SAS Macros part 2

Chapter 2. Using Macro Variable Venkata Maguluri

Section 2.1 Basic Concepts Basic Concepts

Objectives Learn where macro variables are stored. Substitute the value of a macro variable anywhere in a program. Monitor the value that is substituted when a macro variable is referenced. Display macro variable values and text in the SAS log. Basic Concepts

Global Macro Variables Whenever the SAS System is invoked, a global symbol table is created and initialized with automatic or system-defined macro variables. You can also create user-defined global macro variables with the %LET statement: %let city=Dallas; %let date=05JAN2000; %let amount=975; Automatic Variables Global Symbol Table . . . . SYSTIME 09:47 SYSVER 8.01 . . . . CITY Dallas DATE 05JAN2000 AMOUNT 975 User-defined Variables Basic Concepts

Referencing a Macro Variable To substitute the value of a macro variable in your program, you must reference it. A macro variable reference is made by preceding the macro variable name with an ampersand (&) causes the macro processor to search for the named variable and return its value if the variable exists. Basic Concepts

Referencing a Macro Variable Global Symbol Table CITY Dallas DATE 05JAN2000 AMOUNT 975 Example: Use a macro variable reference to make a substitution in a SAS program statement. where fee>&amount; generates WHERE FEE>975; Basic Concepts

Referencing a Macro Variable The word scanner continues to tokenize literals enclosed in double quotes, permitting macro variables to resolve. where cityst CONTAINS "&city"; generates WHERE CITYST CONTAINS "Dallas"; If you need to reference a macro variable within a literal, enclose the literal in double quotes. The word scanner does not tokenize literals enclosed in single quotes, so macro variables do not resolve. where cityst contains '&city'; generates WHERE CITYST CONTAINS '&city'; Basic Concepts Global Symbol Table CITY Dallas DATE 05JAN2000 AMOUNT 975

Referencing a Macro Variable Global Symbol Table CITY Dallas DATE 05JAN2000 AMOUNT 975 Referencing a nonexistent macro variable results in a warning message. title "Students from &cityst"; generates WARNING: Apparent symbolic reference CITYST not resolved. When the macro processor cannot act upon a macro variable reference, a message is printed in the SAS log. Basic Concepts

Referencing a Macro Variable Global Symbol Table CITY Dallas DATE 05JAN2000 AMOUNT 975 Referencing an invalid macro variable name results in an error message. title "Students from &the_city_in_which_the_student_is_located"; generates ERROR: Symbolic variable name THE_CITY_IN_WHICH_THE_STUDENT_IS_LOCATED must be 32 or fewer characters long. Basic Concepts

Displaying Macro Variable Values Use the SYMBOLGEN system option to monitor the value that is substituted for a macro variable referenced. General form of the SYMBOLGEN system option: OPTIONS SYMBOLGEN; This system option displays the results of resolving macro variable references in the SAS log. Note: The default option setting is NOSYMBOLGEN . Basic Concepts

Displaying Macro Variable Values Global Symbol Table CITY Dallas DATE 05JAN2000 AMOUNT 975 Partial SAS Log where fee>&amount; SYMBOLGEN: Macro variable AMOUNT resolves to 975 where city_state contains "&city"; SYMBOLGEN: Macro variable CITY resolves to Dallas where city_state contains ’&city’; Why is no message displayed for the final example? Basic Concepts

Displaying Macro Variable Values To verify the values of macro variables, you may want to write your own messages to the SAS log. The %PUT statement writes text to the SAS log. General form of the %PUT statement: %PUT text ; Basic Concepts

writes to the SAS log only always writes to a new log line starting in column one writes a blank line if text is not specified does not require quotes around tex t The %PUT statement continued... Displaying Macro Variable Values Basic Concepts

resolves macro triggers in text before text is written removes leading and trailing blanks from text unless a macro quoting function is used wraps lines when the length of text is greater than the current line size setting can be used inside or outside a macro definition. Displaying Macro Variable Values Basic Concepts

