labdsv (version 1.8-0)

rndtaxa: Randomize a Taxa Data.Frame

Description

Permutes a vegetation (or other) data.frame to establish a basis for null model tests in vegetation ecology.

Usage

rndtaxa(taxa,replace=FALSE,species=FALSE,plots=FALSE)

Arguments

taxa

the vegetation (or other taxon) data.frame, samples as rows, species as columns

replace

a switch for permuting (if FALSE) or boostrapping (if TRUE)

species

a switch to control randomizing by species (if TRUE), maintaining species occurrence distributions

plots

a switch to control randomizing by samples (if TRUE), maintaining plot-level species richness

Value

a data.frame with samples as rows and species as columns of the same dimensions as entered.

Details

Permutes or bootstraps a vegetation data frame for input to dist, vegdist, dsvdis, or other routines. Can randomize by columns (species=TRUE), samples (plots=TRUE), or fully (neither species nor plots = TRUE).

Examples

# NOT RUN {
    data(bryceveg) # returns a vegetation data.frame called bryceveg
    test <- rndtaxa(bryceveg,species=TRUE) # preserves species abundance
            # distribution
    test2 <- rndtaxa(bryceveg,plots=TRUE) # preserves plot-level 
                                          # species richness
# }