astrochron (version 0.4.3)

bandpass: Bandpass Filter Stratigraphic Series

Description

Bandpass filter stratigraphic series using rectangular, Gaussian or tapered cosine window

Usage

bandpass(dat,padfac=2,flow=NULL,fhigh=NULL,win=0,alpha=3,p=0.25,demean=T,
         detrend=F,addmean=T,output=1,xmin=0,xmax=Nyq,genplot=T,verbose=T)

Arguments

dat

Stratigraphic series for bandpass filtering. First column should be location (e.g., depth), second column should be data value.

padfac

Pad with zeros to (padfac*npts) points, where npts is the original number of data points.

flow

Lowest frequency to bandpass.

fhigh

Highest frequency to bandpass.

win

Window type for bandpass filter: 0 = rectangular , 1= Gaussian, 2= Cosine-tapered window.

alpha

Gaussian window parameter: alpha is 1/stdev, a measure of the width of the Dirichlet kernel. Choose alpha >= 2.5.

p

Cosine-tapered window parameter: p is the percent of the data series tapered (choose 0-1).

demean

Remove mean from data series? (T or F)

detrend

Remove linear trend from data series? (T or F)

addmean

Add mean value to bandpass result? (T or F)

output

Output: (1) filtered series, (2) bandpass filter window.

xmin

Smallest frequency for plotting.

xmax

Largest frequency for plotting.

genplot

Generate summary plots? (T or F)

verbose

Verbose output? (T or F)

Value

• bandpassed stratigraphic series.

See Also

lowpass, noKernel, noLow, prewhiteAR, prewhiteAR1, and taner

Examples

# generate example series with 3 precession terms and noise
ex <- cycles(noisevar=.0004,dt=5)
# bandpass precession terms using cosine-tapered window 
res_ex <- bandpass(ex,flow=0.038,fhigh=0.057,win=2,p=.4)