Path: utzoo!attcan!telly!lethe!yunexus!ists!helios.physics.utoronto.ca!physics.utoronto.ca!neufeld
From: neufeld@physics.utoronto.ca (Christopher Neufeld)
Newsgroups: comp.sys.apple2
Subject: Re: Accrete
Message-ID: <1990Nov30.221510.15850@helios.physics.utoronto.ca>
Date: 1 Dec 90 03:15:11 GMT
References: <238@generic.UUCP>
Organization: University of Toronto Physics/Astronomy/CITA
Lines: 37

In article <238@generic.UUCP> taob@pnet91.cts.com (Brian Tao) writes:
>
>    I also downloaded this simulation, and it is certainly interesting to read
>through the reams of data it pours out.  Have you been able to find seeds
>which will create a system with an Earth-type planet (a "class M" planet)? 
>
>If you find any interesting seeds, please
>post them here!
>
   I found an interesting one. The seeds: 3040, 12042, -9948, 31225
forms a system with a few "Mercury"s, a "Venus", an "Earth" (pressure's
a bit low, but easily in the liveable range), and oodles of gas giants,
some quite huge.
   Question: I noticed that the first eight simulations I ran came out
pretty well the same. In particular, the primary's mass never changed. I
found out that the program always came up with the first seed either
-17095 or -17094. Subsequent seeds may have been similar from run to run
also. I've taken to running a one line random number generator to
produce the seeds, then running ACCRETE. I've noticed this with other
programs also. Is my GS unusual in failing to reseed correctly? Has it
something to do with the keyboard buffer being active, and so the GETKEY
sequence doesn't get a chance to increment the random number seed in
zero page, since the keyboard is never "idle"?

>    I'm surprised it takes so long on a //c  I'm running it on my GS, and it
>takes about 30 minutes on average per simulation.  This is at the standard 2.8
>MHz clock speed.  From that figure, a 1-MHz machine should finish it in about
>90 minutes or so.
>
   That's the same time as it took on my machine (an unaccelerated GS).


-- 
 Christopher Neufeld....Just a graduate student  |
 neufeld@helios.physics.utoronto.ca    Ad astra! |  S = k log W
 cneufeld@{pnet91,pro-micol}.cts.com             |    Boltzmann's epitaph
 "Don't edit reality for the sake of simplicity" |