phi {untb} | R Documentation |
Hubbell's phi
Description
Hubbell's phi: counts of species abundances
Usage
phi(x,addnames=TRUE)
unphi(freq, string="spp")
Arguments
x |
Ecosystem vector; is coerced to class |
addnames |
Boolean with default
|
freq |
Frequency data (eg as returned by |
string |
Character; species name to prepend (using |
Details
Function phi()
coerces its argument to a count
object and
by default returns a named vector whose th element is the
number of species with
individuals. The name of the
th element is the species with abundance
if unique
and empty otherwise. Function
phi()
is used by
theta.prob()
.
Function unphi()
does the reverse: given the output of
phi()
, it returns a corresponding count
object. Note that
species names are lost.
Note
The code for setting the names is a dog's breakfast
Author(s)
Robin K. S. Hankin
References
S. P. Hubbell 2001. “The Unified Neutral Theory of Biodiversity”. Princeton University Press.
See Also
Examples
jj <- c(rep("oak",5) ,rep("ash",2),rep("elm",3),"pine","tea","yew")
a <- as.count(jj)
phi(a)
unphi(phi(a)) #should match 'a' except for species names (which are lost)
data(butterflies)
phi(butterflies,add=FALSE)
summary(unphi(phi(butterflies))) #should match 'summary(butterflies)'