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Bug 3030 - private/clusterstat: function is unnecessarily very slow when clustering scalar-valued 'pos' vector with triangulated neighbourhood

Reported 2015-12-16 14:14:00 +0100
Modified 2016-01-14 21:25:23 +0100
Product: FieldTrip
Component: core
Version: unspecified
Hardware: PC
Operating System: Windows
Importance: P5 normal
Assigned to: Jan-Mathijs Schoffelen
Depends on:
See also:

Jan-Mathijs Schoffelen - 2015-12-16 14:14:55 +0100

this is due to the function spending a lot of time evaluating if ~isfinite(channeighbstructmat) and because in findcluster there's an unnecessary call to spm_bwlabel for each vertex (where the intention is to find clusters over time and frequency for each vertex, which in the case of a scalar value per vertex is not needed). I intend to make two changes: clusterstat: evaluate ~isfinite(channeighbstuctmat) only once, creating a flag that can be conditionally evaluated. findcluster: only go into spm_bwlabel if nfreq*ntime>1

Jan-Mathijs Schoffelen - 2015-12-16 14:39:14 +0100

[jansch@mentat001 private]$ svn commit -m "enhancement - significant speed up of cluster functionality when clustering across scalar-valued channel or vertex space" clusterstat.m findcluster.m Sending clusterstat.m Sending findcluster.m Transmitting file data .. Committed revision 11030.