This is the power system from section 6.2 of "Building Software for Simulation".
This is a very involved example: their are almost 2,300 lines of source code.
The makefile assumes that you are using the GNU C++ compiler. Run 'make' to build
the simulator. The shell script 'run.sh' is will execute all of the cases 
considered in section 6.2. The files in the gnuplot_scripts directory will produce
plots of frequency, power output from the generators, and initial and final voltages
as they appear in the book. You need, of course, gnuplot to use these files.

The data for the power system is contained in ieee118cdf.txt and ieee118cdf.ini. The
first file contains the data for the transmission lines, loads, etc. The second file 
contains the initial conditions for the simulator. Don't delete these file because the
simulator will not run without them.

This code differs slightly from what is described in the book. The ElectricalModel class
here is derived from the Hybrid class, and not the ode_system class as described in
"Building Software for Simulation". Rather, the ElectricalModel class contains the
ElectricalModelEqns class, which does inherit from the ode_system class and implements
the model's continuous equation. This simplifies the code in the various listeners that
record power, frequency, etc. by not requiring them to first get the state variables from
the Hybrid class before calculating whatever they want to record. Instead, all of these
steps are contained in the ElectricalModel's query methods.

