20 lines
673 B
PL/PgSQL
20 lines
673 B
PL/PgSQL
-- Getis-Ord's G
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-- Hotspot/Coldspot Analysis tool
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CREATE OR REPLACE FUNCTION
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CDB_GetisOrdsG(
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subquery TEXT,
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column_name TEXT,
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w_type TEXT DEFAULT 'knn',
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num_ngbrs INT DEFAULT 5,
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permutations INT DEFAULT 999,
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geom_col TEXT DEFAULT 'the_geom',
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id_col TEXT DEFAULT 'cartodb_id')
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RETURNS TABLE (z_score NUMERIC, p_value NUMERIC, p_z_sim NUMERIC, rowid BIGINT)
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AS $$
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from crankshaft.clustering import Getis
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getis = Getis()
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return getis.getis_ord(subquery, column_name, w_type, num_ngbrs, permutations, geom_col, id_col)
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$$ LANGUAGE plpythonu VOLATILE PARALLEL UNSAFE;
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-- TODO: make a version that accepts the values as arrays
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