LTPDA Toolbox™ contents Method: ao/fftfilt   Method: ao/filter

Method ao/filtSubtract

  FILTSUBTRACT subtracts a frequency dependent noise contribution from an input ao.
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  DESCRIPTION: FILTSUBTRACT subtracts a frequency dependent noise contribution from an input ao.
               The method computes the transfer function between both input AOs and
               fits a miir model to it. The frequency band is applied is set by a
               threshold in the coherence that the user defines as an input
               parameter.
 
  CALL:        c = filtSubtract(a,b pl)
 
  INPUTS:      a  - AO from where subtract linear contributions
               b  - AOs with noise contributions
               pl - parameter list (see below)
 
  OUTPUTs:     c  - output AO with contributions subtracted (tsdata)
 
  Parameters Description
 
  TODO: handling errors
        split by coherence function
 
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Method Details
Access public
Defining Class ao
Sealed 0
Static 0

Parameter Description

Sets for this method …
Default

Default
no description
Key Default Value Options Description
filtSubtract
FS [] none target sampling frequency to resample the data.
TIMES '' none selects the interval where the subtraction is applied.
TIMES POSTFILTER '' none selects the filter transient intervals to be removed.
FREQUENCIES '' none selects the frequency band where the transfer
FILT '' none a miir/mfir object which will be used as a
transfer function. If this option is selected
the fit is avoided.
AUTOSEARCH 'on'
  • 'on'
  • 'off'
 (ao.zDomainFit)
MAXITER 50 none Maximum number of iterations in fit routine (ao.zDomainFit).
MINORDER 2 none Minimum order to fit with (ao.zDomainFit).
MAXORDER 20 none Maximum order to fit with (ao.zDomainFit).
WEIGHTPARAM 'abs'
  • 'ones'
  • 'abs'
  • 'sqrt'
 (ao.zDomainFit)
FORCESTABILITY 'off'
  • 'on'
  • 'off'
 Force poles to be stable (ao.zDomainFit)
PLOT 'off'
  • 'on'
  • 'off'
 Plot results of each fitting step (ao.zDomainFit)
CHECKPROGRESS 'off'
  • 'on'
  • 'off'
 Display the status of the fit iteration. (ao.zDomainFit)
KDES 100 none The desired number of averages (ao.ltfe).
JDES 1000 none The desired number of spectral frequencies to compute (ao.ltfe).
SCALE '' none
TYPE '' none
WIN 'BH92'
  • 'Rectangular'
  • 'Welch'
  • 'Bartlett'
  • 'Hanning'
  • 'Hamming'
  • 'Nuttall3'
  • 'Nuttall4'
  • 'Nuttall3a'
  • 'Nuttall3b'
  • 'Nuttall4a'
  • 'Nuttall4b'
  • 'Nuttall4c'
  • 'BH92'
  • 'SFT3F'
  • 'SFT3M'
  • 'FTNI'
  • 'SFT4F'
  • 'SFT5F'
  • 'SFT4M'
  • 'FTHP'
  • 'HFT70'
  • 'FTSRS'
  • 'SFT5M'
  • 'HFT90D'
  • 'HFT95'
  • 'HFT116D'
  • 'HFT144D'
  • 'HFT169D'
  • 'HFT196D'
  • 'HFT223D'
  • 'HFT248D'
  • 'Kaiser'
  • 'levelledHanning'
 The window to be applied to the data to remove the discontinuities at edges of segments (ao.ltfe).

Example
plist('FS', [[]], 'TIMES', '', 'TIMES POSTFILTER', '', 'FREQUENCIES', '', 'FILT', '', 'AUTOSEARCH', 'on', 'MAXITER', [50], 'MINORDER', [2], 'MAXORDER', [20], 'WEIGHTPARAM', 'abs', 'FORCESTABILITY', 'off', 'PLOT', 'off', 'CHECKPROGRESS', 'off', 'KDES', [100], 'JDES', [1000], 'SCALE', '', 'TYPE', '', 'WIN', 'BH92')

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Some information of the method ao/filtSubtract are listed below:
Class name ao
Method name filtSubtract
Category Signal Processing
Package name ltpda
VCS Version 967b0eec0dece803a81af8ef54ad2f8c784b20b2
Min input args 1
Max input args -1
Min output args 1
Max output args -1
Can be used as modifier 1
Supported numeric types {'double'}



Method: ao/fftfilt  Method: ao/fftfilt   Method: ao/filter Method: ao/filter

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