[R] RV: By sentence

[Jorge Cornejo Donoso]

Hi dear listers

	Do you know how to made a mean by one or more categorical variables?
	I can do that quite easy on SAS by in R I just can't do it E.g.
	Some fishes
	Sex 	Lenght
	male	15
	fema	20
	fema	17
	fema	19
	male  18

	So the idea is mean(Lenght) by sex, in order to have sex: Male
mean=XX Sex: Fema mean=YY
	In this case is quite easy to do it by a loop, but I have a huge DB
so is not an option. Any suggestion?

	Thanks in advance!

--

Jorge Cornejo Donoso

Universidad Austral de Chile

Portales 73, Coyhaique,CP 5950000, Region de Aisén, Chile Tel +56 67 244520
Fax +56 67 239377