Re: st: Fwd: Fastest way to identify values that start and end with a 9?

[David Kantor <kantor.d@att.net>]

> On Thu, 3 Oct 2013, Evan DeFilippis wrote:
>
> > Values in my data set contain different numerical representations for
> > "Don't Know" and "Refusal"
> >
> > A "Don't Know" will always start and end with a '9', but there can be
> > as many '9's in between as possible, up to the maximum length of a
> > string (244).
> >
> > A "Refusal" will always start with a '9' and end with an '8', and
> > there can be as many '9's' in between as possible, up to the maximum
> > length of a string (244).

I haven't been following this from the beginning, but it strikes me 
as similar to a situation that I have dealt with in the past -- and I 
have code to deal with it (available, if you like).
My handling of the situation always...
1, requires a knowledge of the maximal number of digits for each 
particular variable. That requires knowing some facts about the 
encoding of each variable -- either from documentation or from 
examining the data. Thus, if you specify 4 digits, the code looks for 
values 9998 and 9999. In this case, for example, you would want to 
recode 9998 to REF, but leave 998 as a legitimate value.
2, leaves the type as numeric (integer), and uses extended missing 
values to represent the DK and REF values. (You can assign a value 
label to cover these values.)

HTH
--David

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