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0 votes
asked by (12 points)
X-Plane apparently randomizes small adjustments to add realism.  I'm researching an accident that involves flying in near-stall conditions.  I fly an XP10 sim Electra L188 under a program harness.  It's taken several thousand iterations so far for one solution, because the closer I get to the optimal answer the larger the relative error that's introduced by the randomizing.  This means I have to run dozens of runs to determine how to make my next input tweak, averaging to eliminate randomize-introduced jiggles.  I estimate the second solution I want would take a couple orders of magnitude more sim runs.  Can I turn off the XP code that introduces randomizing so I get exactly the same run every time?

1 Answer

0 votes
answered by (19.3k points)
You could set the weather and time seeds by launching from the command line so they would be consistent.
commented by (12 points)
I don't see anything about being able to set seeds from the command line --help or web search.  Can you give me a slightly expanded clue?

Assuming I could set the seeds, this would work only if I restart XP each time I do a run.  Otherwise for each following pass the random values would be different.

The whole arrangement consists of my control program and its info box, along with XP, framed in a screen capture.  If I set up the control and screen capture, I might be able to script XP iterations.  Hmmm
commented by (19.3k points)
For our in house testing, we use a python script that launches X-Plane with:

--weather_seed=1

--time_seed=1

(I assume there are other seeds but I do not have specifics on what changes between them. Starting with seed 1 each time at least will give you consistent time/weather to begin with. We also use FDR files in our FPS testing to control more variables.)
commented by (12 points)
Thanks.  I'm pretty much a  noob at python.  I'll fiddle with it.  My main concern is that this may be a minor part of the randomizer noise.  What I'd really like to do is stop the code entirely, but having written some sim stuff I'm pretty confident it's happening at a low level and very likely not a configurable option.
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