Method ao/lpsd


  LPSD implements the LPSD algorithm for analysis objects.
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  DESCRIPTION: LPSD implements the LPSD algorithm for analysis objects.
 
  CALL:        bs = lpsd(a1,a2,a3,...,pl)
               bs = lpsd(as,pl)
               bs = as.lpsd(pl)
 
  INPUTS:      aN   - input analysis objects
               as   - input analysis objects array
               pl   - input parameter list
 
  OUTPUTS:     bs   - array of analysis objects, one for each input
 
  Parameters Description
 
  References:  "Improved spectrum estimation from digitized time series
                on a logarithmic frequency axis", Michael Troebs, Gerhard Heinzel,
                Measurement 39 (2006) 120-129.
 
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Method Details
Access public
Defining Class ao
Sealed 0
Static 0

Parameter Description

Default

no description
Key Default Value Options Description
lpsd
WIN 'Hanning'
  • '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. [default: taken from user prefs]
Only the design parameters of the window object are used. Enter a string value containing the window name e.g.
plist('Win', 'Kaiser', 'psll', 200)
plist('Win', 'BH92')
PSLL 200 none The peak sidelobe level for Kaiser windows.
Note: it is ignored for all other windows
OLAP -1 none The segment percent overlap [-1 == take from window function]
ORDER, N 0
  • -1
  • 0
  • 1
  • 2
  • 3
  • 4
  • 5
  • 6
  • 7
  • 8
  • 9
The order of segment detrending:
  • -1 - no detrending
  • 0 - subtract mean
  • 1 - subtract linear fit
  • N - subtract fit of polynomial, order N
DROP WINDOW SAMPLES 1
  • 1
  • 0
Drop the recommended (by the window) number of samples of the final computed spectral series.
TIMES, SPLIT [] none The time range to analyze. If not empty, sets the time interval to operate on.
As in ao/split, the interval can be specified by:
  • a vector of doubles
  • a timespan object
  • a cell array of time strings
  • a vector of time objects
MASK [] none Mask out segments in the averaging process. The mask should be a vector of logical values, one value per segment being averaged. The plist method [psdSegments] can be used to generate a default mask for your PSD settings. If empty, all segments will be included in the average.
KDES 100 none The desired number of averages.
JDES 1000 none The desired number of spectral frequencies to compute.
LMIN 0 none The minimum segment length.
SCALE 'PSD'
  • 'PSD'
  • 'ASD'
  • 'PS'
  • 'AS'
The scaling of output. Choose from:
  • PSD - Power Spectral Density
  • ASD - Amplitude (linear) Spectral Density
  • PS - Power Spectrum
  • AS - Amplitude (linear) Spectrum

Example

plist('WIN', 'Hanning', 'PSLL', [200], 'OLAP', [-1], 'ORDER', [0], 'DROP WINDOW SAMPLES', [true], 'TIMES', [[]], 'MASK', [[]], 'KDES', [100], 'JDES', [1000], 'LMIN', [0], 'SCALE', 'PSD')

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Some information of the method ao/lpsd are listed below:
Class name ao
Method name lpsd
Category Signal Processing
Package name ltpda
Can be used as modifier 1
Supported numeric types {'double'}




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