topic Re: Difference between strip, compress and trim in SAS Programming

What is the difference between strip, compress and trim?

pooja215 — Fri, 04 Jun 2021 20:43:10 GMT

Hi ,

Could you tell me which function i cannot use for removing leading and trailing spaces from a character text?

Regards,

Pooja.

Re: Difference between strip, compress and trim

LinusH — Mon, 09 Jan 2017 08:53:08 GMT

The documentation is quite clear IMO. What is your doubt?

This can be quite easily tested by using hard coded string in a data step, with comparisons/putting using $HEX. format.

Re: Difference between strip, compress and trim

pooja215 — Mon, 09 Jan 2017 08:58:07 GMT

Thanks for such an early response!
Which of the following cannot be used to "just" remove the leading and trailing spaces from character data?

* Strip

* Compress

* Trim
Regards,
Pooja.

Re: Difference between strip, compress and trim

PeterClemmensen — Mon, 09 Jan 2017 09:12:53 GMT

data test;
   string = '    AB C D  ';

   strip_var    = strip(string);
   compress_var = compress(string);
   trim_var     = trim(string);
run;

Re: Difference between strip, compress and trim

Shmuel — Tue, 27 Jun 2017 12:34:41 GMT

Run next code and learn the result of each function:

data _null_;
    length text $15;
    format text $char15.;
    text = '  ab   cde  f   ';
    trim = '*'||trim(text)||'*';
    compress = '*'||compress(text)||'*';
    strip = '*'||strip(text)||'*';
    put trim= ;
    put compress= ;
    put strip=;
run;

Here's the output:

trim=*  ab   cde  f*
compress=*abcdef*
strip=*ab   cde  f*

Re: Difference between strip, compress and trim

pooja215 — Mon, 09 Jan 2017 09:31:43 GMT

Thanks it really helped!!

Re: Difference between strip, compress and trim

RW9 — Mon, 09 Jan 2017 09:52:21 GMT

And what does the manual say? This is not a "question" as such, but asking someone to repeat what is clearly written in the manual. I will paste tehm below for you:

Strip:

http://support.sas.com/documentation/cdl/en/lrdict/64316/HTML/default/viewer.htm#a002295689.htm

Trim:

http://support.sas.com/documentation/cdl/en/lrdict/64316/HTML/default/viewer.htm#a000212226.htm

Compress:

http://support.sas.com/documentation/cdl/en/lrdict/64316/HTML/default/viewer.htm#a000212246.htm

Each page actually gives you examples of the use of each of them. And links to other string compress/stripping functions which may be of use.

Re: Difference between strip, compress and trim

Patrick — Mon, 09 Jan 2017 10:37:33 GMT

@pooja215

I guess this was in interview question. So now with all the information you've got, what would be your answer and why?

Re: Difference between strip, compress and trim

pooja215 — Mon, 09 Jan 2017 10:43:43 GMT

It wasn't an interview question. I got the information about trim, strip and compress in more detail.
The answer to my question was trim, as it did not remove the leading space from my text.
Regards,
Pooja.

Re: Difference between strip, compress and trim

Patrick — Mon, 09 Jan 2017 10:53:29 GMT

If you're using the question as you've formulated it the 2nd time "Which of the following cannot be used to "just" remove the leading and trailing spaces from character data?" then also compress() couldn't get used as it removes ALL blanks and not only the leading and trailing ones.

The two ways that's normally done:

strip(<string>)

trim(left(<string>))