SAS Macro Programming Made Easy

2014·3.7 MB·English

by  Michele M. Burlew

Contents Page: iii
About This Book Page: ix
Purpose Page: ix
Is This Book for You? Page: ix
Prerequisites Page: ix
Scope of This Book Page: ix
About the Examples Page: x
Software Used to Develop the Book's Content Page: x
Example Code and Data Page: x
Additional Resources Page: x
Keep in Touch Page: xi
To Contact the Author through SAS Press Page: xi
SAS Books Page: xi
SAS Book Report Page: xi
Publish with SAS Page: xi
About The Author Page: xiii
Acknowledgments Page: xv
Part 1 Understanding the Concepts and Features of Macro Programming Page: 1
Chapter 1 Introduction Page: 3
What Is the SAS Macro Facility? Page: 4
Example 1.1: Using a Macro Variable to Select Observations to Process Page: 5
Example 1.2: Using a Macro Program to Execute the Same PROC Step on Multiple Data Sets Page: 5
What Are the Advantages of the SAS Macro Facility? Page: 5
Example 1.3: Defining and Using Macro Variables Page: 6
Where Can the SAS Macro Facility Be Used? Page: 11
Examples of the SAS Macro Facility Page: 12
Example 1.4: Displaying System Information Page: 12
Example 1.5: Conditional Processing of SAS Steps Page: 13
Example 1.6: Iterative Processing of SAS Steps Page: 15
Example 1.7: Passing Information between Program Steps Page: 16
Example 1.8: Interfacing Macro Language and SAS Language Functions Page: 18
Example 1.9: Building and Saving a Library of Utility Routines Page: 19
Chapter 2 Mechanics of Macro Programming Page: 21
Introduction Page: 21
The Vocabulary of SAS Processing Page: 21
SAS Processing without Macro Activity Page: 22
Understanding Tokens Page: 23
Tokenizing a SAS Program Page: 24
Comparing Macro Language Processing and SAS Language Processing Page: 26
Processing a SAS Program That Contains Macro Language Page: 27
Chapter 3 Macro Variables Page: 37
Introduction Page: 37
Basic Concepts of Macro Variables Page: 38
Referencing Macro Variables Page: 39
Example 3.1: Defining and Referencing Macro Variables Page: 39
Understanding Macro Variable Resolution and the Use of Single and Double Quotation Marks Page: 41
Example 3.2: Resolving Macro Variables Enclosed in Quotation Marks Page: 41
Displaying Macro Variable Values Page: 42
Using the %PUT Statement Page: 43
Example 3.3: Submitting %PUT _AUTOMATIC_ Page: 44
Example 3.4: Submitting %PUT _GLOBAL_ Page: 45
Example 3.5: Submitting %PUT Statements to Display Text and Macro Variable Values Page: 45
Displaying Macro Variable Values As They Resolve by Enabling the SYMBOLGEN System Option Page: 46
Example 3.6: Displaying Macro Variable Values with the SYMBOLGEN Option Page: 47
Understanding Automatic Macro Variables Page: 48
Example 3.7: Using Automatic Variables Page: 50
Understanding User-Defined Macro Variables Page: 51
Creating Macro Variables with the %LET Statement Page: 52
Example 3.8: Using the %LET Statement Page: 52
Combining Macro Variables with Text Page: 55
Placing Text before a Macro Variable Reference Page: 55
Example 3.9: Placing Text before a Macro Variable Reference Page: 55
Placing Text after a Macro Variable Reference Page: 57
Example 3.10: Placing Text after a Macro Variable Reference Page: 57
Concatenating Permanent SAS Data Set Names and Catalog Names with Macro Variables Page: 58
Example 3.11: Referencing Permanent SAS Data Set Names and Macro Variables Page: 59
Referencing Macro Variables Indirectly Page: 60
Example 3.12: Resolving Two Ampersands That Precede a Macro Variable Reference Page: 60
Example 3.13: Illustrating the Resolution of Macro Variable References When Combining Them Page: 61
Example 3.14: Resolving Multiple Ampersands That Precede a Macro Variable Page: 64
Chapter 4 Macro Programs Page: 67
Introduction Page: 67
