topic Re: Creating variable conditional on string part in SAS Data Management

Creating variable conditional on string part

ilikesas — Wed, 24 Dec 2014 16:10:19 GMT

Hi,

suppose I have the following table:

company
ABC (delisted in 1/1/2010)
DEF

Is it possible to get the following:

company	delist
ABC (delisted in 1/1/2010)	yes
DEF	no

That is, if in the company's name the word "delisted" is present, I would like to have a new column that says "yes", and if the company wan't delisted, then "no" will appear

Thank you

Re: Creating variable conditional on string part

Haikuo — Wed, 24 Dec 2014 16:27:19 GMT

Please read Docs on FIND(), FINDW(), INDEX, INDEXW(), COUNT() or you want something spicier, PRXMATCH().

If you use Proc SQL, you can also explore CONTAINS or LIKE clause.

Good luck,

Haikuo

Re: Creating variable conditional on string part

Ksharp — Thu, 25 Dec 2014 08:12:25 GMT

data have;

input x & $40.;

if prxmatch('/$.*$/',x) then found=1;else found=0;

cards;

ABC (delisted in 1/1/2010)

DEF

;

run;

Xia Keshan

Re: Creating variable conditional on string part

ilikesas — Fri, 02 Jan 2015 00:40:22 GMT

Hi Xia Keshan,

Thank you for the code, I did it and it worked.

I was just wandering, in your code the prxmatch is looking for parentheses, but if I do have for some company parentheses like this:

CompABC (public 2007)

Then found will be 1 for this as well, so what I did is the following:

if prxmatch("/delisted /",company) then found=1;else found=0;

I ran the code on a small sample and it seems to be working.

Thank you and a happy new year!

Re: Creating variable conditional on string part

Patrick — Fri, 02 Jan 2015 01:03:31 GMT

I love regular expressions but in your case I would use a simple findw() function.

With a RegEx I would use the 'i' switch so the search pattern is not case sensitive and I would use the \b metacharacter to only find "delisted" if it's a word on it's own.

data have;

input x & $40.;

if findw(x,'delisted','( ','i') then found1=1; else found1=0;

if prxmatch('/\bdelisted\b/oi',x) then found2=1;else found2=0;

cards;

ABC (delisted in 1/1/2010)

DEF

CompABC (public 2007)

;

run;

Re: Creating variable conditional on string part

ilikesas — Sun, 04 Jan 2015 01:37:37 GMT

Hi Patrick,

thank you for your code, I ran it and obtained what I wanted.

I would like to ask you something else if I may:

If a given company was delisted, how to create another column which will contain the date when the company was delisted?

Thank you

Re: Creating variable conditional on string part

Ksharp — Sun, 04 Jan 2015 05:44:01 GMT

Here is :

data have;
  input x & $40.;
  if prxmatch('/\bdelisted\b/oi',x) then do;
     found2=1;
      date=prxchange('s/.*(\d+\/\d+\/\d+).*/$1/oi',-1,x);
      end;
else found2=0;
  cards;
ABC (delisted in 1/1/2010)
DEF
CompABC (public 2007)
;
run;

Xia Keshan

Re: Creating variable conditional on string part

ilikesas — Sun, 04 Jan 2015 18:47:10 GMT

Hi Xia Keshan,

Thank you for your code!!!

What I especially find interesting is that it will give me the date even if I have something like this:

ABC (delisted in 1/1/2010 33.AA)

I guess that this is because the prxchange function, with the arguments you gave it, is searching for the first from the left string element that is in the date form as specified by the argument.

Thank you!

Re: Creating variable conditional on string part

Ksharp — Mon, 05 Jan 2015 06:00:06 GMT

That is a big advantage of Perl Regular Expression than the SAS function. I would prefer to use PRX firstly , then after that considering about SAS function.