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en:ca_dca_r
Section: Ordination analysis
CA & DCA (unimodal unconstrained ordination)
R functions
cca(libraryvegan) - if the environmental matrix is not specified,ccafunction inveganpackage calculates unconstrained correspondence analysis1).decorana(libraryvegan) - this function implements the original DECORANA program, written by Mark Hill in Fortran, into R. For historical reasons2), only four DCA ordination axes are returned, and this is not easy to change.CA(P. Legendre, Numerical Ecology with R, calledCA.newrin the 2nd edition) - code can be found here.
1)
Alternatively to library
vegan, there is also a package ca with function ca calculating correspondence analysis, with plot, plot3d and summary functions. Package ade4 offers function dudi.coa.2)
The function
decorana is implementing the original Hill's algorithm for DCA introduced by Fortran program DECORANA, which itself can calculate only four ordination axes; CANOCO behaves in the same way.en/ca_dca_r.txt · Last modified: 2021/03/03 19:52 by David Zelený
