The Numerical Electromagnetics Code (NEC-2) is a comprehensive package for the analysis of the electromagnetic properties of structures. It can analyse radiating properties i.e. antenna gain, as well as scattering properties (radar cross section) of structures. NEC-2 was originally written in FORTRAN.

NEC2++ is an extensive rewrite of NEC-2 in C++ by Tim Molteno. This work was helped tremendously by the work of N. Kyriazis who ported NEC-2 to C. The new portions of code are licensed under the GNU Public License (GPL).

Latest version is 1.2.9 [31 July 2008]

Check out the NEC Forum for release notes and more

• Download Linux executable for the latest version 31 July 2008 [500 kB tar.bz2]
• Download source code for the latest version 31 July 2008 [116 kB tar.bz2]
• Download a Windows executable [312 kB zip], created with MinGW
• Download a Windows Code Distribution [260 kB zip], including a Visual Studio Project file.
• A very basic attempt at a users guide will be available soon.

Usage

To use nec2++, after installation

usage: nec2++ [-i input-file-name] [-o output-file-name]
       -g: print maximum gain to stdout.
       -b: Perform NEC++ Benchmark.
       -s: print results to standard output.
       -c: print results in comma-separated-value (CSV) format,
           this options is used in conjunction with (-s) above.
       -h: print this usage information and exit.
       -v: print nec2++ version number and exit.

The output file name is optional. If it is not specified, a file will be created in the same directory as the input file and with an extension .out.

Compilation on Linux/Unix

Decompress the source-code archive, and issue the following commands. This should work on systems with a C++ compiler (almost all systems)

tar -jxf necpp_latest.tar.bz2
cd necpp_31 July 2008_short
make -f makefile.dist
make -f makefile.dist install

Compilation on Windows

Decompress the Windows Code Distribution, and build the Visual Studio project inside the win32 subdirectory

Links

• The NEC Archives.
• Hints for Compiling Nec2++ on Mac OS X
• AMOD: An excellent introduction to using NEC.
• NEC error messages

Building using Autoconf

To build libnecpp, and use NEC from a C API, you need to use autoconf and friends -- to install these on Debian linux, simply type

apt-get install automake libtool

To build the library, download the autoconf distribution [1 MB] and issue the following commands:

tar -zxf necpp-1.2.9.tar.gz
cd necpp-1.2.9
./configure
make
make install

Release Notes are available from the NEC Forum

Notes

In the very near future, nec2++ will depend on the ATLAS. To install this use the following commands under DEBIAN linux (http://www.debian.org).

	apt-get install atlas3-base atlas3-headers atlas3-base-dev
	apt-get install refblas3-dev lapack3-dev lapack3-doc

For installation on other operating systems, you should look at the ATLAS page.