niche {ade4} | R Documentation |
performs a special multivariate analysis for ecological data.
niche(dudiX, Y, scannf = TRUE, nf = 2) print.niche (x, ...) plot.niche (x, xax = 1, yax = 2, ...)
dudiX |
a duality diagram providing from a function dudi.coa , dudi.pca , ... using an array sites-variables |
Y |
a data frame sites-species according to dudiX$tab with no columns of zero |
scannf |
a logical value indicating whether the eigenvalues bar plot should be displayed |
nf |
if scannf FALSE, an integer indicating the number of kept axes |
x |
an object of class niche |
... |
further arguments passed to or from other methods |
xax, yax |
the numbers of the x-axis and the y-axis |
Returns a list of the class niche
(sub-class of dudi
) containing :
rank |
an integer indicating the rank of the studied matrix |
nf |
an integer indicating the number of kept axes |
RV |
a numeric value indicating the RV coefficient |
eig |
a numeric vector with the all eigenvalues |
lw |
a data frame with the row weigths (crossed array) |
tab |
a data frame with the crossed array (averaging species/sites) |
li |
a data frame with the species coordinates |
l1 |
a data frame with the species normed scores |
co |
a data frame with the variable coordinates |
c1 |
a data frame with the variable normed scores |
ls |
a data frame with the site coordinates |
as |
a data frame with the axis upon niche axis |
Daniel Chessel chessel@biomserv.univ-lyon1.fr
Anne B Dufour dufour@biomserv.univ-lyon1.fr
Dolédec, S., Chessel, D. and Gimaret, C. (2000) Niche separation in community analysis: a new method. Ecology, 81, 2914–1927.
data(doubs) dudi1 <- dudi.pca(doubs$mil, scale = TRUE, scan = FALSE, nf = 3) nic1 <- niche(dudi1, doubs$poi, scann = FALSE) par(mfrow = c(2,2)) s.traject(dudi1$li, clab = 0) s.traject(nic1$ls, clab = 0) s.corcircle(nic1$as) s.arrow(nic1$c1) par(mfrow = c(5,6)) for (i in 1:27) s.distri(nic1$ls, as.data.frame(doubs$poi[,i]), csub = 2, sub = names(doubs$poi)[i]) par(mfrow = c(1,1)) s.arrow(nic1$li, clab = 0.7) par(mfrow = c(1,1)) data(trichometeo) pca1 <- dudi.pca(trichometeo$meteo, scan = FALSE) nic1 <- niche(pca1, log(trichometeo$fau + 1), scan = FALSE) plot(nic1) data(rpjdl) plot(niche(dudi.pca(rpjdl$mil, scan = FALSE), rpjdl$fau, scan = FALSE))