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dplR (version 1.6.4)

detrend: Detrend Multiple Ring-Width Series Simultaneously

Description

This is a wrapper for detrend.series to detrend many ring-width series at once.

Usage

detrend(rwl, y.name = names(rwl), make.plot = FALSE, method = c("Spline", "ModNegExp", "Mean", "Ar", "Friedman"), nyrs = NULL, f = 0.5, pos.slope = FALSE, constrain.modnegexp = c("never", "when.fail", "always"), verbose = FALSE, return.info = FALSE, wt, span = "cv", bass = 0)

Arguments

rwl
a data.frame with series as columns and years as rows such as that produced by read.rwl
y.name
a character vector of length(ncol(rwl)) that gives the ID of each series. Defaults to the column names of rwl.
make.plot
a logical flag. Makes plots of the raw data and detrended data if TRUE. See details below.
method
a character vector to determine the detrending methods. See details below. Possible values are all subsets of c("Spline", "ModNegExp", "Mean", "Ar"). Defaults to using all the available methods.
nyrs
a number giving the rigidity of the smoothing spline, defaults to 0.67 of series length if nyrs is NULL.
f
a number between 0 and 1 giving the frequency response or wavelength cutoff. Defaults to 0.5.
pos.slope
a logical flag. Will allow for a positive slope to be used in method "ModNegExp". If FALSE the line will be horizontal.
constrain.modnegexp
a character string which controls the constraints of the "ModNegExp" model. See detrend.series for further details.
verbose
logical. Write out details?
return.info
a logical flag. If TRUE, details about models and data will be added to the return value. See ‘Value’.
wt
a numeric vector of case weights for method "Friedman". The default means equals weights.
span
a numeric value controlling method "Friedman", or "cv" (default) for automatic choice by cross-validation. See supsmu.
bass
a numeric value controlling the smoothness of the fitted curve in method "Friedman". See supsmu.

Value

If one detrending method is used, a data.frame containing the dimensionless detrended ring widths with column names, row names and dimensions of rwl. If more methods are used, a list with ncol(rwl) elements each containing a data.frame with the detrended ring widths in each column.If return.info is TRUE, the return value is a list with three parts:
series
the main result described above (data.frame or list of data.frames)
model.info
Information about the models corresponding to each output series. A list with one element for each column of rwl. See detrend.series (‘Value’, model.info) for a description of the contents.
data.info
Information about the input series. A list with one element for each column of rwl. See detrend.series (‘Value’, data.info).

Details

See detrend.series for details on detrending methods. Setting make.plot = TRUE will cause plots of each series to be produced. These could be saved using Devices if desired.

See Also

detrend.series

Examples

Run this code
data(ca533)
## Detrend using modified exponential decay. Returns a data.frame
ca533.rwi <- detrend(rwl = ca533, method = "ModNegExp")

## Not run: 
# library(grDevices)
# ## Detrend using all methods. Returns a list
# ca533.rwi <- detrend(rwl = ca533)
# ## Save a pdf of all series
# fname <- tempfile(fileext=".pdf")
# print(fname) # tempfile used for output
# pdf(fname)
# ca533.rwi <- detrend(rwl = ca533, method = c("Spline", "ModNegExp"),
#                      make.plot = TRUE)
# dev.off()
# 
# unlink(fname) # remove the file
# ## End(Not run)

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