windowFunction

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Print the FWHM and Effective sensitivity bandwidth of each of the ALMA correlator window functions, or return the value for a specific choice. The values are taken from the tables in Richard Hills' note of April 8, 2012. See also onlineChannelAveraging.

Usage:

au.windowFunction(window='', channelAveraging=1, returnValue='FWHM', splineDegree=3, splineSmoothing=None)
  • window: one of ['', 'uniform','hanning','welch','cosine','hamming','bartlett', 'blackmann','blackmann-harris'] (specifying '' will print the whole table)
  • channelAveraging: 1, 2, 4, or 8; >= 16 will return channelAveraging, other values >1 will be spline-interoplated
  • returnValue: 'FWHM' or 'EffectiveBW'

Examples:

CASA <4>: au.windowFunction('hanning',returnValue='FWHM',channelAveraging=1)
  Out[4]: 2.0

CASA <31>: au.windowFunction('hanning',6,'EffectiveBW')
Warning: spline-interpolating computed table between 4 and 8
  Out[31]: 6.777660558559213

CASA <5>: au.windowFunction()
     Window type  ChanAvg  FWHM  EffectiveBW
         uniform     1    1.207   1.000
         uniform     2    1.639   2.000
         uniform     4    4.063   4.000
         uniform     8    8.033   8.000
         hanning     1    2.000   2.667
         hanning     2    2.312   3.200
         hanning     4    3.970   4.923
         hanning     8    7.996   8.828
           welch     1    1.590   1.875
           welch     2    1.952   2.565
           welch     4    4.007   4.499
           welch     8    8.001   8.470
          cosine     1    1.639   2.000
          cosine     2    2.000   2.667
          cosine     4    4.000   4.571
          cosine     8    8.000   8.533
         hamming     1    1.815   2.516
        bartlett     1    1.772   3.000
       blackmann     1    2.299   3.283
blackmann-harris     1    2.666   3.877

-- ToddHunter - 2014-02-23
Topic revision: r3 - 2016-03-02, ToddHunter
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