[GitHub] [spark] rwpenney commented on pull request #29938: [SPARK-33061][SQL] Expose inverse hyperbolic trig functions through sql.functions API

[GitBox <gi...@apache.org>]

rwpenney commented on pull request #29938:
URL: https://github.com/apache/spark/pull/29938#issuecomment-703730788


   As per my previous comments - I'm not suggesting that these inverse-hypoerboic functions will be widely used, but if `sql.functions` makes ordinary trig-functions available with their inverses, it ought to do the same for hyperbolic trig-functions. If there are concerns about `sql.functions` becoming rather bloated, perhaps at some point we may need a `sql.math.functions` or `sql.functions.math`?
   
   I have, personally, found use-cases where an inverse-sinh is quite handy in data-science applications, for compressing the dynamic range of signed quantities, in the same way `log` is often used for unsigned quantities. Hyperbolic-tangents appear sufficiently frequently in logistic regression models that having an inverse-tanh is also likely to be helpful.


----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

For queries about this service, please contact Infrastructure at:
users@infra.apache.org



---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscribe@spark.apache.org
For additional commands, e-mail: reviews-help@spark.apache.org