Hat Trick Nbody Simulator
By William Olson and Jason Dittmann
Version 1.0
Copyright 2010 - GNU General Public License v3
http://code.google.com/p/hattrick-nbody/

TO COMPILE:
	Simply type 'make'.
	This uses gcc by default.  To change
	Edit GCC in the Makefile.
	
REQUIREMENTS:
	GNU Scientific Library:  Routines for integration of ODEs.  On
	Ubuntu/Debian install with:
		sudo apt-get install libgsl0-dev

TO RUN:
	Input format:
		./hattrick baseSys
		./hattrick baseSys n m1 r1 ... mn rn

	Where:
		baseSys: Name of the file specifying the base system.
		n (optional): Number of perturbing bodies.
		mn (optional): Mass of the nth perturbing body.
		rn (optional): Radius of the nth perturbing body.

	Base system file format:
		n t0 t1 h0 h1 accr printSkip stepType
		m1 x1 y1 z1 vx1 vy1 vz1
		m2 x2 y2 z2 vx2 vy2 vz2
			...
		mn xn yn zn vxn vyn vzn


	Where:
		n: Number of bodies in the base system.
		t0: Initial system time.
		t1: Final system time.
		hmin: Minimum time step.
		hmax: Max time step.  Also the initial step size.
		accr: Accuracy paramater.
		skipPrint:
			>0 to specify the time skipped between prints.
			=0 to print on orbits only.
			<0 to print just the closest orbit time.
		stepType: 0 for rk45, 1 for rk8pd, 2 for bsimp.


Examples:
	./hattrick
		Prints the help shown above.
		
	./hattrick sunearth.dat
		This will run a integration of the Sun and Earth.	
	
	./hattrick sunearth.dat 1 9.5492E-4 5.204267 > out.txt
		This will run a integration of the Sun, Earth and a circularized
		Jupiter and direct the ouput into 'out.txt'.