Creating Macro Programs Page: 68
Example 4.1: Demonstrating a Macro Program Page: 71
Example 4.2 Page: 73
Executing a Macro Program Page: 74
Example 4.3 Page: 74
Displaying Notes about Macro Program Compilation in the SAS Log Page: 75
Displaying Messages about Macro Program Processing in the SAS Log Page: 77
Using MPRINT to Display the SAS Statements Submitted by a Macro Program Page: 77
Using the MLOGIC Option to Trace Execution of a Macro Program Page: 78
Passing Values to a Macro Program through Macro Parameters Page: 79
Specifying Positional Parameters in Macro Programs Page: 80
Example 4.4: Defining a Macro Program with Positional Parameters Page: 80
Specifying Keyword Parameters in Macro Programs Page: 82
Example 4.5: Defining a Macro Program with Keyword Parameters Page: 83
Specifying Mixed Parameter Lists in Macro Programs Page: 86
Example 4.6: Defining a Macro Program with Positional Parameters and Keyword Parameters Page: 86
Defining a Macro Program That Can Accept a Varying Number of Parameter Values Page: 89
Example 4.7: Defining a Macro Program with the PARMBUFF Option Page: 90
Chapter 5 Understanding Macro Symbol Tables and the Processing of Macro Programs Page: 95
Introduction Page: 95
Understanding Macro Symbol Tables Page: 95
Understanding the Global Macro Symbol Table Page: 97
Example 5.1: Referencing a Global Macro Variable in Open Code and from within a Macro Program Page: 98
Understanding Local Macro Symbol Tables Page: 101
Example 5.2: Referencing a Macro Variable Defined as a Parameter to a Macro Program – Version 1 Page: 102
Example 5.3: Referencing a Macro Variable Defined as a Parameter to a Macro Program – Version 2 Page: 105
Example 5.4: Referencing a Macro Variable Defined as a Parameter to a Macro Program – Version 3 Page: 106
Working with Global Macro Variables and Local Macro Variables Page: 108
Defining the Domain of a Macro Variable by Using the %GLOBAL or %LOCAL Macro Language Statements Page: 110
Example 5.5: Using the Same Name for a Macro Variable Defined Globally and Defined Locally Page: 111
Processing of Macro Programs Page: 114
How a Macro Program Is Compiled Page: 114
How a Macro Program Executes Page: 120
Chapter 6 Macro Language Functions Page: 129
Introduction Page: 129
Macro Character Functions Page: 130
Example 6.1: Using %SUBSTR to Extract Text from a Macro Variable Value Page: 131
Example 6.2: Using %SCAN to Extract the Nth Item from a Macro Variable Value Page: 131
Example 6.3: Using %UPCASE to Convert a Macro Variable Value to Uppercase Page: 132
Macro Evaluation Functions Page: 133
Macro Quoting Functions Page: 135
Macro Variable Attribute Functions Page: 137
Example 6.4: Using Macro Variable Attribute Functions to Determine Domain and Existence of Macro Va Page: 138
Other Macro Functions Page: 141
Using the %SYSFUNC and %QSYSFUNC Macro Functions Page: 141
Example 6.5: Using %SYSFUNC to Format a Date in the TITLE Statement Page: 142
Example 6.6: Using %SYSFUNC to Execute a SAS Language Function and Assign the Result to a Macro Vari Page: 142
Example 6.7: Using %SYSFUNC and the NOTNAME and NVALID SAS Language Functions to Determine If a Val Page: 143
Example 6.8: Using %SYSFUNC to Apply a SAS Statistical Function to Macro Variable Values Page: 144
Example 6.9: Using the %SYSFUNC Function to Apply Several SAS Language Functions That Obtain and Di Page: 145
SAS Supplied Autocall Macro Programs Used Like Functions Page: 147
Example 6.10: Determining with %VERIFY and %UPCASE If a Value Is in a Defined Set of Characters Page: 148
Chapter 7 Macro Expressions and Macro Programming Statements Page: 151
Introduction Page: 151
Macro Language Statements Page: 151
Constructing Macro Expressions Page: 154
