bukys (04/08/89)
From: bukys =============================================================================== ANSWERS TO COMMON QUESTIONS REGARDING THE ROCHESTER CONNECTIONIST SIMULATOR Fri Apr 7 12:34:10 EDT 1989 Liudvikas Bukys <bukys@cs.rochester.edu> =============================================================================== WHAT IS THE SIMULATOR? The Rochester Connectionist Simulator is a tool that allows you to build and experiment with connectionist networks. It provides the basic mechanism for running a simulation (iterate through all units, call functions, update values). It also provides a graphic interface that lets you examine the state of a network. It also provides convenient facilities for defining and manipulating your network: names for units, set manipulation, etc. It also has a dynamic loading facility, so you can compile and load new functions on the fly, and to allow to customize the simulator by adding your own commands. There is also a library to help you implement back-propagation networks. The Simulator does come with a few simple canned examples, but does not provide a lot of the latest greatest gizmos that researchers have dreamed up. You should think of the simulator as a network programmer's tool -- you have the tool, but you have to know what to do with it. WHAT MACHINES DOES IT RUN ON? We have run it here on VAX and SUN-3 (SunOS 3.x) systems here. It has been made to run on SUN-4 systems without too much trouble. It's a little boring without the graphic interface, though, and... The graphic interface only runs on Sun workstations under the SunView window system. WHAT OPERATING SYSTEM DEPENDENCIES ARE THERE? The code is generally pretty generic C, so running it on strange machines shouldn't be too much trouble, except for the dynamic loading modules. The Simulator should feel at home on most Berkeley Unix (BSD 4.2/4.3) based operating systems. In particular, if your system has an a.out.h file in /usr/include, it'll probably install easily. If your machine is based on AT&T System V, your object files are probably COFF format, and some changes need to be made. We are not running SunOS 4.0 here yet, so it is only known to run on SunOS 3.x systems. Again, the dynamic loading routines need a few changes to run under this operating system. If you have the simulator running on either System V or SunOS 4.0, please send me your patches, so that I can share them with everyone else. DO YOU HAVE AN X VERSION OF THE GRAPHIC INTERFACE? Someone here worked on a version of the graphic interface using X11 and the HP toolkit. It was close to working, but not quite debugged (as far as I can tell). Someone else (who will remain nameless for the moment) ported that code to X11 and the Athena toolkit. This code will probably be available soon. Stay tuned to this mailing list. IS THERE A VERSION AVAILABLE FOR MULTI-PROCESSORS? Well, yes and no. Version 4.0 was ported to the BBN Butterfly I. Unfortunately, this was one of the first things we did with the Butterfly, at a time when the programming environment was quite crude. (For those who know the Butterfly: this was before the existence of the Uniform System or the Streams library.) Getting it to run now is still possible, but it would require digging up a pile of little utility daemons and libraries and so forth, and, chances are, unless you are really serious about it, you'll give up! Perhaps only the original author (Mark Fanty) or I (Liudi Bukys) would really be able to do it, and we're both doing better things right now. If, after reading all this, you still want to try, contact me, and I'll gather the package up and send it to you. P.S. The back-propagation library doesn't run under this old Butterfly version. Of course, the current environment (Mach) on modern Butterflies is much better, so it's possible that someone here will port it there some time. To my knowledge, no one has ported a parallelized version to any of the other common multiprocessors (Sequent, Alliant, Encore, Inmos/Transputer, Intel/HyperCube). =============================================================================== Liudvikas Bukys <simulator-request@cs.rochester.edu>