Connectionists: Announcing: Emergent Neural Network Simulation Software (formerly PDP++)

[Randall C. O'Reilly]

Announcing: The Emergent Neural Network Simulation System
http://grey.colorado.edu/emergent/index.php/Main_Page

Emergent is a major rewrite of the widely used PDP++ system.

Emergent is a comprehensive simulation environment for creating complex, 
sophisticated models of the brain and cognitive processes using neural 
network models.  These networks can also be used for all kinds of other more 
pragmatic tasks, like predicting the stock market or analyzing data.  
Emergent includes a full GUI environment for constructing networks and the 
input/output patterns for the networks to process, and many different 
analysis tools for understanding what the networks are doing.  It has a new 
tabbed-browser style interface (in Qt 4), with full 3D graphics (via Open 
Inventor/Coin3D), and powerful new GUI programming tools and data processing 
and analysis capabilities.  It supports the same algorithms as PDP++: 
Backpropagation (feedforward and recurrent), Self-Organizing (e.g., Hebbian, 
Kohonen, Competitive Learning), Constraint Satisfaction (e.g., Boltzmann, 
Hopfield), and the Leabra algorithm that integrates elements of all of the 
above in one coherent, biologically-plausible framework.

Relative to PDP++, the main advances are:

* Much easier to modify and extend the "scripting" of network training through 
a new GUI-based programming system -- everything is transparent and 
user-modifiable.  Considerable support is included for implementing complex 
psychological tasks via this programming environment.

* The tabbed browser allows everything to be contained within a single window, 
with full search functions, cut/copy/paste, drag-and-drop, etc, for a modern, 
highly efficient working environment.

* Everything has been boiled down to the most basic, general-purpose elements, 
which can now be combined in more powerful, "emergent" ways.  Environments 
and monitor data and all other forms of data have been consolidated in a 
single powerful DataTable object that supports many different kinds of 
operations (e.g., database-style Joins and Sorts, vector and matrix math, 3d 
graphing, statistics, etc).  With convenient interfaces for DataTables in the 
GUI programming environment, flexible and efficient data processing and 
analysis functions can be readily performed.

* Has a greater variety of network visualization tools, and a built-in virtual 
environment simulator (based on the popular ODE toolkit) allows networks to 
interact with a realistic simulated environment, to explore more embodied and 
robotic functionality.

* Standard GPL license, ./configure build process, native look-and-feel on all 
3 major platforms (Linux, Mac, Windows), easily-installable binary packages 
(including apt & yum on linux), and dynamically-loadable plugin modules.

Relative to the prevalent use of MATLAB and other general-purpose tools for 
neural neural network simulation, Emergent offers several important 
advantages:

* completely open source, free software.

* highly optimized execution speed, including distributed memory computation, 
while also supporting complex biologically-based neural architectures.

* designed specifically to make research simulations easily accessible to 
other users with minimal additional effort: built-in documentation system, 
pervasive comment fields, accessible, transparent interface.

In brief, if you're doing large scale, complex neural network models, Emergent 
offers many advantages.