Understanding Arithmetic Expressions Page: 155
Understanding Logical Expressions Page: 156
Understanding the IN Operator As Used in Macro Language Statements Page: 157
Conditional Processing with the Macro Language Page: 158
Example 7.1: Using Logical Expressions Page: 158
Example 7.2: Using Macro Language to Select SAS Steps for Processing Page: 160
Example 7.3: Using %IF-%THEN/%ELSE Statements to Modify and Select Statements within a Step Page: 162
Example 7.4: Writing %IF-%THEN/%ELSE Statements That Use the IN Operator Page: 166
Iterative Processing with the Macro Language Page: 167
Writing Iterative %DO Loops in the Macro Language Page: 167
Example 7.5: Building PROC Steps with Iterative %DO Loops Page: 167
Example 7.6: Building SAS Statements within a Step with Iterative %DO Loops Page: 169
Conditional Iteration with %DO %UNTIL Page: 170
Example 7.7: Building SAS Steps with %DO %UNTIL Loops Page: 170
Conditional Iteration with %DO %WHILE Page: 172
Example 7.8: Building SAS Steps with %DO %WHILE Loops Page: 172
Branching in Macro Processing Page: 174
Example 7.9: Using %GOTO to Branch in a Macro Program Page: 174
Chapter 8 Masking Special Characters and Mnemonic Operators Page: 177
Introduction Page: 177
Why Are Quoting Functions Called Quoting Functions? Page: 178
Illustrating the Need for Macro Quoting Functions Page: 179
Describing the Commonly Used Macro Quoting Functions Page: 180
%STR and %NRSTR Page: 180
%BQUOTE Page: 181
%SUPERQ Page: 181
Other Macro Quoting Functions: %NRBQUOTE, %QUOTE, and %NRQUOTE Page: 181
Understanding How Macro Quoting Functions Work Page: 181
Applying Macro Quoting Functions Page: 182
Example 8.1: Using %STR to Prevent Interpretation of the Semicolon As a SAS Statement Terminator Page: 182
Example 8.2: Using %STR to Prevent Interpretation of the Comma as an Argument Delimiter Page: 183
Example 8.3: Using %STR to Preserve Leading and Trailing Blanks Page: 184
Example 8.4: Using %NRSTR to Mask Macro Triggers Page: 185
Example 8.5: Using %STR to Mask Unbalanced Quotation Marks and Preceding Percent Signs Page: 186
Example 8.6: Masking Macro Triggers and Unbalanced Quotation Marks with %NRSTR and Preceding Percen Page: 187
Example 8.7: Using %BQUOTE to Prevent Interpretation of Mnemonic Operators Page: 187
Example 8.8: Using %SUPERQ to Prevent Resolution of Special Characters in a Macro Variable Value Page: 188
Specifying Macro Program Parameters That Contain Special Characters or Mnemonic Operators Page: 189
Example 8.9: Masking Special Characters in Parameter Values Page: 190
Example 8.10: Preventing Misinterpretation of Special Characters in Parameter Values Page: 191
Example 8.11: Masking Special Characters and Mnemonic Operators in Parameter Values Page: 193
Unmasking Text and the %UNQUOTE Function Page: 198
Example 8.12: Using %UNQUOTE to Cause Interpretation of a Masked Character Page: 198
Using Quoting Versions of Macro Character Functions and Autocall Macro Programs Page: 198
Example 8.13: Using %QSYSFUNC to Mask the Result from Applying a SAS Language Function Page: 199
Example 8.14: Using %QSUBSTR to Mask the Results of %SUBSTR Page: 200
Chapter 9 Interfaces to the Macro Facility Page: 201
Introduction Page: 201
Understanding DATA Step Interfaces to the Macro Facility Page: 201
Understanding the SYMGET Function Page: 202
Example 9.1: Using a Data Set Variable Name as the Argument to the SYMGET Function Page: 204
Example 9.2: Retrieving Macro Variable Values and Creating Numeric Data Set Variables with SYMGET Page: 206
Example 9.3: Using the Resolution of a Character Expression As an Argument to SYMGET Page: 207
Understanding the SYMPUT and SYMPUTX Call Routines Page: 209
Example 9.4: Saving the Sum of a Variable in a Macro Variable by Executing CALL SYMPUTX Once at the Page: 211
