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Spectrum
User definable spectrum analysis 1
User definable spectrum analysis 2
Find peaks in a power spectrum
Coherence of two waveforms
Waterfall display of FFT power

System for User Definable Spectrum Analysis I
PC: sudsa1.zip 19,016 Mac: sudsa1.sit 21,094

This is the first of two scripts for looking at the power of frequencies in user definable frequency bands.

The user is asked to specify an analysis region, this region is then split up into a number of epochs. Each epoch is analysed in turn and the power of frequencies within each band in each epoch for each channel are dumped to a data file.


System for User Definable Spectrum Analysis II
PC: sudsa22.zip 9,615 Mac: sudsa2.sit 34,817

This second script for doing spectral analysis in user definable frequency bands has a slightly different approach than SUDSA1. This script is more applicable to users who have lots of short epochs. There are several different analyses which can be performed and in each case the results may be dumped to a text file. The analysis modes available are:

  1. Dominant frequency.
  2. Power of dominant frequency.
  3. Total power of frequencies in bands.
  4. Log power of dominant frequency.
  5. Log total power of frequencies in bands.
  6. Root mean square amplitude.
  7. Cross correlation.
Options 4 and 5 are not available on the Mac version.


Find peaks in a power spectrum
PC: PSpeaks.zip 134,296

This script identifies peaks in a power spectrum stored in a Spike2 result view.

The highest peak and up to 9 other peaks are marked with cursors and a table of up to 50 peak frequency and power values is written to the log view.

This script requires Spike 2 version 4 or higher.


Coherence of two waveforms
PC : coher.zip 24,827 Mac : coher.sit 27,492

The coherence of two waveforms is the measure of their similarity in frequency content. Coherence is a function of frequency and ranges from 0 for totally incoherent waveforms to 1.0. This script generates the coherence and provides a menu in which the two channels to be used and the number of frequencies in the result are set. Up to 2048 frequencies may be calculated.

The principles and operation of the script are fully described in a Word document file that is enclosed with the script.


Waterfall display of FFT power
PC: spike\scripts\FFTwater.s2s

This script generates a waterfall display using the results of power spectrum analysis, the resulting display is valuable for showing changes in spectral content over time. Requires version 3 or later.


Some of these scripts have come from users rather than the CED team. If you have a script that you would like to offer to fellow users via this page, please tell Simon Gray. We provide some scripts for Signal too.

These scripts are stored as WinZip files, myscript.zip, except where they are shown as spike\scripts\myscript.s2s. Those latter files were installed with Spike2 and spike stands for the directory in which you installed Spike2. See the summaries by clicking on the description line, below. Then you can down-load them by clicking on the filename; please check the size received.
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