If the argument is a text expression, %length returns the length of the resolved value. Macro functions macro functions operate much as regular sas functions, except that the arguments are within the context of the macro language. The big mystery for many, %sysfunc is a mysterious macro function with little documentation or discussion. The macro checkds uses %sysfunc to execute the exist function, which. Here, we will see different sas macro variables, functions of macro in sas programming language. Argument 2 to function putn referenced by the %sysfunc or %qsysfunc macro function is out of range.
The differences and timing of the compiletime macro quoting functions, %str and %nrstr, will be emphasized. Provides complete information about macro language elements, interfaces between the sas macro facility and other parts of sas software, and macro processing in general. These macro functions have similar syntax, compared to their counterpart functions in data steps and they also return results in similar manner. Oct 24, 2016 i am writing a macro and trying to find the string using index function from a parameter that is being passed in the macro. Sas macro quoting functions also are used to mark starting and ending delimiters. The functions here are grouped into three categories. Sas macros sas macro is used to automate the repetitive tasks i. Writing cleaner and more powerful sas code using macros.
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