pyspark.sql.functions.tuple_union_agg_double#

pyspark.sql.functions.tuple_union_agg_double(col, lgNomEntries=None, mode=None)[source]#

Aggregate function: returns the compact binary representation of the Datasketches TupleSketch that is the union of the double TupleSketch objects in the input column.

New in version 4.2.0.

Parameters

colColumn or column name: The column containing binary TupleSketch representations
lgNomEntriesColumn or int, optional: The log-base-2 of nominal entries (must be between 4 and 26, defaults to 12)
modeColumn or str, optional: The summary mode: “sum” (default), “min”, “max”, or “alwaysone”

Returns

Column: The binary representation of the merged TupleSketch.

See also

pyspark.sql.functions.tuple_sketch_agg_double()
pyspark.sql.functions.tuple_union_double()

Examples

>>> from pyspark.sql import functions as sf
>>> df1 = spark.createDataFrame([(1, 10.0), (2, 20.0)], ["key", "value"])
>>> df1 = df1.agg(sf.tuple_sketch_agg_double("key", "value").alias("sketch"))
>>> df2 = spark.createDataFrame([(3, 30.0), (4, 40.0)], ["key", "value"])
>>> df2 = df2.agg(sf.tuple_sketch_agg_double("key", "value").alias("sketch"))
>>> df3 = df1.union(df2)
>>> df3.agg(sf.tuple_sketch_estimate_double(sf.tuple_union_agg_double("sketch"))).show()
+---------------------------------------------------------------------+
|tuple_sketch_estimate_double(tuple_union_agg_double(sketch, 12, sum))|
+---------------------------------------------------------------------+
|                                                                  4.0|
+---------------------------------------------------------------------+