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en:hier-divisive_examples

Section: Numerical classification

TWINSPAN (hierarchical divisive classification)

Example

Run TWINSPAN example1), which shows modified TWINSPAN on traditional Ellenberg's Danube meadow dataset, projected on DCA ordination diagram and compared with original classification into three vegetation types (plus one not-classified releve) made by tabular sorting:

library (twinspanR)
library (vegan)
data (danube)
res <- twinspan (danube$spe, modif = TRUE, clusters = 4)
k <- cut (res)
dca <- decorana (danube$spe)
par (mfrow = c(1,2))
ordiplot (dca, type = 'n', display = 'si', main = 'Modified TWINSPAN')
points (dca, col = k)
for (i in c(1,2,4)) ordihull (dca, groups = k, show.group = i, col = i,
 draw = 'polygon', label = TRUE)
ordiplot (dca, type = 'n', display = 'si', main = 'Original assignment\n (Ellenberg 1954)')
points (dca, col = danube$env$veg.type)
for (i in c(1:3)) ordihull (dca, groups = danube$env$veg.type,
 show.group = unique (danube$env$veg.type)[i], col = i,
 draw = 'polygon', label = TRUE)

1)
You would get the same result as the script below if you run example (twinspan) - this will run the example which comes with the help file of twinspan function (see the section Examples in ?twinspan).
en/hier-divisive_examples.txt · Last modified: 2019/03/22 23:01 by David Zelený