Example: Write a message to the SAS log to verify the value of the macro variable CITY. Global Symbol Table CITY Dallas DATE 05JAN2000 AMOUNT 975 Partial SAS Log %put The value of the macro variable CITY is: &city; The value of the macro variable CITY is: Dallas Displaying Macro Variable Values Basic Concepts

Section 2.2 Automatic Macro Variables

Objectives Identify selected automatic macro variables. Display values of automatic macro variables in the SAS log. Automatic Micro Variables

System-Defined Automatic Macro Variables are created at SAS invocation are global (always available) are usually assigned values by SAS can be assigned values by the user in some cases. These variables Automatic Micro Variables

Some automatic macro variables have fixed values that are set at SAS invocation: Name Value SYSDATE date of SAS invocation (DATE7.) SYSDATE9 date of SAS invocation (DATE9.) SYSDAY day of the week of SAS invocation SYSTIME time of SAS invocation SYSENV FORE (interactive execution) BACK (noninteractive or batch execution) SYSSCP abbreviation for the operating system used such as OpenVMS, WIN, HP 300 SYSVER release of SAS software being used SYSJOBID identifier of current SAS session or batch job mainframe systems:the userid or job name other systems: the process ID (PID). System-Defined Automatic Macro Variables Automatic Micro Variables

Some automatic macro variables have values that automatically change based on submitted SAS statements: System-Defined Automatic Macro Variables Automatic Micro Variables Name Value SYSLAST name of most recently created SAS data set in the form libref.nam e. If no data set has been created, the value is _NULL_. SYSPARM text specified at program invocation.

Example: Substitute system information in footnotes for a report. footnote1 "Created &systime &sysday, &sysdate9"; footnote2 "on the &sysscp system using Release &sysver"; title "REVENUES FOR DALLAS TRAINING CENTER"; proc tabulate data=perm.all(keep=location course_title fee); where upcase(location)="DALLAS"; class course_title; var fee; table course_title=" " all="TOTALS", fee=" "*(n*f=3. sum*f=dollar10.) / rts=30 box="COURSE"; run; System-Defined Automatic Macro Variables Automatic Micro Variables

System-Defined Automatic Macro Variables Automatic Micro Variables

The values of automatic macro variables can be displayed in the SAS log by specifying the _AUTOMATIC_ argument in the %PUT statement. %put _automatic_; System-Defined Automatic Macro Variables Automatic Micro Variables

Partial SAS Log The values of the macro variables SYSDATE, SYSDATE9, and SYSTIME are character strings , not SAS date or time values. System-Defined Automatic Macro Variables Automatic Micro Variables

Applications for Automatic Variables SYSDATE Check the current date to execute programs or on certain days of the month. Substitute SYSDATE9 the value in a TITLE statement. SYSDAY Check the value to run a given job on a certain day of the week. SYSENV Check the execution mode before submitting code that requires interactive(foreground) processing. Possible applications for automatic macro variables: Automatic Micro Variables

Applications for Automatic Variables SYSVER Check for the release of SAS software being used before executing a job with newer features. SYSJOBID Check who is currently executing the job to restrict certain processing or issue commands specific to a user . SYSERR Check the return code from a SAS procedure or DATA step and abort the job if the return code is nonzero. SYSRC Check the return code of any system command before continuing with the job. Automatic Micro Variables

The SYSPARM Macro Variable (Self-Study) OS/390 // EXEC SAS,OPTIONS='SYSPARM=SEATTLE' BATCH //SYSIN DD DSN= program-name,DISP=SHR TSO sas input(''' program-name''') opt('sysparm=SEATTLE') CMS sas program-name (sysparm=SEATTLE) OpenVMS sas/sysparm=SEATTLE program-name Windows sas program-name -sysparm SEATTLE UNIX Using the SYSPARM= system option to supply a value for the SYSPARM macro variable at SAS invocation. To assign the value SEATTLE to the SYSPARM macro variable, specify the SYSPARM= system option: Automatic Micro Variables

title "REVENUES FOR &sysparm TRAINING CENTER"; proc tabulate data=perm.all(keep=location course_title fee); where upcase(location)="&sysparm"; class course_title; var fee; table course_title=’ ’ all=’TOTALS’, fee=’ ’*(n*f=3. sum*f=dollar10.) / rts=30 box=’COURSE’; run; Example: Use one program to create a revenue report for any training center. Supply the name of the center at SAS invocation. The SYSPARM Macro Variable (Self-Study) Automatic Micro Variables

