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Old September 24th 07, 06:05 AM posted to rec.radio.amateur.antenna
[email protected] jimlux@earthlink.net is offline
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First recorded activity by RadioBanter: Jan 2007
Posts: 61
Default Speedup NEC-Engine, using multiple CPU-Cores

On Sep 23, 7:47 pm, Roy Lewallen wrote:
wrote:



I was recently told that the non-commercial NEC-4 license doesn't
include source code. I haven't confirmed this, but it's something you
should investigate before purchasing an NEC-4 license if you intend to
modify the source code.


My non-commercial copy included Source. I can't imagine that getting
only precompiled versions would be particularly useful, unless they're
willing to make a whole raft of versions (more than you get with the
release I got) with various values for the maximum segments, etc.

OTOH, LLL did just change management, so they assigned all the
licenses from UC to the new LLL management consortium, and maybe they
changed how it works for new licenses. The website still says to make
your check payable to Regents of UC

http://www.llnl.gov/ipac/technology/...titles/nec.php

And someday, Gerry Burke is going to retire, and whoever picks it up
from him may not be as willing and helpful to, for instance, recompile
peculiar versions for you.


You'll also, of course, need a Fortran compiler capable of compiling a
multi-threaded application.

That would be if you're doing finegrained parallelism (e.g. using a
multiprocessor BLAS library. Several of the strategies (dividing it
up by frequency) could actually be done by a reasonably simple shell
script/batch file that fires off the executable on different
processors with different input files. For my own NEC on a Cluster
runs, I've done the separate runs on separate machines and merge the
output files in post processing strategy.

Roy Lewallen, W7EL