Question: How Do You Keep Variables In SAS?

How do I drop observations in SAS?

To remove observations in SAS, you can use the IF statement in a DATA step.

Suppose you want to exclude all observations whose scores are greater than 100..

What is a categorical variable in SAS?

Variables which record a response as a set of categories are termed categorical. Such variables fall into three classifications: Nominal, Ordinal, and Interval. Nominal variables have categories that have no natural order to them.

How do you make a variable numeric in SAS?

Convert character to numeric. To convert character values to numeric values, use the INPUT function. new_variable = input(original_variable, informat.); The informat tells SAS how to interpret the data in the original character variable.

How do you input data into SAS?

dat into SAS, use the following syntax: DATA cars4; INFILE “c:carsdatacars4. dat”; INPUT make $ model $ mpg weight price; RUN; TITLE “cars4 data”; PROC PRINT DATA=cars4(OBS=5); RUN; Here is the output produced by the proc print statement above.

How do I declare a variable in SAS?

You can create variables in a DATA step in the following ways:by using an assignment statement.by reading data with the INPUT statement in a DATA step.by specifying a new variable in a FORMAT or INFORMAT statement.by specifying a new variable in a LENGTH statement.by specifying a new variable in an ATTRIB statement.

What does set mean in SAS?

SET reads an observation from an existing SAS data set. INPUT reads raw data from an external file or from in-stream data lines in order to create SAS variables and observations. Using the KEY= option with SET enables you to access observations nonsequentially in a SAS data set according to a value.

What is a SAS variable?

Variable types In SAS, there are two types of variables: numeric and character. Numeric variables are variables that store numbers. … Missing values for numeric variables appear as a period (.). Character variables (also known as string variables) contain information that the system recognizes as text.

How do you subset observations in SAS?

Subsetting a SAS data set means extracting a part of the data set by selecting a fewer number of variables or fewer number of observations or both. While subsetting of variables is done by using KEEP and DROP statement, the sub setting of observations is done using DELETE statement.

How do you delete a variable in SAS?

To delete variables in SAS, you can use the DROP statement in a DATA step. Suppose you want to delete variables x1 , x2 , and x3 in SAS data set old1 and save it to a new SAS data set new1 .

How do you rename variables in SAS?

There may be occasions in which you want to change some of the variable names in your SAS data set. To do so, you’ll want to use the RENAME= option. As its name suggests, the RENAME= option allows you to change the variable names within a SAS data set. RENAME = (old1=new1 old2=new2 ….

How do you drop multiple variables in SAS?

In DATA steps, when you create multiple output data sets, use the DROP= data set option to write different variables to different data sets. The DROP statement applies to all output data sets. In PROC steps, you can use only the DROP= data set option, not the DROP statement.

How do you delete a macro variable in SAS?

Deleting Macro VariablesGood house keeping demands that we throw away things when we no longer need them, such as data sets and variables. … In 8.2 CALL SYMDEL allows us to delete macro variables from the macro global symbol table:%let mvar998 = Another macro variable;%let mvar999 = Yet another macro variable;data _null_;More items…

Do loop SAS data step?

Iterative DO loops are the simplest form of DO loops that can be executed within a SAS Data Step. The actions of an iterative DO loop are unconditional, meaning that if you define a loop to execute 50 times, it will execute 50 times without stopping (unless an error occurs during processing).

What is keep in SAS?

The KEEP statement causes a DATA step to write only the variables that you specify to one or more SAS data sets. The KEEP statement applies to all SAS data sets that are created within the same DATA step and can appear anywhere in the step. … Note: Do not use both the KEEP and DROP statements within the same DATA step.

How does retain work in SAS?

In the most general terms, the RETAIN statement is used to keep (retain) values from one observation to the next during iterations of the SAS Data Step. … The RETAIN statement overrides this default behaviour, and retains the value from the previous observation before completing the next iteration of the Data Step.

How does SAS process data?

The Process. When you submit a DATA step for execution, SAS automatically compiles the DATA step and then executes it. At compile time, SAS creates the input buffer, program data vector, and descriptor information for the data set WEIGHT_CLUB.

What is Proc step SAS?

A group of SAS procedure statements is called a PROC step. The PROC step consists of the following: a beginning procedure (PROC) statement with options. typically, statements specifying plot types, variables, and options. an ending RUN statement.

How do I delete a row in SAS dataset?

To delete some or all of the rows in a table, use the DELETE statement. When the statement is successfully executed, the SAS log shows a message that indicates the number of rows that have been deleted. WHERE is optionally used to specify an expression that subsets the rows to be deleted.

What is the purpose of using an IF condition then delete statement in a data step?

IF-THEN-DELETE Statement Use the DELETE statement when it is easier to specify a condition that excludes observations from the data set or when there is no need to continue processing the DATA step statements for the current observation. Do not confuse the DROP statement with the DELETE statement.

How do you use first variable in SAS?

When an observation is the first in a BY group, SAS sets the value of FIRST. variable to 1 for the variable whose value changed, as well as for all of the variables that follow in the BY statement. For all other observations in the BY group, the value of FIRST. variable is 0.