Não complique o fácil!!<br><br>da=data.frame(A=rep(LETTERS[1:3],3),<br><div id=":1vt">                      B=rep(letters[1:3],3),<br>                      y=rnorm(9),<br>                      x=rnorm(9),<br>                      z=rnorm(9))<br>

<br>aggregate(da[,-c(1:2)], <br>               list(A=da[['A']],<br>                    B=da[['B']]),<br>               function(x) c('Média'=mean(x), <br>                                  'Desvio'=sd(x),<br>

                                  'CV'=sd(x)/mean(x)*100))<br><br>(S,f,P)<div class="yj6qo ajU"><div id=":1us" class="ajR" tabindex="0"><img class="ajT" src="https://mail.google.com/mail/u/0/images/cleardot.gif">Allaman</div>
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