psdDF2NoiseMatrix {IRISSeismic}

Apply instrument correction to PSDs

Description

The psdDF2NoiseMatrix function uses the snclq identifier associated with the first PSD in the dataframe to obtain instrument correction information at the specified frequencies from the getEvalresp web service if instrumentation correction information is not supplied as an argument. This correction is applied to every PSD in the dataframe and the now corrected PSD values are returned as a matrix.

Usage

psdDF2NoiseMatrix(DF, evalresp=NULL)

Arguments

DF

a dataframe of PSDs obtained from the getPSDMeasurements method of IrisClient.

evalresp

dataframe of freq, amp, phase information matching output of getEvalresp, optional.

Details

This function is identical in behavior to psdList2NoiseMatrix except that the input object is a dataframe of PSD values obtained from the MUSTANG Backend Storage System.

Value

A matrix is returned with one row for each instrument-corrected PSD and one column for each frequency bin.

Note

The incoming dataframe is checked to make sure that it represents only a single SNCL (Station-Network-Channel-Location). An error is generated if more than one is found. However, the psdDF is not checked to make sure that no changes to the instrument correction happened during the time period covered by the psdDF. This occurs at an 'epoch' boundary when an instrument is replaced.

Author(s)

Jonathan Callahan [e-mail]

References

Seismic Noise Analysis System Using Power Spectral Density Probability Density Functions (McNamara and Boaz 2005)

See Also

McNamaraPSD, psdList, psdList2NoiseMatrix, psdPlot, psdStatistics