pyspark.sql.functions.tuple_sketch_estimate_double#

pyspark.sql.functions.tuple_sketch_estimate_double(col)[source]#

Returns the estimated number of distinct keys from a Datasketches TupleSketch with double summaries.

New in version 4.2.0.

Parameters

colColumn or column name: The column containing a binary TupleSketch representation

Returns

Column: The estimated cardinality.

See also

pyspark.sql.functions.tuple_sketch_agg_double()
pyspark.sql.functions.tuple_sketch_summary_double()

Examples

>>> from pyspark.sql import functions as sf
>>> df = spark.createDataFrame([(1, 10.0), (2, 20.0), (2, 30.0)], ["key", "value"])
>>> df.agg(sf.tuple_sketch_estimate_double(
...     sf.tuple_sketch_agg_double("key", "value"))).show()
+--------------------------------------------------------------------------+
|tuple_sketch_estimate_double(tuple_sketch_agg_double(key, value, 12, sum))|
+--------------------------------------------------------------------------+
|                                                                       2.0|
+--------------------------------------------------------------------------+