Language Challenge 2000

[bvoh at sdynamix.com]

		Language Challenge 2000

The entire onboard software for the Apollo Lunar Landing Mission was
about 10% the size of today's typical word processor -- a huge regress
by any standard. For a measure of progress in scientific software you
are invited to participate in a comparative test by solving a real world
problem in the language of your choice.

Find the optimal initial angle for a trajectory to reach a target at
2000 m to within .5 m. The equations of motion are given by,

           	mx" + Dcos(alfa) = 0
            	my" + Dsin(alfa) + mg = 0
where
            	D = .5*Cd*A*rho(y)*v^2     alfa = atan(y'/x')

and rho() is a variable atmospheric density w.r.t. altitude.

Parameters: 	m = 20 kg   Cd = .3   A = .02 m^2   g = 9.80665 m/s^2
Initial values:	x = 0 m    y = 0 m   v = 180 m/s   alfa = 40 deg

Rules:  Solution  must be general; trial and error methods based on
apriori knowledge of the solution range do not qualify. Feel free to use
external software resources as well as the "Trajectory" example on our
"Application profiles" page as a convenient guideline. 

Criteria:

	a)  Execution time
	b)  Size of executable

Submit: Executable module (show final angle and distance), main program
text file and indicate the integration and optimization algorithms used.
e.g. Levenberg-Marquardt (netlib). All entries must be received by March
31, 2000.

The best entry in each language will be posted on our site to serve as a
barometer for those pondering what language to choose for their
technical computing. It might also double as a place where flame war
enthusiasts can calibrate their rhetoric against the realities of
feasible solutions. The overall winner will receive:

	Compaq Visual Fortran V6.1 -- Professional Edition
	SDX Modeling and Simulation Software V3.0

as a special recognition for demonstrated skills in crafting the fastest
solution with a smallest footprint.

Questions regarding the contest should be directed to info at sdynamix.com
with Contest 2000 in the "Subject" line.

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Modeling * Simulation * Analysis
http://www.sdynamix.com
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