SAS Chapter 9: Introducing Macro Variables

1. Macro character functions

Can be used to manipulate character strings in macro variable values.

Have the same basic syntax as the corresponding DATA step functions and yield similar results.

All of the above

None of the above

Macro character functions such as %UPCASE and %SUBSTR enable you to perform character manipulations on your macro variable values.

Explanation

Macro character functions such as %UPCASE and %SUBSTR enable you to perform character manipulations on your macro variable values.

2. Which of the following statements is false?

A macro variable can be defined and referenced anywhere in a SAS program except within data lines.

Macro variables are always user-defined, and their values remain constant until they are changed by the user.

Macro variables are text strings that are independent of SAS data sets.

The values of macro variables can be up to 65,534 characters long.

Macro variables are always text strings that are independent of SAS data sets. The value of a macro variable can be up to 65,534 characters long, and the name of a macro variable can be up to 32 characters long. A macro variable can be defined or referenced anywhere in a SAS program except within data lines. There are two types of macro variables: automatic and user-defined.

Explanation

Macro variables are always text strings that are independent of SAS data sets. The value of a macro variable can be up to 65,534 characters long, and the name of a macro variable can be up to 32 characters long. A macro variable can be defined or referenced anywhere in a SAS program except within data lines. There are two types of macro variables: automatic and user-defined.

3. Assuming that you began your SAS session today, which of the following statements correctly sets the macro variable currdate to today's date:

%let currdate = %sysfunc(today(), worddate.);

%let currdate = &sysdate9;

%let currdate = %sysfunc(date());

All of the above

SYSDATE9 is an automatic macro variable that stores the date that your SAS session began in ddmmmyyyy format. You can use the %SYSFUNC function along with any DATA step function, so both the TODAY() function and the DATE() function will result in the current date.

Explanation

SYSDATE9 is an automatic macro variable that stores the date that your SAS session began in ddmmmyyyy format. You can use the %SYSFUNC function along with any DATA step function, so both the TODAY() function and the DATE() function will result in the current date.

4. Which statement will create a macro variable named location that has the value storage?

&let location = storage;

Let &location = storage;

%let location = "storage";

%let location = storage;

You use the %LET statement to define a macro variable. You do not need to enclose the value in quotation marks. If you do include quotation marks in the assigned value for a macro variable, the quotation marks will be stored as part of the value.

Explanation

You use the %LET statement to define a macro variable. You do not need to enclose the value in quotation marks. If you do include quotation marks in the assigned value for a macro variable, the quotation marks will be stored as part of the value.

5. Which of the following statements will generate an error message while trying to display the value of the macro variable month in the SAS log?

Options &month;

%PUT &month;

Options symbolgen;

%PUT the macro variable MONTH has the value &month.;

There are two ways to display the value of a macro variable in the SAS log: you can turn on the SYMBOLGEN system option to list the values of all macro variables that are used, or you can use the %PUT statement to write specific text, including macro variable values, to the log.

Explanation

There are two ways to display the value of a macro variable in the SAS log: you can turn on the SYMBOLGEN system option to list the values of all macro variables that are used, or you can use the %PUT statement to write specific text, including macro variable values, to the log.

6. What value will these statements assign to the macro variable reptitle:

%let area = "Southeast";
%let reptitle = *   Sales Report for &area Area   *;

Sales Report for Southeast Area

Sales Report for "Southeast" Area

*Sales Report for "Southeast" Area*

* Sales Report for "Southeast" Area *

Macro variables are stored as character strings. Quotation marks and most special characters are stored exactly as they are assigned, but leading blanks are stripped from assigned values. You can also include references to other macro variables within %LET statements.

Explanation

Macro variables are stored as character strings. Quotation marks and most special characters are stored exactly as they are assigned, but leading blanks are stripped from assigned values. You can also include references to other macro variables within %LET statements.

7. The four types of tokens that SAS recognizes are

Expressions, literals, names, and special characters.

Literals, names, numbers, and special characters.

Expressions, names, numbers, and special characters.

Expressions, literals, numbers, and special characters.

The word scanner recognizes four types of tokens. Expressions are not a type of token.

Explanation

The word scanner recognizes four types of tokens. Expressions are not a type of token.

8. What are the resulting values for the macro variables that are defined here?

%let month1 = June;
%let month2 = July;
%let period1 = &month1&month2;
%let period2 = May&month1;
%let period3 = &month2.Aug;

Month1 June
month2 July
period1 June July
period2 May June
period3 July Aug

Month1 June
month2 July
period1 JuneJuly
period2 MayJune
period3 July.Aug

Month1 June
month2 July
period1 JuneJuly
period2 MayJune
period3 JulyAug

Month1 June
month2 July
period1 junejuly
period2 Mayjune
period3 julyaug

You can combine macro variable references with text to create new text strings. If you precede a macro variable with text, the ampersand at the beginning of the macro variable name signals the end of the text and the beginning of a macro variable name. If you want text to follow the macro variable value, you must signal the end of the macro variable name with a period.

Explanation

You can combine macro variable references with text to create new text strings. If you precede a macro variable with text, the ampersand at the beginning of the macro variable name signals the end of the text and the beginning of a macro variable name. If you want text to follow the macro variable value, you must signal the end of the macro variable name with a period.

9. Which of the following correctly produces a title in which the current date is left justified in order to remove extra blanks?

Title "Report for %sysfunc(left(%sysfunc(today(),worddate.)))";

Title "Report for %sysfunc(left(today(), worddate.))";

Title "Report for %sysfunc(left(%qsysfunc(today(), worddate.)))";

Title "Report for %left(today(), worddate.))";

You use the %QSYSFUNC function in this case, in order to mask the comma that results from the worddate. format. You must mask this comma since the LEFT() function expects only one argument.

Explanation

You use the %QSYSFUNC function in this case, in order to mask the comma that results from the worddate. format. You must mask this comma since the LEFT() function expects only one argument.

10. Which of the following statements will generate an error message while trying to display the value of the macro variable month in the SAS log?

Title "Total Sales for '&month' ";

Title "Total Sales for 'month'";

Title "Total Sales for &month";

Title Total Sales for "&month";

The statement that will generate an error message while trying to display the value of the macro variable month in the SAS log is title "Total Sales for 'month'";. This is because ‘month’ is enclosed in single quotes, which means SAS will interpret it as a literal string, not a macro variable. The other three statements correctly reference month as a macro variable, either enclosed in double quotes or not enclosed in quotes at all.

Explanation

The statement that will generate an error message while trying to display the value of the macro variable month in the SAS log is title "Total Sales for 'month'";. This is because ‘month’ is enclosed in single quotes, which means SAS will interpret it as a literal string, not a macro variable. The other three statements correctly reference month as a macro variable, either enclosed in double quotes or not enclosed in quotes at all.