Output for SYSPARM Value of SEATTLE The SYSPARM Macro Variable (Self-Study) Automatic Micro Variables

Section 2.3 User-Defined Macro Variables

Objectives Create your own macro variables. Display values of user-defined macro variables in the SAS log. User-Defined Micro Variables

The %LET Statement The %LET statement enables you to define a macro variable and assign it a value. General form of the %LET statement: %LET variable = value ; User-Defined Micro Variables

Rules for the %LET statement: variable can be any name following the SAS naming convention. if variable already exists in the symbol table, value replaces the current value. if either variable or value contains a macro trigger, the trigger is evaluated before the assignment is made. continued... The %LET Statement User-Defined Micro Variables

Rules for the %LET statement: value can be any string: - maximum length is 32K characters - minimum length is 0 characters (null valu e) - numeric tokens are stored as character strings - mathematical expressions are not evaluated - the case of value is preserved - quotes bounding literals are stored as part of value - leading and trailing blanks are removed from value before the assignment is made. The %LET Statement User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; Value ... The %LET Statement Examples User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: ... %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; Value Ed Norton The %LET Statement Examples User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: Value Ed Norton ’ Ed Norton ’ ... %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; The %LET Statement Examples User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: Value Ed Norton ’ Ed Norton ’ “ Joan’s Report” ... %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; The %LET Statement Examples User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: Value Ed Norton ’ Ed Norton ’ “ Joan’s Report” 0 ... %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; The %LET Statement Examples User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: Value Ed Norton ’ Ed Norton ’ “ Joan’s Report” 0 3+4 ... %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; The %LET Statement Examples User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: Value Ed Norton ’ Ed Norton ’ “ Joan’s Report” 0+3+4 3+4 ... %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; The %LET Statement Examples User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: Value Ed Norton ’ Ed Norton ’ “ Joan’s Report” 0+3+4 3+4 varlist ... %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; The %LET Statement Examples User-Defined Micro Variables

Use the rules on the previous page to determine the values assigned to macro variables by these %LET statements: Value Ed Norton ’ Ed Norton ’ “ Joan’s Report” 0+3+4 3+4 varlist name age height ... %let name= Ed Norton ; %let name2=’ Ed Norton ’; %let title="Joan’s Report"; %let start=; %let total=0; %let sum=3+4; %let total=&total+∑ %let x=varlist; %let &x=name age height; The %LET Statement Examples User-Defined Micro Variables

Example: Assign the value DALLAS to the macro variable SITE. Use the macro variable to control program output. %let site=DALLAS; title "REVENUES FOR &site TRAINING CENTER"; proc tabulate data=perm.all(keep=location course_title fee); where upcase(location)="&site"; class course_title; var fee; table course_title=’ ’ all=’TOTALS’, fee=’ ’*(n*f=3. sum*f=dollar10.) / rts=30 box=’COURSE’; run; The %LET Statement Examples User-Defined Micro Variables

PROC TABULATE Output The %LET Statement Examples User-Defined Micro Variables

Displaying User-defined Macro Variables The values of user-defined macro variables can be displayed in the SAS log by specifying the _USER_ argument in the %PUT statement. %let city=Dallas; %let date=22MAY95; %let amount=795; %put _user_; continued... User-Defined Micro Variables

Note: The statement %put _all_; displays both automatic and user-defined macro variables. Partial SAS Log Displaying User-defined Macro Variables User-Defined Micro Variables

Tips on Writing Macro-based Programs write and debug the desired SAS program without any macro coding make sure the SAS program runs with hard-coded programming constants on a fixed set of data generalize the program by removing hard-coded programming constants and substituting macro variable references initialize the macro variables with %LET statements and try different values for the macro variables use the SYMBOLGEN system option to assist in debugging or confirmation. If you use a macro to generate SAS code, User-Defined Micro Variables

