Muito obrigado Augusto. <div><br></div><div>Era isso mesmo que eu precisava.</div><div><br></div><div>Só mais uma coisa, como eu faço para não listar o vetor com TRUE e FALSE depois do comando <span style="font-family:Verdana,Geneva,Helvetica,Arial,sans-serif;font-size:13px;background-color:rgb(255,255,255)">duplicated(dados$codigo)?</span></div>
<div><font face="Verdana, Geneva, Helvetica, Arial, sans-serif"><br></font></div><div><font face="Verdana, Geneva, Helvetica, Arial, sans-serif"><br></font><div><br></div><div><br><br><div class="gmail_quote">Em 2 de outubro de 2012 15:26, Carlos Mendonça <span dir="ltr"><<a href="mailto:csaeslpv@centroin.com.br" target="_blank">csaeslpv@centroin.com.br</a>></span> escreveu:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div>Prezados,</div><div><br></div><div>tenho um arquivo tradutor com várias observações para um mesmo código.</div><div>
<br></div><div>Preciso ficar só com a primeira<span> <span>observação</span> </span>de cada código desse arquivo tradutor. Como posso fazer isto?</div>

<div><br></div><div><b>Arquivo tradutor</b></div><div><br></div><div><div class="gmail_quote"><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">


<div style="font-size:13px;font-family:Verdana,Geneva,Helvetica,Arial,sans-serif"><div>codigo<span style="white-space:pre-wrap">  produto 1  </span>       valor3</div><div>a<span style="white-space:pre-wrap">        </span>             3<span style="white-space:pre-wrap">  </span>                  25<span style="white-space:pre-wrap">    </span>                           </div>


<div>a<span style="white-space:pre-wrap"> </span>             5<span style="white-space:pre-wrap">  </span>                  10<span style="white-space:pre-wrap">    </span>                            </div><div>a<span style="white-space:pre-wrap">    </span>             2<span style="white-space:pre-wrap">  </span>                  15<span style="white-space:pre-wrap">    </span>                            </div>


<div>b<span style="white-space:pre-wrap"> </span>           15<span style="white-space:pre-wrap">   </span>                  85<span style="white-space:pre-wrap">    </span>                            </div><div>b<span style="white-space:pre-wrap">    </span>             5<span style="white-space:pre-wrap">  </span>                  15<span style="white-space:pre-wrap">    </span>                            </div>


<div>c<span style="white-space:pre-wrap"> </span>             2                     5<span style="white-space:pre-wrap">    </span>                            </div><div>c<span style="white-space:pre-wrap">    </span>             4<span style="white-space:pre-wrap">  </span>                    7<span style="white-space:pre-wrap">   </span>                              </div>


<div>c<span style="white-space:pre-wrap"> </span>             2                     5<span style="white-space:pre-wrap">    </span>                             </div><div>c<span style="white-space:pre-wrap">   </span>             2<span style="white-space:pre-wrap">  </span>                    3<span style="white-space:pre-wrap">   </span>             </div>


</div></blockquote><div><br></div><div><br></div><div><b>Resultado desejado </b></div><div><br></div><div><div style="font-family:Verdana,Geneva,Helvetica,Arial,sans-serif;font-size:13px">codigo<span style="white-space:pre-wrap">   produto 1  </span>       valor3</div>


<div style="font-family:Verdana,Geneva,Helvetica,Arial,sans-serif;font-size:13px">a<span style="white-space:pre-wrap">  </span>             3<span style="white-space:pre-wrap">  </span>                  25<span style="white-space:pre-wrap">    </span>                           </div>


<div style="font-family:Verdana,Geneva,Helvetica,Arial,sans-serif;font-size:13px">b<span style="white-space:pre-wrap">  </span>           15<span style="white-space:pre-wrap">   </span>                  85<span style="white-space:pre-wrap">    </span>                            </div>


<div style="font-family:Verdana,Geneva,Helvetica,Arial,sans-serif;font-size:13px">c<span style="white-space:pre-wrap">  </span>             2                     5<span style="white-space:pre-wrap">    </span>                            </div>


<div style="font-family:Verdana,Geneva,Helvetica,Arial,sans-serif;font-size:13px">    </div></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left-width:1px;border-left-color:rgb(204,204,204);border-left-style:solid;padding-left:1ex">


<div style="font-size:13px;font-family:Verdana,Geneva,Helvetica,Arial,sans-serif"><div>               </div><div><br></div></div></blockquote></div></div><div><br></div>
</blockquote></div><br><br clear="all"><div><br></div>-- <br><div>                Um abraço,</div>
<div> </div>
<div>                Carlos Mendonça.</div><br>
</div></div>