réplica de
https://github.com/rspamd/rspamd.git
synced 2024-08-19 02:10:31 +02:00
46 líneas
983 B
Lua
46 líneas
983 B
Lua
--[[ https://en.wikipedia.org/wiki/Normal_distribution ]]
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-- The Box–Muller method
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local function gaussian(mean, variance)
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local U = math.random()
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local V = math.random()
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return math.sqrt(-2.0 * variance * math.log(U)) *
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math.cos(2.0 * math.pi * V) + mean
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end
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local function mean(t)
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local sum = 0
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local count = #t
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for i = 1, count do
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sum = sum + t[i]
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end
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return sum / count
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end
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local function std(t, mean)
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local squares = 0.0
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for i = 1, #t do
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local deviation = math.abs(mean - t[i])
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squares = squares + deviation * deviation
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end
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local variance = squares / #t
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return math.sqrt(variance)
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end
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local function do_the_call()
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local t = {}
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local mu = 34.0
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local sigma = 10.0
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for i = 1, 5 do
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table.insert(t, gaussian(mu, sigma))
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end
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return string.format("Got mean: %1.5f, mu: %1.5f\nstd deviance:%1.5f, expected: %1.5f",
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mean(t), mu,
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std(t, mu), math.sqrt(sigma))
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end
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math.randomseed(os.time())
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return do_the_call
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