LTPDA Toolbox™ contents Method: ao/polynomfit   Method: ao/ppsd

Method ao/powerFit

  POWERFIT fits a piecewise powerlaw to the given data.
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  DESCRIPTION: POWERFIT fits a piecewise powerlaw to the given data by
               minimising the log-likelihood function.
 
 
  CALL:        out = obj.powerFit(pl)
               out = powerFit(objs, pl)
 
  INPUTS:      pl      - a parameter list
               obj(s)  - input ao object(s)
 
  OUTPUTS:     out - some output.
 
 
  Created 2013-02-20, M Hewitson
      - adapted from code writen by Curt Cutler and Ira Thorpe.
 
  Parameters Description
 
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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
powerFit
ORDERS 0 none The powers of the dependent variable to fit to the data.
P0 1 none An initial guess for the power-law coefficients.
OFFSETS [] none offset frequencies of the power-law from DC.
UB [] none Array of upper bounds for parameters. If empty, the upper bound is +Inf for all variables.
LB [] none Array of lower bounds for parameters. If empty, the lower bound is -Inf for all variables.
WEIGHTS [] none Weights for individual data bins. If empty, all bins are weighted equally. Can also be a plist for a built-in ao model
FUNCTION 'Sum'
  • 'Sum'
  • 'Median'
  • 'Exponential'
 Function to use when calculating the liklihood.
  • Sum - Sum the likelihood over all bins
  • Median - Take the median likelihood over all bins
  • Exponential - Apply an exponential weighting to the likelihood to reduce influence of noise spikes
EXP_FACT 7 none Factor used in exponential weighting of likelihood funciton

Example
plist('ORDERS', [0], 'P0', [1], 'OFFSETS', [[]], 'UB', [[]], 'LB', [[]], 'WEIGHTS', [[]], 'FUNCTION', 'Sum', 'EXP_FACT', [7])

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Some information of the method ao/powerFit are listed below:
Class name ao
Method name powerFit
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/polynomfit  Method: ao/polynomfit   Method: ao/ppsd Method: ao/ppsd

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