scipy.signal.vectorstrength(events, period)[source]

Determine the vector strength of the events corresponding to the given period.

The vector strength is a measure of phase synchrony, how well the timing of the events is synchronized to a single period of a periodic signal.

If multiple periods are used, calculate the vector strength of each. This is called the “resonating vector strength”.


events : 1D array_like

An array of time points containing the timing of the events.

period : float or array_like

The period of the signal that the events should synchronize to. The period is in the same units as events. It can also be an array of periods, in which case the outputs are arrays of the same length.


strength : float or 1D array

The strength of the synchronization. 1.0 is perfect synchronization and 0.0 is no synchronization. If period is an array, this is also an array with each element containing the vector strength at the corresponding period.

phase : float or array

The phase that the events are most strongly synchronized to in radians. If period is an array, this is also an array with each element containing the phase for the corresponding period.


van Hemmen, JL, Longtin, A, and Vollmayr, AN. Testing resonating vector
strength: Auditory system, electric fish, and noise. Chaos 21, 047508 (2011); doi: 10.1063/1.3670512
van Hemmen, JL. Vector strength after Goldberg, Brown, and von Mises:
biological and mathematical perspectives. Biol Cybern. 2013 Aug;107(4):385-96. doi: 10.1007/s00422-013-0561-7.
van Hemmen, JL and Vollmayr, AN. Resonating vector strength: what happens
when we vary the “probing” frequency while keeping the spike times fixed. Biol Cybern. 2013 Aug;107(4):491-94. doi: 10.1007/s00422-013-0560-8