topic Re: Help with prxchange in SAS Programming

Help with prxchange

Maurits — Thu, 31 Aug 2017 12:57:34 GMT

I have a dataset with a char variable containing the following example values:

AA1

AA2a

AA10

AA11a

BB3

BB3b

BB10

BB11b

Essentially I want to zero-pad the numeric part of each value (e.g. 'AA2a' becomes 'AA02a') and thought the prxchange function would be a quick and simple way of achieving this. However, the problem I have run into is how to reference the zero in the replacement text.

So far the code is similar to:

var2 = prxchange('s/^(\w{2})(\d{1})(\D?)$/$1$2$3/', -1, trim(var1));

How do I reference (and delimit) the zero character in the replacement string of the prxchange function ($1 ->0<- $2$3)?

Re: Help with prxchange

Maurits — Thu, 31 Aug 2017 13:04:46 GMT

Never mind, I've managed to find the solution whilst scrawling the interweb!

For those that are interested... use the perl metacharacter \Q which escapes all non-word characters.

So, the code becomes:

var2 = prxchange('s/^(\w{2})(\d{1})(\D?)$/$1\Q0$2$3/', -1, trim(var1));

Re: Help with prxchange

Ksharp — Thu, 31 Aug 2017 13:46:13 GMT

data have;
input x $;
y=prxchange('s/^([a-z]+)(\d)([a-z]*)$/\10\2\3/i',1,strip(x));
cards;
AA1
AA2a
AA10
AA11a
BB3
BB3b
BB10
BB11b
;
run;

Re: Help with prxchange

Maurits — Thu, 31 Aug 2017 13:53:17 GMT

Thanks for the reply Ksharp but your proposal wouldn't work as the prxchange function would look for the input buffer "\10".

Re: Help with prxchange

Ksharp — Fri, 01 Sep 2017 12:15:43 GMT

But there are only three buffer.
Did you run my code and see the output?

or try   $10