Objectives Use macro functions to manipulate character strings and other operations. Using Micro Functions

Many macro applications require character string manipulation. Selected macro character functions: %UPCASE translates letters from lowercase to uppercase. %SUBSTR produces a substring of a character string. %SCAN extracts a word from a character string. %LENGTH determines the length of a character string. Using Micro Functions

Macro functions have the same basic syntax as the corresponding DATA step functions and yield similar results. Manipulating Character Strings Using Micro Functions

Most comparison operators in the SAS language are case sensitive. Example: Create a summary of total fees outstanding for each course. %let paidval=n; proc means data=perm.all sum maxdec=0; where paid="&paidval"; var fee; class course_title; title "Outstanding Fees for Each Course"; run; Using Micro Functions

Because the value of the macro variable PAIDVAL was specified in lowercase , the WHERE expression finds no matching observations. All the values of the data set variable PAID are in uppercase . Partial Log Case of Text Issues Using Micro Functions

You can use the %UPCASE function to translate the value of a macro variable to uppercase before substituting its value in a SAS program. General form of the %UPCASE function: % UPCASE ( argumen t) Case of Text Issues Using Micro Functions

Example: For each course, create a summary of total fees outstanding and account for case. %let paidval=n; proc means data=perm.all sum maxdec=0; where upcase(paid)=”%upcase(&paidval)"; var fee; class course_title; title "Outstanding Fees for Each Course"; run; Case of Text Issues Using Micro Functions

Case of Text Issues Using Micro Functions

Extracting Parts of Strings requires the first two arguments. The third argument is optional. returns the portion of argument beginning at position for a length of n characters. The %SUBSTR function General form of the %SUBSTR function: %SUBSTR ( argumen t, position < ,n >) continued… Using Micro Functions

returns the portion of argument beginning at position to the end of argument when an n value is not supplied. produces a warning and reads from position to the end of argumen t, if a n n value is supplied that extends beyond the bounds of argumen t. Extracting Parts of Strings Using Micro Functions

constant text macro variable references macro functions macro calls. You can specify argumen t, positio n, and n values using General form of the %SUBSTR function: %SUBSTR ( argumen t, position < ,n >) It is not necessary to place argument in quotes because it is always handled as a character string by the %SUBSTR function. Extracting Parts of Strings Using Micro Functions

Example: Print all courses held since the start of the current month. Use the %SUBSTR function and SYSDATE9 macro variable to determine the month and year. proc print data=perm.schedule; where begin_date between "01%substr(&sysdate9,3)"d and "&sysdate9"d; title "All Courses Held So Far This Month"; title2 "(as of &sysdate9)"; run; Extracting Parts of Strings Using Micro Functions

Extracting Parts of Strings Using Micro Functions

You can assign several words to a macro variable’s value and extract them with the %SCAN function. General form of the %SCAN function: %SCAN ( argument , n < , delimiter s>) Extracting Parts of Strings Using Micro Functions

requires the first two arguments . returns the nth word of argumen t , where words are strings of characters separated by delimiters. Consecutive delimiters are treated as one delimiter. uses a default set of delimiters if none are specified. returns a null string if there are fewer than n w ords in argumen t. The %SCAN function Extracting Parts of Strings Using Micro Functions

constant text macro variable references macro functions macro calls. %SCAN ( argument , n < , delimiter s>) You can specify values for argument , n , and delimiters using The value of n can also be an arithmetic expression that yields an integer . Extracting Parts of Strings Using Micro Functions

Example: Use PROC DATASETS to investigate the structure of the last data set created. data work.thisyear; set perm.schedule; where year(begin_date) = year(“sysdate9”d); run; %let libref=%scan(&syslast,1); %let dsname=%scan(&syslast,2,.); proc datasets lib=&libref nolist; title "Contents of the Data Set &syslast"; contents data=&dsname; run; quit; Extracting Parts of Strings Using Micro Functions

Partial Output Extracting Parts of Strings Using Micro Functions

By using the automatic macro variables SYSDATE9 and SYSTIME you can include the date and time in a title: title "Report Produced on &sysdate9."; title2 "at &systime."; generates Using Micro Functions

