17 lines
489 B
SQL
17 lines
489 B
SQL
-- continuous uniform distribution has kurtosis = -6/5, skewness = 0.0
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-- http://mathworld.wolfram.com/UniformDistribution.html
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set client_min_messages to ERROR;
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With dist As (
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SELECT random()::numeric As val
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FROM generate_series(1,5000000) t
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)
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SELECT
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-- does random dist values match within 1% of known values
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abs(CDB_Kurtosis(array_agg(val)) + 1.20) < 1e-2 As kurtosis,
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abs(CDB_Skewness(array_agg(val)) - 0) < 1e-2 As skewness
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FROM dist;
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set client_min_messages to NOTICE;
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