Dear Friends, Using package Vegan, I need to calculate Shannons Diversity index and Pielou's Evenness for a set of 20 study areas. Each area is represented by a matrix of 25 sample plots x tree species. The code is as following, where data stands for the data matrix of any of the 20 areas:
S <- specnumber(data) H <- diversity(data) J <- H/log(S) I indexed the 20 areas by a column with the number of each of the areas and have been trying to formulate a code to iterate this procedure for each of the 20 areas and save the results in a table, but I have not been successful. Do anyone have a hint on how to do that? Thaks very much in advance, Sincerely, Alexandre Dr. Alexandre F. Souza Programa de Pós-Graduação em Biologia: Diversidade e Manejo da Vida Silvestre Universidade do Vale do Rio dos Sinos (UNISINOS) Av. UNISINOS 950 - C.P. 275, São Leopoldo 93022-000, RS - Brasil Telefone: (051)3590-8477 ramal 1263 Skype: alexfadigas afso...@unisinos.br http://www.unisinos.br/laboratorios/lecopop -- Esta mensagem foi verificada pelo sistema de antiv�rus e acredita-se estar livre de perigo.
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