Dear NEST Users!

We are very excited about the release of NEST 2.20.0 earlier today, including 454 commits in 82 pull requests by 25 developers since NEST 2.18.0. 

NEST 2.20.0 brings a wide range of improvements, including


Please see below for a complete list of changes. NEST 2.20.0 is available for download from 

https://github.com/nest/nest-simulator/releases/tag/v2.20.0

To cite NEST 2.20.0, please refer to the Zenodo entry at

https://doi.org/10.5281/zenodo.3605514

WARNING: NEST 2.20.0 is affected by issue #1394, which may lead to incorrect results under certain circumstances when simulating very large networks across many MPI processes and threads. Simulations using only MPI parallelism, but no threads, work correctly according to our tests. The same holds for simulations using only thread-parallelism. The issue also affects NEST 2.18.0 and 2.16.0, but not 2.14.0. 

According to our analysis, in affected simulations, a very small number of connections is not created correctly. This happens under random cirucmstances, so that in one series of tests, out of ten identical simulations, five simulations produced correct results, while the remaining five simulations produced different results. For details, please follow the issue on GitHub.

We are currently working hard to identify the cause of this issue and hope to be able to provide a fix soon. 

The next big step forward in NEST development will be the merge of the nest-3 development branch into the master branch on GitHub. NEST 3 will bring major improvements to the user interface and considerable changes under the hood. Please see

https://nest-simulator.readthedocs.io/en/nest-3/guides/from_nest2_to_nest3.html
https://nest-simulator.readthedocs.io/en/nest-3/ref_material/nest2_vs_3.html

for more information on changes to come and modifications required to existing scripts.


Best regards,
Hans Ekkehard Plesser
President, The NEST Initiative


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NEST 2.20.0 is the result of 454 commits in 82 pull requests by 25 developers since NEST 2.18.0 which was released on June 7, 2019.

This release wraps up the 2.x series of NEST and contains many improvements and bug fixes. Highlights are the addition of the generalized leaky integrate-and-fire neuron models by the Allen Institute, STDP synapses with nearest-neighbor spike pairing schemes and improved documentation, available on Read The Docs. Following is a list of all merged pull requests:

Enhancements

Models

Installation

Documentation

Kernel

Infrastructure

PyNEST

Bug fixes

Models

Documentation

Kernel

Infrastructure

Maintenance

Models

Installation

Interpreter

Documentation

Kernel

Infrastructure

PyNEST


--

Prof. Dr. Hans Ekkehard Plesser
Head, Data Science Section

Faculty of Science and Technology
Norwegian University of Life Sciences
PO Box 5003, 1432 Aas, Norway

Phone +47 6723 1560
Email hans.ekkehard.plesser@nmbu.no
Home  http://arken.nmbu.no/~plesser