dave (version 2.0)

vvelocity: Printing ordinations of velocity and acceleration and differently transformed speed profiles

Description

Given a data frame of a multivariate (vegetation) time series this plots a pco ordination using circles with diameters proportional to rate of change (velocity), a pco ordination pco using cirlces with diameters proportional to change in velocity (acceleration) and three velocity profiles with differently transformed species scores (from quantitative to qualitative).

Usage

vvelocity(pveg, timescale, y, ...)
vvelocity2(pveg, timescale, y=1)
# S3 method for default
vvelocity(pveg,timescale,y,...)
# S3 method for vvelocity
plot(x,tlabs,scal=1,...)

Arguments

pveg

A data frame of a multivariate (vegetation) time series

timescale

A vector of points in time of releves (rows)

y

Transformation of species scores: x'= x exp(y)

…

Additional arguments passed to plot.

tlabs

A vector of releve labels used for annotation of data points in ordinations. See example.

scal

A variable for scaling the circles in the ordinations. Default is scal=1.

x

An object of class "vvelocity".

Value

An object of class "vvelocity" with at least the following items:

pveg

The input vegetation data frame

timescale

The input time scale

y

Transformation of species scores: x'= x exp(y)

Details

See also pco for the ordinations used.

References

Wildi, O. 2017. Data Analysis in Vegetation Ecology. 3rd ed. CABI, Oxfordshire, Boston.

Examples

# NOT RUN {
tlabs<- c(1,15,48,60,100,122,145)
timescale<- psit$Years.B.P
o.vvel<- vvelocity(pveg,timescale,y=0.5)
plot(o.vvel,tlabs=tlabs,scal=1)
# }