/*** TIP 00400 ***/
 Match String Patterns

 I have a field which mixes addresses, cities and postal code etc. Is
 there any function or method that I can use to find out the only the
 postal code(a string pattern)?

 eg.

 Apt 16
 123 any street
 3456 any Ave.
 M5E 7B7 <-----needs to be identified
 L2T 9Y1 <-----needs to be identified
 New York
 Toronto

Solution provided by David Cassell
Cassell.David@epa.gov

If you have SAS 9.x , I suggest you look at the PRX... functions.

It looks as if you want the following form:

^      start of field
\s*    (maybe with whitespace at the front)
[A-Z]  a letter from A to Z
\d     a digit
[A-Z]  A to Z again
       a space
\d     a digit
[A-Z]  A to Z again
\d     a digit
\s*    possible whitespace
$      end of field


So try the following code:

data new;
  set YourData;
  if _n_=1 then do;
    re = prxparse('/^\s*[A-Z]\d[A-Z] \d[A-Z]\d\s*$/');
    if missing (re) then stop;
  end;

  if prxmatch(re,YourNameField);
  run;

This ought to pull out the desired records.
/*** end of tip 00400 ***/