32 lines
614 B
Erlang
32 lines
614 B
Erlang
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-module(probabilistic_choice).
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-export([test/0]).
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-define(TRIES, 1000000).
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test() ->
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Probs =
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[{aleph,1/5},
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{beth,1/6},
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{gimel,1/7},
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{daleth,1/8},
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{he,1/9},
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{waw,1/10},
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{zayin,1/11},
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{heth,1759/27720}],
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random:seed(now()),
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Trials =
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[get_choice(Probs,random:uniform()) || _ <- lists:seq(1,?TRIES)],
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[{Glyph,Expected,(length([Glyph || Glyph_ <- Trials, Glyph_ == Glyph])/?TRIES)}
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|| {Glyph,Expected} <- Probs].
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get_choice([{Glyph,_}],_) ->
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Glyph;
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get_choice([{Glyph,Prob}|T],Ran) ->
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case (Ran < Prob) of
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true ->
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Glyph;
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false ->
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get_choice(T,Ran - Prob)
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end.
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