Weijun-H opened a new issue, #12247:
URL: https://github.com/apache/datafusion/issues/12247

   ### Is your feature request related to a problem or challenge?
   
   Calculates [Shannon 
entropy](https://en.wikipedia.org/wiki/Entropy_(information_theory)) of a 
column of values.
   
   ### Describe the solution you'd like
   
   ```
   D CREATE TABLE entropy (vals UInt32,strings String);
   D INSERT INTO entropy VALUES (1, 'A'), (1, 'A'), (1,'A'), (1,'A'), (2,'B'), 
(2,'B'), (2,'C'), (2,'D');
   D
   D SELECT entropy(vals), entropy(strings) FROM entropy;
   ┌───────────────┬──────────────────┐
   │ entropy(vals) │ entropy(strings) │
   │    double     │      double      │
   ├───────────────┼──────────────────┤
   │           1.0 │             1.75 │
   └───────────────┴──────────────────┘
   
   ```
   
   ### Describe alternatives you've considered
   
   _No response_
   
   ### Additional context
   
   https://duckdb.org/docs/sql/functions/aggregates#entropyx
   
https://clickhouse.com/docs/en/sql-reference/aggregate-functions/reference/entropy


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