topic Re: Efficient way to extract words from text and place in new variable in SAS Programming

Efficient way to extract words from text and place in new variable

Caetreviop543 — Wed, 04 Mar 2020 21:34:35 GMT

I'm trying to figure out the best, most succinct way to extract words from a text variable, and place them in a new variable. I have a text variable:

TXT

Some text

More text

List text

Read text

And I want to extract certain words from TXT and create a new variable:

TXT Extract

text Some Some

More text More

text word List List

Read text Read

So far this is the only code I came up with:

data new;
set old;

if find(TXT, "Some")>0 then Extract = "Some";
else if find(TXT, "More")>0 then Extract = "More";
else if find(TXT, "List")>0 then Extract = "List";
else if find(TXT, "Read")>0 the Extract = "Read";

run;

It works, but is pretty clunky. Does anyone know a better way?

Re: Efficient way to extract words from text and place in new variable

novinosrin — Wed, 04 Mar 2020 21:32:48 GMT

Extract=scan(txt,1,' ');

Re: Efficient way to extract words from text and place in new variable

Caetreviop543 — Wed, 04 Mar 2020 21:35:05 GMT

I made the example too simple; the word I want to extract isn't always the first.

Re: Efficient way to extract words from text and place in new variable

novinosrin — Wed, 04 Mar 2020 21:38:28 GMT

Oops sorry I overlooked completely. my apologies

Re: Efficient way to extract words from text and place in new variable

Caetreviop543 — Wed, 04 Mar 2020 21:45:19 GMT

That's ok! I should have made the example better.

Re: Efficient way to extract words from text and place in new variable

novinosrin — Wed, 04 Mar 2020 21:55:08 GMT

HI @Caetreviop543 Would this come close?

Basically, eliminating the word 'text' in the string

data have;
input TXT & :$10. ;
cards;

Some text

More text

List text

Read text
text red
;

data want;
 set have;
 temp=strip(tranwrd(txt,'text',' '));
run;

Re: Efficient way to extract words from text and place in new variable

Caetreviop543 — Wed, 04 Mar 2020 21:59:47 GMT

Thanks for your response. Is there a way to extract just the word if the text isn't all the same, i.e., the actual word text doesn't appear throughout? I just used text to symbolize a string of words.

Re: Efficient way to extract words from text and place in new variable

novinosrin — Wed, 04 Mar 2020 22:03:48 GMT

Is there a way to extract just the word if the text isn't all the same,

By the above, do you mean you only want to extract a set of known words? Like as though you have a list of words to extract from the string???Please clarify

@Caetreviop543 wrote:

Thanks for your response. Is there a way to extract just the word if the text isn't all the same, i.e., the actual word text doesn't appear throughout? I just used text to symbolize a string of words.

Re: Efficient way to extract words from text and place in new variable

ChrisNZ — Wed, 04 Mar 2020 22:05:10 GMT

You can write this in a more compact manner, but it is less legible.

EXTRACT = prxchange('s/.*(Some|More|List|Read).*/\1/',-1,TXT);

This means: find anything then one of the strings then anything else and replace with the string found.

Re: Efficient way to extract words from text and place in new variable

Caetreviop543 — Wed, 04 Mar 2020 22:09:23 GMT

It told me the prxchange argument doesn't have enough arguments. How does it know which variable to change/extract words from?

Re: Efficient way to extract words from text and place in new variable

ChrisNZ — Wed, 04 Mar 2020 22:11:06 GMT

Try again, I corrected within seconds . I clicked too fast and you are too fast. 🙂

Re: Efficient way to extract words from text and place in new variable

ChrisNZ — Wed, 04 Mar 2020 22:15:23 GMT

1 is probably fine rather than -1 actually. Sorry I can't test.

Re: Efficient way to extract words from text and place in new variable

Caetreviop543 — Wed, 04 Mar 2020 22:16:31 GMT

Thanks, but that didn't work. It returned a much larger list of lots of text.

Re: Efficient way to extract words from text and place in new variable

ChrisNZ — Wed, 04 Mar 2020 22:44:36 GMT

Mmm that's odd. I probably forgot something obvious. I can't test sadly.

Re: Efficient way to extract words from text and place in new variable

novinosrin — Wed, 04 Mar 2020 22:48:11 GMT

Hi @Caetreviop543 For hard coded char constants, you could consider a fast approach which is merely tweak of your original. See if this helps


data have;
input TXT & :$10. ;
cards;

Some text

More text

List text

Read text
text red
;

data want;
 set have;
 array t(5) $32 _temporary_ ('Some' 'More' 'List' 'Read' 'red') ;
 length extract $32;
 do _n_=1 to dim(t) until(not missing(extract));
  if index(txt,strip(t(_n_))) then extract=t(_n_);
 end;
run;

Re: Efficient way to extract words from text and place in new variable

Caetreviop543 — Wed, 04 Mar 2020 23:09:00 GMT

Thanks that worked!!