Re: st: identification of particular string formats

[Jamie Fagg <j.fagg@ich.ucl.ac.uk>]

Dear Nick,

Many thanks for your reply and your time. This has solved my problem and 
also given me some helpful avenues for further exploration.

Jamie

On 05/05/2011 18:18, Nick Cox wrote:
> Note for U.S. and some other readers: the reference is to British postcodes.
>
> I'd class this problem as one of counting _distinct_ values --
> although many people would say _unique_ values. There is a review at
>
> SJ-8-4  dm0042  . . . . . . . . . . . .  Speaking Stata: Distinct observations
>          (help distinct if installed)  . . . . . .  N. J. Cox and G. M. Longton
>          Q4/08   SJ 8(4):557--568
>          shows how to answer questions about distinct observations
>          from first principles; provides a convenience command
>
> Using the command in question
>
> . distinct postcode if length(postcode) == 3
>
> . distinct postcode if !strpos(postcode, " ")
>
> are solutions. In fact -tab postcode- with the -if- conditions will
> count too, although the count is returned silently in r(r).
>
> Nick
>
> On Thu, May 5, 2011 at 6:07 PM, Jamie Fagg<j.fagg@ich.ucl.ac.uk>  wrote:
>
> > Specification: Stata version 11.1, Windows XP
> >
> > I have a list of postcodes. I'd like to be able to count ones which have a
> > certain format. For example, from the following list, I'd like to know that
> > there are 2 postcodes with only 3 characters,
> > and 2 which have no central blank. A search of the archives hasn't helped,
> > mainly because I feel I'm not searching correctly.
> >
> > My question is therefore, for this specific example, how would I count and
> > list the postcodes in question.
> >
> > B30
> > B31
> > B30 1AH
> > B30 1NH
> > B30 1XB
> > B303RB
> > B312QH
> > B31 2QH
> > B31 5AX
> > B32 1NL
> > B32 1PL
> *
> *   For searches and help try:
> *   http://www.stata.com/help.cgi?search
> *   http://www.stata.com/support/statalist/faq
> *   http://www.ats.ucla.edu/stat/stata/

--
MRC Centre of Epidemiology for Child Health
UCL Institute of Child Health
30 Guilford Street
London, WC1N 1EH

Tel - 0207 905 2320

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/