SYSDATE9 represents the date that the SAS session started and SYSTIME represents the time the SAS session started . If you started your interactive SAS session at 10:30 PM yesterday, what date and time would be in your report? What if you wanted to see the date or time in some other format besides DATE9.? Other SAS Functions Using Micro Functions

You can utilize the %SYSFUNC macro function to execute SAS functions. Example: The following code was submitted on Friday, June 9, 2000: title "%sysfunc(today(),weekdate.) - SALES REPORT"; The title on the next report would be Friday, June 9, 2000 – SALES REPORT Other SAS Functions Using Micro Functions

General form of the %SYSFUNC function: %SYSFUNC (function(argument(s)) <,format>) The first argument is required . The second argument is optional . function(argument(s)) is the name of one of most SAS functions and the corresponding arguments. Other SAS Functions Using Micro Functions

All SAS functions can be used with %SYSFUNC except: DIF DIM HBOUND IORCMSG INPUT LAG LBOUND MISSING PUT RESOLVE SYMGET All Variable Information Functions Other SAS Functions Using Micro Functions

Combining Macro Variable References with Text

Objectives Place a macro variable reference adjacent to text or another macro variable reference. Combining Micro Variable references with Text

You can reference macro variables anywhere in your program. Some applications may require placing a macro variable reference adjacent to leading and/or trailing text tex t &variable &variable text tex t &variable text or referencing adjacent macro variables &variable &variable in order to build a new token. Combining Macro Variable references with Text

You can place text immediately before a macro variable reference to build a new token. Example: Data sets are stored in a SAS data library with this naming convention: Y yymon yy can be 90 , 91 , 92 , 93 , 94 , and so on. mon can be JAN , FEB , MAR , and so on. Write a program that uses a macro variable to build the month portion of the SAS data set name. Combining Macro Variable references with Text

%let month=jan; proc chart data=perm.y90 &month ; hbar week / sumvar=sale; run; proc plot data=perm.y90 &month ; plot sale*day; run; PROC CHART DATA=PERM.Y90 JAN ; HBAR WEEK / SUMVAR=SALE; RUN; PROC PLOT DATA=PERM.Y90 JAN ; PLOT SALE*DAY; RUN; generates Combining Macro Variables with Text Combining Micro Variable references with Text

You can reference macro variables that have no blanks between them to build new tokens. Example: Modify the previous program to allow both the month and the year to be substituted. %let year=90 ; %let month=jan; proc chart data=perm.y &year &month; hbar week / sumvar=sale; run; proc plot data=perm.y &year &month; plot sale*day; run; Combining Macro Variables with Text Combining Micro Variable references with Text

PROC CHART DATA=PERM.Y 90 JAN; HBAR WEEK / SUMVAR=SALE; RUN; PROC PLOT DATA=PERM.Y 90 JAN; PLOT SALE*DAY; RUN; The generated program is identical to the program in the previous example. Combining Macro Variables with Text Combining Micro Variable references with Text

You can place text immediately after a macro variable reference if it does not change the macro variable name. Example: Modify the previous program to substitute the name of an analysis variable. %let year=90; %let month=jan; %let var=sale; proc chart data=perm.y&year&month; hbar week / sumvar =&var ; run; proc plot data=perm.y&year&month; plot &var *day; run; Combining Macro Variables with Text Combining Micro Variable references with Text

PROC CHART DATA=PERM.Y90JAN; HBAR WEEK / SUMVAR= SALE ; RUN; PROC PLOT DATA=PERM.Y90JAN; PLOT SALE *DAY; RUN; The generated program is identical to the program in the previous example. Combining Macro Variables with Text Combining Micro Variable references with Text

Example: Modify the previous program to allow a base SAS or SAS/GRAPH procedure. /* GRAPHICS should be null or G */ %let graphics=g ; %let year=90; %let month=jan; %let var=sale; proc &graphicschart data=perm.y&year&month; hbar week / sumvar=&var; run; proc &graphicsplot data=perm.y&year&month; plot &var*day; run; What is wrong with this program? Combining Macro Variables with Text Combining Micro Variable references with Text

