Re: gEDA-user: Ngspice vs. Gnucap vs. ???

[Ales Hvezda <ahvezda@seul.org>]

[ Ales here, I'm reposting this since majordomo didn't recognize the
  e-mail as being subscribed to the geda-dev mailinglist. This one slipped
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-- Cut here --
From: John Dalton <john.dalton@bigfoot.com>

> I thought spice was bsd. have the others been rewritten or am I off base?

My understanding is that the current version of Berkeley SPICE is not BSD, but
is free for non-commercial use only.  Most people ignore these restrictions
(or have licensed it from Berkeley?).  SPICE is not suitable for those who
want to simultaneously obey the law and require that software be available
for all fields of endeavour.

Some caveats on the above.
1) Earlier versions may be under a different license.
2) I can't find an explicit license file for SPICE anywhere in the source
   distribution, or on the web.

I'm basing the above on an email in the debian archives:
  http://lists.debian.org/debian-devel/1999/debian-devel-199911/msg01989.html

Also, it is interesting to look at the copyright notices in the source files
for the SPICE 3f4 distribution.

Here is the copyright message from the source file 'main.c' in the
SPICE 3f4 source:

  /**********
  Copyright 1990 Regents of the University of California.  All rights reserved.
  Author: 1986 Wayne A. Christopher, U. C. Berkeley CAD Group 
  **********/
   
No mention of BSD license conditions here.  I guess 'written by Berkeley' does
not equate to 'released under the BSD'.

Other bits (src/lib/mac and some jfet models) are copyright Macquarie Univeristy:

  /**********
  Copyright 1992
  Author: 1992 Anthony E. Parker, Macquarie University, Sydney Australia.
  **********/

Again, no mention of the BSD.

To complicate things, the sparse matrix library used by SPICE 3f4 code *is*
released under the BSD:

**IN SUMMARY**: SPICE is not free, though a small part of the code base (380k
out of 10000k) is released under the BSD.

If you have any information to the contrary, please reply to this message
and correct me!


As far as I know, ngspice is currently BSD SPICE with bug fixes and recent patches
applied.  It aims to be a GPLd SPICE, but the current release requires a major
rewrite to eliminate all Berkeley code to achieve this aim.  Since ng-spice
is a Berkeley derivative, it operates under the same restrictions as Berkeley SPICE.


GnuCap is a clean room implementation of SPICE.  It is GPLd and satisfied the
Free Software Guidelines.


I tried the various spices about a year ago (under Debian).  A summary,
of my experiences is:
--- ngspice: I couldn't get it to run.
--- SPICE+Nutmeg: It worked, though it sometimes didn't convergence.
--- GnuCap (was ACS): It worked well, but some models I required had
  not yet been implemented.

Regards
John