kll_sketch_get_rank_float

Extracts a rank value from a KLL float sketch given an input quantile value. The quantile can be a single value or an array.

Syntax

Python

from pyspark.sql import functions as sf

sf.kll_sketch_get_rank_float(sketch, quantile)

Parameters

Parameter	Type	Description
sketch	pyspark.sql.Column or str	The KLL float sketch binary representation.
quantile	pyspark.sql.Column or str	The quantile value(s) to lookup.

Returns

pyspark.sql.Column: The rank value(s) (between 0.0 and 1.0).

Examples

Example 1: Get rank from KLL float sketch

Python

from pyspark.sql import functions as sf
df = spark.createDataFrame([1.0,2.0,3.0,4.0,5.0], "FLOAT")
sketch_df = df.agg(sf.kll_sketch_agg_float("value").alias("sketch"))
sketch_df.select(sf.kll_sketch_get_rank_float("sketch", sf.lit(3.0))).show()

Output

+--------------------------------------+
|kll_sketch_get_rank_float(sketch, 3.0)|
+--------------------------------------+
|                                   0.6|
+--------------------------------------+