The document discusses the different types of conditional statements in SAS including WHERE, IF, and DO statements. WHERE is used to select observations based on a condition. IF processes observations that meet a condition and can have multiple statements. DO specifies a group of statements to be executed, including do loops that execute statements repetitively until or while a condition is true.

1. Venkata Maguluri

2. Types of conditional statements in SAS:
1) WHERE
a) where “condition”; = where
2) IF
a) if “condition” then “statement”; = if -- then
b) if “condition” then “statement”; else “statement”; = if – then – else
c) if “condition” then “statement”; else if “statement”; = if – then – else -- if
3) DO
a) if “condition” then do; “statement”; end; = if – then – do
b) do while “condition”; “statement”; end; = do while
c) do until “condition” ; “statement”; end; = do until
d) do “var” = “start” to “end”; “statement”; end; = do loop
e) do “var” = “start” to “end” by “inc”; “statement”; end; = do loop
f) do over “array”; “statement”; end; = do loop

3. WHERE conditional statement in SAS:
1) WHERE
a) where “condition”; = where
 It is used to select observations that meet a particular condition in a dataset
 The conditions in where statement can be numeric or character expression
 You can use only one where statement in a data step or in a proc step
Examples:-
/* Selecting observations in a data step */
data dm1;
set derived.dm;
where . < 18 <= age <= 55 and gender=“M”;
run;
/* Selecting observations for processing in a proc step */
proc means data=derived.dm;
where . < age <= 55 and gender=“F”;
run;
http://support.sas.com/documentation/cdl/en/lrdict/61724/HTML/default/a000202951.htm

4. IF conditional statement in SAS:
2) IF
a) if “condition” then “statement”; = if -- then
b) if “condition” then “statement”; else “statement”; = if – then – else
c) if “condition” then “statement”; else if “statement”; = if – then – else – if
 Processes only those observations that meet the condition
 The conditions in if statement can be numeric or character expression
 You can use more than one if statement in a data step
Example:-
data dm1;
set dm;
if citycode=5564 then city=„Mumbai‟ = if -- then
if . < age <= 25 then young=„Yes‟; = if – then – else
else young=„No‟;
if 18 <= age <= 25 then agegrp=‟18 – 25 years‟; = if – then – else – if
else if 26 <= age <= 35 then agegrp=„26 – 35 years‟;
else if 36 <= age <= 45 then agegrp=„36 – 45 years‟;
else agegrp=„> 46 years‟;
run;
http://support.sas.com/documentation/cdl/en/lrdict/61724/HTML/default/a000201978.htm
http://support.sas.com/documentation/cdl/en/lrdict/61724/HTML/default/a000202239.htm

5. DO conditional statement in SAS:
3) DO
a) if “condition” then do; “statement”; end; = if – then – do
b) do while “condition”; “statement”; end; = do while
c) do until “condition” ; “statement”; end; = do until
d) do “var” = “start” to “end”; “statement”; end; = do loop
e) do “var” = “start” to “end” by “inc”; “statement”; end; = do loop
f) do over “array”; “statement”; end; = do loop

6. DO conditional statement in SAS:
1) DO
 The do statement is valid in a data step
 It specifies a group of statements to be executed as a unit
 Every do loop has a corresponding end statement
 The statements between the do and end statements are called a DO group
 You can nest do statements within do groups
 A simple do statement is often used within if – then – else statements to designate a group
of statements to be executed depending on whether the if condition is true or false
 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
 do while statement executes statements in a do loop repetitively while a condition is
true, checking the condition before each iteration of the do loop
 The do until statement evaluates the condition at the bottom of the loop
 The do while statement evaluates the condition at the top of the loop
 do over loop used to perform the operations in the do loop over ALL elements in the array
 Within a single do loop multiple arrays can be referenced and operations on different
arrays can be performed

7.  if “Any Questions” then “Drop me a mail”
else if “NO Questions” then “Comment below”

 if “Any Questions” then
do “Ask and Drop me a mail”
end
else if “NO Questions” then “Leave your comment” 