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mariomulansky / PySpike

Python implementation of spike distance metrics
http://mariomulansky.github.io/PySpike
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Doublets in x values of isi_profile and spk_profile #74

Closed CyprianAdler closed 5 months ago

CyprianAdler commented 6 months ago

Why are there doublets in the x values of the isi and spk profile?

Here is a screenshot of the x values that were obtained by using isi_profile.get_plottable_data() grafik

The same problems also happens for the spk_profile. Interestingly the y values of the spk_profile are different for the same x values: grafik

thomaskreuz commented 5 months ago

Hi CyprianAdler,

sorry for answering only now.

The doublets are correct. They occur at the positions of the spikes when the interspike intervals and the distances to nearest neighbors change. You get one value for the previous interval and one value for the following interval. And so typically you have instantaneous jumps in the profiles at these positions. Between these jumps the profile of the ISI-distance is piecewise constant so that's why you have the same y-values repeating twice, whereas the SPIKE-distance is piecewise linear so the y-values change (as you correctly noticed). You will find an illustration of this in Fig. 3 of this article (and a description in the text at the bottom of page 3437):

https://drive.google.com/file/d/16rdVbJFj7BypaaI10aHpXLk0WJuJ7reM/view

I hope this explains everything. Just let me know if you have further questions.