[R] Randomising matrices
s0455078 at sms.ed.ac.uk
Fri Apr 27 10:45:38 CEST 2007
I would like to be able to randomise presence-absence (i.e. binary)
matrices whilst keeping both the row and column totals constant. Is
there a function in R that would allow me to do this?
I'm working with vegetation presence-absence matrices based on field
observations. The matrices are formatted to have sites as rows and
species as columns. The presence of a species on a site is indicated
with a 1 (absence is obviously indicated with a 0).
I would like to randomise the matrices many times in order to construct
null models. However, I cannot identify a function in R to do this, and
the programming looks tricky for someone of my limited skills.
Can anybody help me out?
Institute of Geography
School of Geosciences
University of Edinburgh
Edinburgh EH8 9XP
Tel: 0131 650 2532
More information about the R-help