Xref: utzoo rec.games.frp:1800 comp.sources.wanted:2786
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From: gabai@steppenwolf.rutgers.edu (Gabai)
Newsgroups: rec.games.frp,comp.sources.wanted
Subject: Re: programs for frp
Message-ID: <2694@steppenwolf.rutgers.edu>
Date: 17 Dec 87 02:00:11 GMT
References: <2305@k.cc.purdue.edu> <9867@ut-sally.UUCP> <7236@sunybcs.UUCP> <3061@briar.Philips.Com>
Organization: Rutgers Univ., New Brunswick, N.J.
Lines: 39

If anyone is interested, one time I wrote up a simple little
10-line program:
  its purpose: instead of time-driven random encounter rolls
               it made event-driven random encounter rolls

  ex) 1/6 chance of encounter, every 4 hours for 15 days !!
      that's ninety die rolls! (egads)

   thus I applied some formula (if you are interested, 
   there's more:
     Amount_of_time_until_next_encounter
       := std_time_check * ln(1 - rnd(0..1))/ln(1 - std_prob_check)

so what, I lied about the program being 10 lines(it was on a pgm.
calc.)

ex)  t = (1/6 day) * ln (1-.12345678)/ln(1-1/6)
       ~ 50 minutes
     t = (1/6 day) * ln (1-.99)/ln(1-1/6)
       ~ 1 day (or larger)
just make sure:
  - you have appropriate real number capabities,
  - rnd(0..1) returns a random real number,
     with uniform distribution, in the range [0..1),
     cannot equal 1.000000... (should be obvious: ln(1-1)=undefined)

this makes it easier, with a time program running in background:

party: "we post guards at night, during a long journey"
computer: <boink> encounter at 3:45 during 3rd watch"
(much hacking/slashing or sneaking/hiding/BSing later)
computer: <boink (or whatever)>, 3 days later, at sunrise,
              just before the mountain pass.
etc.
-- 
Yours etc.,
Steven D. Gabai
gabai@nadc.arpa
gabai@paul.rutgers.edu