SAS interprets the macro variable’s name to be GRAPHICSCHART because there is no delimiter between the macro reference and the rest of the text. Partial Log Combining Macro Variables with Text Combining Micro Variable references with Text

Macro Variable Name Delimiter The word scanner recognizes the end of a macro variable name when it encounters a character that cannot be part of the name token. A period ( .) is a special character that is treated as part of the macro variable reference and does not appear when the macro variable is resolved. Combining Micro Variable references with Text

Example: Correct the resolution problem in the previous example. %let graphics=g; %let year=90; %let month=jan; %let var=sale; proc &graphics. chart data=perm.y&year&month; hbar week / sumvar=&var; run; proc &graphics. plot data=perm.y&year&month; plot &var*day; run; Macro Variable Name Delimiter Combining Micro Variable references with Text

word scanner treats &graphics. as the reference value of the macro variable GRAPHICS is returned to the input stack word scanner processes gchart as one token. If these SAS statements are executed, the PROC GCHART DATA=PERM.Y90JAN; HBAR WEEK / SUMVAR=SALE; RUN; PROC GPLOT DATA=PERM.Y90JAN; PLOT SALE*DAY; RUN; The SAS compiler receives Macro Variable Name Delimiter Combining Micro Variable references with Text

Example: Modify the previous program to include a macro variable used to define the libref. %let lib=perm; %let graphics=g; %let year=90; %let month=jan; %let var=sale; libname &lib ’SAS-data-library’; proc &graphics.chart data =&lib. y&year&month; hbar week / sumvar=&var; run; proc &graphics.plot data =&lib. y&year&month; plot &var*day; run; What is the problem this time? Macro Variable Name Delimiter Combining Micro Variable references with Text

The statements %let lib=perm; ... libname &lib 'SAS-data-library'; proc &graphics.chart data= &lib .y &year&month ; ... proc &graphics.plot data =&lib .y &year&month ; LIBNAME PERM 'SAS-data-library'; PROC GCHART DATA= PERM Y 90JAN ; HBAR WEEK / SUMVAR=SALE; RUN; PROC GPLOT DATA= PERM Y 90JAN ; PLOT SALE*DAY; RUN; send these statements to the SAS compiler: The period after &lib is interpreted as a delimiter. Macro Variable Name Delimiter Combining Micro Variable references with Text

Use another period after the delimiter period to supply the needed token. %let lib=perm; ... libname &lib 'SAS-data-library'; proc &graphics.chart data= &lib ..y &year&month ; ... proc &graphics.plot data =&lib ..y &year&month ; Macro Variable Name Delimiter Combining Micro Variable references with Text

proc &graphics.chart data= &lib ..y &year&month ; ... PROC GCHART DATA= PERM .Y 90JAN ; ... The first period is treated as a macro variable name delimiter. The second period is simply text. The compiler receives delimiter text Macro Variable Name Delimiter Combining Micro Variable references with Text

Objectives Describe when macro quoting functions are needed. Protect tokens so the word scanner and macro processor interpret them properly. Quoting Micro Facility

The SAS language uses matched pairs of quotes to distinguish character constants from names. The quotes are not stored as part of the token they define. data one; var='TEXT'; run; VAR is stored as a four-byte variable with the value TEXT . If TEXT were not enclosed in quotes, it would be treated as a variable name . Quoting Micro Facility

proc print; title "Joan’s Report"; run; The title text is Joan’s Report and does not contain the outer matched quotes . The outer quotes are double quotes to prevent ambiguity with respect to the unmatched single quote (apostrophe) within the text. Quoting Micro Facility

Suppose you want to store one or more SAS statements in a macro variable. options symbolgen; %let prog=data new; x=1; run; &prog proc print; run; Quoting Micro Facility

How do you explain the processing reported in this SAS log? Quoting Micro Facility

In the previous example, SAS interpreted the first “;” as the end of the macro assignment statement. In some applications you need to mask the meaning of text you want to assign to a macro variable. You can use macro quoting functions to remove the normal syntactic meaning of tokens. Need for Macro Quoting Quoting Micro Facility

