PyNN 0.8.2 release notes

6th December 2016

Welcome to PyNN 0.8.2!

New spike sources

Two new spike source models were added, with implementations for the NEST and NEURON backends: SpikeSourceGamma (spikes follow a gamma process) and SpikeSourcePoissonRefractory (inter-spike intervals are drawn from an exponential distribution as for a Poisson process, but there is a fixed refractory period after each spike during which no spike can occur).

Other changes

  • Changed the save_positions() format from id x y z to index x y z to make it simulator independent.

  • Added histograms to the utility.plotting module.

  • Added a multiple_synapses flag to Projection.get(..., format="array")() to control how synaptic parameters are combined when there are multiple connections between pairs of neurons. Until now, parameters were summed, which made sense for weights but not for delays. We have adopted the Brian approach of adding an argument multiple_synapses which is one of {'last', 'first', 'sum', 'min', 'max'}. The default is sum.

  • Assorted bug fixes