topic Re: What is the difference between Missover and Truncover? in SAS Programming

What is the difference between Missover and Truncover?

john83 — Fri, 15 Jul 2011 09:19:21 GMT

Hi Guys,

I am new to SAS. I am not able to find any difference between Missover and Truncover.

I have used following example to figure out the difference, but could not found any difference.

DATA test;

INFILE datalines missover;

input lname $ fname $ job $ jobn $;

DATALINES;

LANGKAMM SARAH E0045 Mechanic

TORRES JAN E0029 Pilot

SMITH MICHAEL E0065

LEISTNER COLIN E0116 Mechanic

TOMAS HARALD

WADE KIRSTEN E0126 Pilot

WAUGH TIM E0204 Pilot

;

run;

May be, I have selected wrong example to find the difference. Please help me out to find the difference between the two.

Thanks in advance,

John

What is the difference between Missover and Truncover?

art297 — Wed, 08 Feb 2017 16:28:02 GMT

Although it is subtle, the difference is there:

Use notepad to save the following lines as a text file labeled emplist.txt:

LANGKAMM SARAH E0045 Mechanic
TORRES JAN E0029 Pilot
SMITH MICHAEL E0065
LEISTNER COLIN E0116 Mechanic
TOMAS HARALD
WADE KIRSTEN E0126 Pilot
WAUGH TIM E0204 Pilot

then run the following:

DATA test1;
  INFILE "/folders/myfolders/emplist.txt" missover;
  INPUT lastn $1-21 Firstn $ 22-31
   Empid $32-36 Jobcode $37-45;
RUN;

DATA test2;
  INFILE "/folders/myfolders/emplist.txt" truncover;
  INPUT lastn $1-21 Firstn $ 22-31
   Empid $32-36 Jobcode $37-45;
RUN;

You can find an explanation in the paper at:

http://www2.sas.com/proceedings/sugi26/p009-26.pdf

HTH,

Art

Editor's Note: See also this topic in SAS documentation about MISSOVER, TRUNCOVER, STOPOVER and FLOWOVER.

And this explanation from @Tom:

The difference is what it does when there are not enough characters for the input that you requested.
An easy test is to read in a text file using this input statement.

input line $80. ;

With missover you will get a missing value if the line does not have at least 80 characters (counting trailing spaces). With truncover you get the first 80 characters of the line, even for short lines. Your example works the same with MISSOVER and FLOWOVER because you did not specify a specific number of characters to read in your INPUT statement.

What is the difference between Missover and Truncover?

Cynthia_sas — Fri, 15 Jul 2011 12:56:49 GMT

Hi:

I've always thought this documentation topic was very good:

http://support.sas.com/documentation/cdl/en/basess/58133/HTML/default/viewer.htm#a002645812.htm

It is hard to understand MISSOVER and TRUNCOVER without understanding the default behavior FLOWOVER and this topic also discusses STOPOVER.

cynthia

What is the difference between Missover and Truncover?

Tom — Fri, 15 Jul 2011 17:10:44 GMT

The difference is what it does when there are not enough characters for the input that you requested.

An easy test is to read in a text file using this input statement.

input line $80. ;

With missover you will get a missing value if the line does not have at least 80 characters (counting trailing spaces).

With truncover you get the first 80 characters of the line, even for short lines.

Your example works the same with MISSOVER and FLOWOVER because you did not sepecify a specific number of characters to read in your INPUT statement.

What is the difference between Missover and Truncover?

Ksharp — Mon, 18 Jul 2011 06:14:30 GMT

Just as Art.T said ,the most difference is for column input. And Art.T have a good example.

missover is old product, and truncover is new product, So recommend you to use truncover.

As far as I know pad+missover = truncover

Ksharp

What is the difference between Missover and Truncover?

manojinpec — Mon, 18 Jul 2011 10:55:24 GMT

Thanks all!! i always wondered how to see the difference.I completely understand now.

What is the difference between Missover and Truncover?

john83 — Fri, 22 Jul 2011 07:49:18 GMT

Thank all for your valuable insights and letting me understand the difference between Missover and Truncover.

What is the difference between Missover and Truncover?

MikeZdeb — Fri, 22 Jul 2011 21:41:53 GMT

Hi ... this is a paper that does a very good job explaining various options such as MISSOVER, TRUNCOVER, etc.

MISSOVER, TRUNCOVER, and PAD, OH MY!!

or Making Sense of the INFILE and INPUT Statements.

http://www.nesug.org/proceedings/nesug01/at/at1sa1.pdf

Re: What is the difference between Missover and Truncover?

ChandanaSree — Mon, 29 Jun 2015 12:47:37 GMT

hi sir

Re: What is the difference between Missover and Truncover?

Murali11 — Mon, 14 Aug 2017 00:47:52 GMT

Cynthia,

Thank you very much for your recommendation to review the link to the article that shows differences between TRUNCOVER and MISSOVER. The examples provided hit home the key differences.

Many thanks,

Murali Sastry

Re: What is the difference between Missover and Truncover?

Purnendu — Tue, 19 Sep 2017 08:04:12 GMT

In case missing values in between observation then what should we do? actualy missover is reading only last column missing values.

Can you help me out????

Thanks in advance

Re: What is the difference between Missover and Truncover?

nirupama1 — Fri, 09 Nov 2018 18:13:03 GMT

Hi ,

I used your code which have the positions specified , still I am getting the same result.

I understand the concept of missover and truncover but on practically doing I am not gettng any difference in output.

Both Missover and Truncover are behaving as Truncover.

Honestly, I tried a lot.

Can you please provide an example showing difference in output between these two-missover and truncover.

Will be glad !

Thanks,

Nirupama

Re: What is the difference between Missover and Truncover?

Tom — Fri, 09 Nov 2018 18:17:41 GMT

@nirupama1 wrote:

Hi ,

I used your code which have the positions specified , still I am getting the same result.

I understand the concept of missover and truncover but on practically doing I am not gettng any difference in output.

Both Missover and Truncover are behaving as Truncover.

Honestly, I tried a lot.

Can you please provide an example showing difference in output between these two-missover and truncover.

Will be glad !

Thanks,

Nirupama

Make sure to test using actual files and not in-line data (DATALINES or CARDS statement). SAS will pad in-line data with spaces to a length that is a multiple of 80 characters.

If you still have questions then post the code you tried as a new question.

Re: What is the difference between Missover and Truncover?

nirupama1 — Fri, 09 Nov 2018 18:20:42 GMT

Yes, I was using cards.Thank you! it is really helpful. 🙂