Example 9.5: Executing CALL SYMPUTX Multiple Times in a DATA Step Page: 213
Example 9.6: Creating Several Macro Variables with CALL SYMPUTX Page: 213
Example 9.7: Creating a Macro Variable with CALL SYMPUTX and Specifying Its Symbol Table Page: 214
Understanding the CALL EXECUTE Routine Page: 216
Example 9.8: Illustrating the Timing of CALL EXECUTE When It Invokes a Macro Program That Submits M Page: 217
Example 9.9: Illustrating the Timing of CALL EXECUTE When It Invokes a Macro Program That Submits M Page: 218
Example 9.10: Using CALL EXECUTE to Conditionally Call a Macro Program Page: 220
Example 9.11: Using CALL EXECUTE to Call a Specific Macro Program Page: 223
Understanding the RESOLVE Function Page: 227
Example 9.12: Obtaining Macro Variable Values with RESOLVE by Resolving Character Expressions Page: 228
Example 9.13: Using RESOLVE to Call a Macro Program within a DATA Step That Assigns Text to a Data Page: 230
Using Macro Facility Features in PROC SQL Page: 231
Creating and Updating Macro Variables with PROC SQL Page: 232
Example 9.14: Using the INTO Clause in PROC SQL to Save Summarizations in Macro Variables Page: 233
Example 9.15: Demonstrating the Default Action of the INTO Clause in Saving the First Row of a Tabl Page: 234
Example 9.16: Using the INTO Clause in PROC SQL to Create a Macro Variable for Each Row in a Table Page: 236
Example 9.17: Storing All Unique Values of a Table Column in One Macro Variable with PROC SQL Page: 237
Example 9.18: Storing All Values of a PROC SQL Dictionary Table Column in One Macro Variable Page: 237
Using the Macro Variables Created by PROC SQL Page: 238
Example 9.19: Using the PROC SQL SQLOBS Automatic Macro Variable Page: 239
Displaying Macro Option Settings with PROC SQL and Dictionary Tables Page: 241
Example 9.20: Accessing Macro Option Settings with PROC SQL and Dictionary Tables Page: 242
Example 9.21: Accessing Macro Variable Characteristics with PROC SQL and Dictionary Tables Page: 243
Part 2 Applying Your Knowledge of Macro Programming Page: 245
Chapter 10 Storing and Reusing Macro Programs Page: 247
Introduction Page: 247
Saving Macro Programs with the Autocall Facility Page: 248
Creating an Autocall Library Page: 248
Making Autocall Libraries Available to Your Programs Page: 250
Maintaining Access to the Autocall Macro Programs That Ship with SAS Page: 251
Defining Filerefs under Windows and Using Them to Identify Autocall Libraries Page: 251
Explicitly Specifying the Directory Locations of Autocall Libraries on the OPTIONS Statement Page: 252
Identifying Autocall Libraries That Are Stored in SAS Catalogs Page: 252
Listing the Names of the Autocall Libraries That Are Defined in the SAS Session Page: 252
Using the Autocall Facility under UNIX and z/OS Systems Page: 252
Using the Autocall Facility under UNIX Page: 252
Using the Autocall Facility under MVS Batch Page: 253
Saving Macro Programs with the Stored Compiled Macro Facility Page: 254
Setting SAS Options to Create Stored Compiled Macro Programs Page: 254
Creating Stored Compiled Macro Programs Page: 255
Example 10.1: Creating a Stored Compiled Macro Program Page: 256
Saving and Retrieving the Source Code of a Stored Compiled Macro Program Page: 257
Example 10.2: Saving the Source Code of a Stored Compiled Macro Program Page: 257
Encrypting a Stored Compiled Macro Program Page: 258
Example 10.3: Encrypting a Stored Compiled Macro Program Page: 258
Resolving Macro Program References When Using the Autocall Facility and the Stored Compiled Macro Fa Page: 258
Chapter 11 Building a Library of Utilities Page: 261
Introduction Page: 261
Writing a Macro Program to Behave Like a Function Page: 261
