st: generating a new numerical variable3 using a string variable2 which is nested in a numerical variable1

[José Maria <jmpsouza@usp.br>]

Dear Statalisters:
sorry for so long a  name in the subject.
   I need to generate a  variable3 which  is the numerical identification 
of a string  variable2, that is nested in alphabetical order in a numerical 
variable1. The final result would be something like
var1 (already exist)       var2 (already exist)    var3 (to be generated)
1                                    a                                    1
1                                    a                                    1
1                                    a                                    1
1                                    b                                    2
2                                    m                                   1
2                                    m                                   1
2                                    n                                    2
2                                    n                                    2
2                                    p                                    3
3                                    c                                    1
3                                    c                                    1
3                                    c                                    1
3                                    c                                    1
   Thanks for any help.

José Maria

Jose Maria Pacheco de Souza, Professor Titular (aposentado)
Departamento de Epidemiologia/Faculdade de Saude Publica, USP
Av. Dr. Arnaldo, 715
01246-904  -  S. Paulo/SP - Brasil
fones (11)3061-7747; (11)3768-8612;(11)3714-2403
www.fsp.usp.br/~jmpsouza 


__________ Informação do ESET NOD32 Antivirus, versão da vacina 4607 (20091114) __________

A mensagem foi verificada pelo  ESET NOD32 Antivirus.

http://www.eset.com



*
*   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/