Masks

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8.3.3.3 Masks

Several functions (fitting, baseline subtraction, statistics, etc) may be run on a range of channels (or velocity/frequency ranges). You can create masks of this type using the create_mask function:

  # spave = an averaged spectrum
  spave.set_unit(’channel’)
  rmsmask=spave.create_mask([5000,7000])   # create a region over channels 5000-7000
  rms=spave.stats(stat=’rms’,mask=rmsmask) # get rms of line free region

  rmsmask=spave.create_mask([3000,4000],invert=True) # choose the region
                                                     # *excluding* the specified channels

The mask is stored in a simple Python variable (a list) and so may be manipulated using an Python facilities.

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