DO loops in DATA step SAS?

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).

DO loop in SAS Data step example?

SAS Do Loop Example:- data A; do i = 1 to 4; y = i**2; /* values are 2, 5, 9, 16, 25 */ output; end; run; data A; do i = 1 to 4; y = i**2; /* values are 2, 5, 9, 16, 25 */ output; end; run; The END statement marks the end of the SAS loop.

What is macro loop SAS?

These ordinary programming loops iterate during code execution while processing some data elements of an input data table. …

Do Until and do while in SAS?

Do While Loop vs Do Until Explained in SAS

Do Until Executes at Least Once. A fundamental difference between the Do While and Do Until is this:
Do While Evaluates at the Top, Do Until Evaluates at the Bottom.
Do While Executes When Condition is True, Do Until Executes When Condition is False.

Do While loop in SAS macro?

The %DO %WHILE statement tests the condition at the top of the loop. If the condition is false the first time the macro processor tests it, the %DO %WHILE loop does not iterate.

Do loops macro?

A Do Loop statement will have a beginning statement and an ending statement, with the code to perform contained within these two statements. This is like the structure of a macro, where the entirety of a macro code is held inside the Sub statement that starts a macro and the End Sub statement that ends it.

Do loops in SAS examples?

For example, each iteration of the following DATA step increments the value i by 0.5: data A; do i = 1 to 5 by 0.5; y = i**2; /* values are 1, 2.25, 4., 16, 20.25, 25 */ output; end; run; You can also iterate “backwards” by using a negative value for the BY option: do i=5 to 1 by -0.5.

How do you call a macro within a macro in SAS?

You can call a macro within a macro. Here is a trivial example. %macro one(dsn); proc print data=&dsn run; %mend one; %macro two(dslist); %local i; %do i=1 %to %sysfunc(countw(&dslist)); %one(%scan(&dslist,&i)); %end; %mend two; %two(sashelp.

Do loops SAS until?

The DO UNTIL statement executes statements in a DO loop repetitively until a condition is true, checking the condition after each iteration of the DO loop. The DO WHILE statement evaluates the condition at the top of the loop; the DO UNTIL statement evaluates the condition at the bottom of the loop.

How do you break a loop in SAS?

The LEAVE statement in the SAS DATA step is equivalent to the “break” statement. It provides a way to immediately exit from an iterative loop. The CONTINUE statements in the SAS DATA step skips over any remaining statements in the body of a loop and starts the next iteration.

Do loops in SAS?

SAS also supports a DO WHILE and DO UNTIL syntax that does not involve using a counter variable. It is worth noting that a DO loop with an UNTIL clause always executes at least one time because the condition is evaluated at the end of the loop. To prevent this behavior, use a DO loop with a WHILE clause.

DO loops in DATA step SAS?