Species CoOccurance
Lanna, I don't know exactly what do you mean by co-occurrence data frame, but if you'd like to get a species-by-species matrix, in which you count the co-occurrences of the species (columns in the sites-by-species community matrix) with each other, you can use the crossprod function or the %*% operator for a presence/absence matrix: m <- matrix(rbinom(15,1,0.6),5,3) t(m) %*% m crossprod(m, m) HTH, Peter
On Fri, Mar 12, 2010 at 7:22 AM, Lanna Jin <lannajin at gmail.com> wrote:
Hello All, I've been sifting through tons of R Documentation, trying to find a command that converts a community matrix dataset into a species pair co-occurance data frame, and have failed miserably to find one. ?Does a function already exist in one of the community analysis packages? Thanks in advance for your response! -- Lanna Jin lannajin at gmail.com 510-898-8525 ? ? ? ?[[alternative HTML version deleted]]
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