Example 11.1: Examining Specific Data Set Characteristics Page: 261
Example 11.2: Editing Character Data for Comparisons Page: 264
Programming Routine Tasks Page: 266
Example 11.3: Standardizing RTF Output Page: 266
Example 11.4: Documenting Characteristics of a Data Set Page: 269
Chapter 12 Debugging Macro Programming and Adding Error Checking to Macro Programs Page: 273
Introduction Page: 273
Understanding the Types of Errors That Can Occur in Macro Programming Page: 273
Minimizing Errors in Developing SAS Programs That Contain Macro Language Page: 274
Categorizing and Checking for Common Problems in Macro Programming Page: 275
Understanding the Tools That Can Debug Macro Programming Page: 278
Using SAS System Options to Debug Macro Programming Page: 278
Using Macro Language Statements to Debug Macro Programming Page: 279
Using Macro Functions to Debug Macro Programming Page: 280
Using Automatic Macro Variables to Debug Macro Programming Page: 280
Examples of Solving Errors in Macro Programming Page: 281
Example 12.1: Reviewing System Options When Macro Facility Warnings and Error Messages Are Absent Page: 281
Example 12.2: Attempting to Process a Macro Program When the Macro Processor Does Not Detect a %MEND Page: 283
Example 12.3: Tracing Problems in Expression Evaluation with the %PUT Statement and the MLOGIC Syste Page: 285
Example 12.4: Using %PUT to Trace a Problem at Execution Page: 289
Example 12.5: Finding a Logic Error in the Execution of a Macro Program with the MLOGIC Option Page: 292
Example 12.6: Using the MPRINT Option to Find Errors in SAS Language That Was Generated by Macro Lan Page: 296
Improving Your Macro Programming by Including Error Checking Page: 298
Example 12.7: Evaluating Parameter Values Page: 299
Example 12.8: Reviewing SAS Processing Messages Page: 301
Example 12.9: Reviewing SAS Processing Results Page: 303
Chapter 13 A Stepwise Method for Writing Macro Programs Page: 307
Introduction Page: 307
Building a Macro Program in Four Steps Page: 307
Applying the Four Steps to an Example Page: 308
Step 1: Write, test, and debug the SAS program(s) that you want the macro program to build Page: 309
Program for Report A with No Macro Facility Features Page: 309
Program for Report B with No Macro Facility Features Page: 310
Program for Report C with No Macro Facility Features Page: 314
Step 2: Remove hard-coded programming constants from the program(s) in Step 1 and replace these cons Page: 317
Program for Report A with Step 2 Modifications Page: 317
Program for Report B with Step 2 Modifications Page: 318
Program for Report C with Step 2 Modifications Page: 320
Step 3: Create macro program(s) from the program(s) in Step 2 Page: 321
Program for Report A with Step 3 Modifications Page: 321
Program for Report B with Step 3 Modifications Page: 322
Program for Report C with Step 3 Modifications Page: 324
Step 4: Refine and generalize the macro program(s) in Step 3 by adding macro language statements lik Page: 325
Executing the REPORT Macro Program Page: 328
Obtaining the Contents of Report A Using the REPORT Macro Program Page: 329
Obtaining the Contents of Report B Using the REPORT Macro Program Page: 331
Obtaining the Contents of Report C Using the REPORT Macro Program Page: 335
Enhancing the Macro Program REPORT Page: 338
Part 3 Appendixes Page: 339
Appendix A Sample Data Set Page: 341
Appendix B Reference to Examples In This Book Page: 343
Index Page: 355
A Page: 355
B Page: 355
C Page: 355
D Page: 355
E Page: 356
F Page: 356
G Page: 357
H Page: 357
I Page: 357
J Page: 357
K Page: 357
L Page: 357
M Page: 358
N Page: 361
O Page: 361
P Page: 361
Q Page: 362
R Page: 363
S Page: 363
T Page: 366
U Page: 367
V Page: 367
W Page: 367
Y Page: 367
Z Page: 367
Symbols Page: 367