Find turning points (peaks or pits) Determine the number and the position of extrema (turning points, either peaks or pits) in a regular time series.

Find turning points (peaks or pits) Determine the number and the position of extrema (turning points, either peaks or pits) in a regular time series.

turnpoints(x)

Arguments

x	vector or a time series

Value

An object of type 'abrTurnpoints' is returned, with:

data

The dataset to which the calculation is done

n

The number of observations

points

The value of the points in the series, after elimination of ex-aequos

pos

The position of the points on the time scale in the series (including ex-aequos)

exaequos

Location of exaequos (1), or not (0)

nturns

Total number of tunring points in the whole time series

firstispeak

Is the first turning point a peak (TRUE), or not (FALSE)

peaks

Logical vector. Location of the peaks in the time series without ex-aequos

pits

Logical vector. Location of the pits in the time series without ex-aequos

tppos

Position of the turning points in the initial series (with ex-aequos)

References

Ibanez, F. (1982) Sur une nouvelle application de la theorie de l'information a la description des series chronologiques planctoniques. J. Exp. Mar. Biol. Ecol., 4:619-632

Grosjean, P. and Ibanez, F. (2014) pastecs: Package for Analysis of Space-Time Ecological Series. R package version 1.3-18. https://CRAN.R-project.org/package=pastecs

Author

This is a stripped-down version taken from package pastecs, original authors are Frédéric Ibanez, Philippe Grosjean. The original code and the derived version are licensed under the GPL (>=2).