The %STR function is used to protect (quot e) tokens so the macro processor does not interpret them as macro-level syntax. General form of the %STR function: %STR ( argumen t) argument can be any combination of text and macro triggers. Quoting Micro Facility

removes the normal meaning of a semicolon and other special tokens that appear as constant text. Other special tokens include: The %STR function + - * / , < > = blank LT EQ GT AND OR NOT LE GE NE continued... The %STR Function Quoting Micro Facility

allows macro triggers to work normally preserves leading and trailing blanks in its argument. The %STR function also Note: The %NRSTR function performs the same quoting function as %STR, except it also quotes macro triggers (& and %). The %STR Function Quoting Micro Facility

There are a number of ways that text can be quoted. Method One: Quote all text. %let prog=%str(data new; x=1; run;); The %STR Function Quoting Micro Facility

Method Two: Quote only the semicolons. %let prog=data new%str(;) x=1%str(;)run%str(;); The %STR Function Quoting Micro Facility

Method Three: Create a macro variable with a quoted value. %let s=%str(;); %let prog=data new&s x=1&s run&s; The %STR Function Quoting Micro Facility

Example: Use the %STR function to store one or more SAS statements as the value of the macro variable PROG. Display the value of PROG through the SYMBOLGEN system option using a %PUT statement. The %STR Function Quoting Micro Facility

The %STR Function Quoting Micro Facility

options symbolgen; %let text=Joan’s Report; proc print data=perm.courses; where days >3; title "&text"; run; Example: Suppose you want to assign text containing an apostrophe to a macro variable. The %STR Function Quoting Micro Facility

Partial SAS Log The %STR Function Quoting Micro Facility

The word scanner interprets the apostrophe as the beginning of a literal defined by a pair of single quotes. The %STR function can also be used to quote tokens that normally occur in pairs: ’ " ) ( The %STR Function Quoting Micro Facility

To perform this quoting, you must precede any of the above tokens with a percent sign within the %STR function argument. %let text=%str(Joan % ’s Report); %let text=Joan%str( % ’)s Report; The value of TEXT is Joan’s Report in both cases. The %STR Function Quoting Micro Facility

options symbolgen; %let text=%str(Joan%’s Report); proc print data=perm.courses; where days >3; title "&text"; run; %put The value of TEXT is: &text; Example: Use the %STR function to assign text containing an apostrophe to a macro variable. The %STR Function Quoting Micro Facility

You were earlier introduced to the %SYSFUNC macro function and used it to include a date in a title. For example, title "Report Produced on sysfunc(today(),mmddyy10.)"; results in the title Report Produced on 06/12/2000 for a report run on June 12, 2000. Quoting Micro Facility

If you wanted to use a different format, the results may not be what you expect. For example, title "Report Produced on %sysfunc(today(),worddate.)"; results in the title: Report Produced on June 12, 2000 Quoting with %SYSFUNC (Self-Study) Quoting Micro Facility

The extra blanks are from the default length of worddate . You need to left-justify the resulting formatted date. Quoting with %SYSFUNC (Self-Study) Quoting Micro Facility

You cannot nest functions within %SYSFUNC, but you can use a %SYSFUNC for each function needed. Quoting with %SYSFUNC (Self-Study) Quoting Micro Facility

However, the code title “Report Produced on %sysfunc(left(%sysfunc(today(),worddate.))))”; results in the following error message: ERROR:The function LEFT referenced by the %SYSFUN or %QSYSFUNC macro function has too many arguments. Quoting with %SYSFUNC (Self-Study) Quoting Micro Facility

The LEFT function expects only one argument. However, you are passing it "June 12, 2000". It is interpreting the comma as the delimiter between two arguments. Quoting with %SYSFUNC (Self-Study) Quoting Micro Facility

You can mask the comma by using the %QSYSFUNC function instead: title "Report Produced on %sysfunc(left(%qsysfunc(today(),worddate.))))"; The title is now: Report Produced on June 12, 2000 Quoting with %SYSFUNC (Self-Study) Quoting Micro Facility

SAS Macros part 2

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SAS Macros part 2