This tutorial explains how to extract last n characters or numbers of a variable in SAS. In this tutorial, we will cover several cases in which we pull last 4 character or numeric values from a column. In MS Excel, it is easily possible with RIGHT() function but there is no-inbuilt function to do it in SAS. The RIGHT() function of SAS is used for something else i.e. it right aligns string or character value.
Example 1
Suppose you have a product ID in which last 4 characters refers to a product category so you are asked to pull product category information.
The output is shown in the image below -
Explanation
Example 2 : Handle missing while extracting
Suppose you have multiple product IDs in which some of them are missing.
To workaround this problem, we can use SUBSTRN() which handles missing cases while extracting.
Suppose product ID variable is numeric.
Another Method -
Step 1 : LOG10(1021) returns 3.009
Step 2 : INT(LOG10(1021)) makes it 3
Step 3 : Adding 1 to step2 makes it 4, which is result of number of digits in 1021.
Example 1
Suppose you have a product ID in which last 4 characters refers to a product category so you are asked to pull product category information.
data example;
productID = "AB123ZX253";
run;
data example;
set example;
referenceid = substr(productID,length(productID)-3,4);
run;
The output is shown in the image below -
 |
| Get last N Characters |
The SUBSTR() function returns sub-string from a character variable.
= SUBSTR(character-variable, beginning-position, number-of-characters-to-pull)The LENGTH() function returns the length of a character variable. In this case, it is 10 characters long. The calculated SUBSTR() function would work like below -
= SUBSTR(productID, 10-3, 4)
= SUBSTR(productID, 7, 4)
Example 2 : Handle missing while extracting
Suppose you have multiple product IDs in which some of them are missing.
data example2;When you apply SUBSTR() function in case of missing cases, it returns a note in log 'Invalid second argument'. See the image below
input productID $10.;
cards;
AB123ZX253
AB123ZX254
AB123ZX255
;
run;
 |
| SUBSTR : Missing Cases |
data example2;Example 3 : Get last N digits from a numeric variable
set example2;
referenceid = substrn(productID,length(productID)-3,4);
run;
Suppose product ID variable is numeric.
data example3;The SUBSTR() / SUBSTRN() function works only for character variables. In order to make it run for numeric variables, we first need to convert numeric variables to character variables with PUT() function.
input productID;
cards;
12345253
12354234
12354235
;
run;
data example3;Since SUBSTRN() returns character variable, we need to convert it to numeric with INPUT() function.
set example3;
x = put(productID, 10.);
referenceid = input(substrn(x,length(x)-3,4),8.);
drop x;
proc print noobs;
run;
Another Method -
data example3;How it works -
set example3;
referenceid = input(substrn(productID,INT(LOG10(productID))+1-3,4),8.);
proc print noobs;
run;
Step 1 : LOG10(1021) returns 3.009
Step 2 : INT(LOG10(1021)) makes it 3
Step 3 : Adding 1 to step2 makes it 4, which is result of number of digits in 1021.
About Author:
Deepanshu founded ListenData with a simple objective - Make analytics easy to understand and follow. He has over 10 years of experience in data science. During his tenure, he has worked with global clients in various domains like Banking, Insurance, Private Equity, Telecom and Human Resource.
This was very useful. Thanks so much!
ReplyDeletebut ..when numeric variable when used in character function ..implicit conversion from numeric to character happen ....why convert explicitly with put statement.
ReplyDeleteHow can we find last position of two digit number
ReplyDeletecould anyone explain the meaning of -3.
ReplyDeleteSecond parameter in SUBSTR() refers to starting position. In the first example, it returns 7 after subtracting 3 from productID. End result would return 7th, 8th, 9th and 10th character. In total it returns last 4 characters.
Delete-3 becoz we want last 4 digit so when we are doing lenght(productID) it gives 10 and 10-3 gives 4 that's why there is -3.
DeleteIt gives the result from right to left
Deletewhat if you have different lengths of a variable? in that case , how will you extract last 4 characters
DeleteIf we want last 4 characters, then we would want the substr()'s second argument be the fourth character's position from right to left, which is the length of the string - 3; If we want the last 5, then it should be the length - 4.
DeleteCan I use substr (, -1,4) for getting last 4 characters?
ReplyDeleteNO
Deletewhat if the input variables has different length and we have to extract some characters from the string of different length
ReplyDeleteCan anyone answer how can I output the date in YYYY-MM-DD format if I have diferent tipe of dates?
ReplyDeleteExample
17.Jan/2013
13-11-14
3/12/16
January 16 2019
16 feb 2020
haha i think recently u attend interview for hcl screening round
Deletebrother u got answer or not
Deleteplease let us know
data have;
Deleteinput char_date : $20. fmt : $20.;
num_char=inputn(char_date,fmt);
format num_char date9.;
cards;
12-08-2015 DDMMYY12.
12/8/2016 MMDDYY12.
05/25/2015 MMDDYY12.
;
run;
proc print;run;
how do i get the position for a numeric value?
ReplyDeleteI HAVE NEED FRIST FOUR STRINGS OF FRIST SPACE
ReplyDeletedata ab;
ReplyDeleteinput var1 var2 var3 var4 var5 var6 var7 var8 var9 var10;
cards;
1 2 3 4 5 6 7 8 9 10
run;
how can we convert the above 10 numeric varianbles into character variables by using arrays?
data ink2;
ReplyDeleteinput joindate;
informat joindate :anydtdte.;
cards;
17.Jan/2013
13-11-14
3/12/16
january 16 2019
16feb2020
;
proc print;
run;
can anyone answer this query am facing error
data ink2;
Deleteinput joindate:anydtdte;
cards;
17.Jan/2013
13-11-14
3/12/16
january 16 2019
16feb2020
;
proc print;
run;
pradeep.malegave123@yahoo.com in this mail id how can i extract my last name. ie malegave. Please give solution in base sas.
ReplyDelete