Adding zeros in front of values

[JediApprentice]

I have a dataset with values like this (it is a character with length of 7)

What I want is this - IF the actual value is less than 5 digits, add zeros to the beginning of the value until it is 5 digits long. 

[novinosrin]

data want;

set have;

if length(var)<5 then var=reverse(substr(strip( reverse(var))||'00000000',1,5) ); 

run;

Regards,

Naveen Srinivasan

[Astounding · Accepted solution]

A simple loop could do it:

do while (length(var) < 5);

   var = '0' || var;

end;

[bollurajkumar]

hi

the

variable is numeric so use formate option

DATA test_data1; 
input studyid ; 
format studyid z8.; 
cards;
543
243
15967
26484143651
5442
124
1
23
4423
;
run;

formate zw.

w means total how many digits you want with zeros

[JediApprentice]

@Astounding How exactly does this work? How is the data step looping back to keep adding zeros - I get that there's the while condition, but say I have 123 which needs  2 zeros in front of it. Data step will go through the loop to put the first 0 in front. How does it come back to that observation to add another zero? I know it has to do with the condition and the PDV, just not sure of the details...

[Astounding]

It's the logic of DO WHILE.

After the first time through the loop a single zero has been added:  0123

The DO WHILE condition is still true, since the length is now 4.  So the loop executes a second time, adding another zero:  00123

Now the DO WHILE condition is false, so the loop ends.

[thomp7050]

DATA test_data1; 
length studyid $50;
input studyid $;  
cards;
543
243
15967
26484143651
5442
124
1
23
4423
;
run;

data test_data1;
set test_data1;
if length(studyid) < 5 THEN DO;
studyid = repeat('0',5-length(studyid)) || studyid;
END;
run;