filter

Applies a Butterworth filter to the seismograms. The filterType can be CAUSAL or NONCAUSAL or TWOPASS, with the last two being equivalent.

Example 

<filter>
  <lowFreqCorner>
      <value>50</value>
      <unit>SECOND</unit>
  </lowFreqCorner>
  <highFreqCorner>
      <value>5</value>
      <unit>HERTZ</unit>
  </highFreqCorner>
  <numPoles>2</numPoles>
  <filterType>NONCAUSAL</filterType>
</filter>

This consists of

<filter>

<lowFreqCorner> </lowFreqCorner>
<highFreqCorner> </highFreqCorner>
<numPoles>integer</numPoles>
<filterType>
choice
NONCAUSAL
CAUSAL
TWOPASS
end choice
</filterType>
</filter>

Places this can be found

In seismogramProcess there is a choice between all of the following