Dear List,
I want to compare the presence and absence of bird species based on the sites in a matrix. The matrix has 5 rows for Island A, B, C, D, and E. It has 100 columns for bird species D001-D100. In each cell of the matrix, the presence-absence of bird species will be recorded as 1 or 0. (For example, if species D001 is found on Island D, the matrix cell of species D001 and Island D will be 1.) Now I want to know the different bird species between Island B and E. In other words, I would like to find out bird species present (1) on Island B but absent (0)on island E, and vice versa (absent (0) on Island B but present (1)on island E). Please kindly advise how to code the purpose above. Thank you in advance. Elaine [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.