s2dverification (version 2.5.0)

Filter: Filter Frequency Peaks From An Array

Description

This function filters from the xdata array, the signal of frequency freq. The filtering is performed by dichotomy, seeking for the frequency around freq and the phase that maximizes the signal to subtract to xdata. The maximization of the signal to subtract relies on a minimization of the mean square differences between xdata and a cosine of given frequency and phase.

Usage

Filter(xdata, freq)

Arguments

xdata

Array to be filtered.

freq

Frequency to filter.

Value

Examples

# Load sample data as in Load() example:
example(Load)
ensmod <- Mean1Dim(sampleData$mod, 2)
for (jstartdate in 1:3) {
  spectrum <- Spectrum(ensmod[1, jstartdate, ])
  for (jlen in 1:dim(spectrum)[1]) {
    if (spectrum[jlen, 2] > spectrum[jlen, 4]) {
      ensmod[1, jstartdate, ] <- Filter(ensmod[1, jstartdate, ], 
                                        spectrum[jlen, 1])
    }
  }
}
PlotAno(InsertDim(ensmod, 2, 1), sdates = startDates, fileout =
        'filtered_ensemble_mean.eps')