GSL within Public Domain Software

[Lowell Johnson <ldjohn at usgs dot gov>]

Hello.

Our team develops image analysis software for the USGS.  For many years this
software has made use of mathematical routines that have been extracted from
various public domain packages as well as some "home-grown" algorithms.  Now we
are trying to incorporate available open source libraries to a larger extent.

My past experience led me to first consider LAPACK and FFTPACK.  But we only
need a small portion of LAPACK's capability, and it doesn't cover many of the
additional numerical methods we apply.

Last week I came across the GSL and thought that, even though it is in the
development stage, it will cover a large portion of our requirements for a
general purpose numerical library.  In addition the GSL is lightweight compared
with the likes of LAPACK, so it is not asking so much to expect our external
users to build it.

The question is, since our software is from the government (public domain),
what are the legalities of linking with a GPL'ed library?  We distribute both
the source code and binaries (for supported platforms).  I understand the GPL
concerns regarding proprietary software using GPL libraries, but since public
domain software is source distributed, it seems that the intent of the GPL is
fairly covered.

We will have to discuss the situation with government officials as well, but I
wanted to give you people a chance to respond first.  I have read the GPL/LGPL
discussions, so I understand those concerns.  But it would be unfortunate if
we have to abandon incorporation of the GSL due to GPL restrictions.

Thanks for any comments or suggestions.

-- 
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Lowell D. Johnson       ldjohn@usgs.gov
Software Engineering
Raytheon Systems
EROS Data Center
47914 252nd Street, Mundt Federal Bldg
Sioux Falls, SD 57198
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