On Tue, Jun 16, 2020 at 08:31:21AM +0100, Dean Rasheed wrote: > On Tue, 16 Jun 2020 at 06:00, Ashutosh Bapat > <ashutosh.ba...@2ndquadrant.com> wrote: > > > > Divison by zero is really undefined, 12345678 * 12345678 (just some > > numbers) is out of range of say int4, but factorial of a negative number > > has some meaning and is defined but PostgreSQL does not support it. > > > > Actually, I think undefined/out-of-range is the right error to throw here. > > Most common implementations do regard factorial as undefined for > anything other than positive integers, as well as following the > convention that factorial(0) = 1. Some implementations extend the > factorial to non-integer inputs, negative inputs, or even complex > inputs by defining it in terms of the gamma function. However, even > then, it is undefined for negative integer inputs.
Wow, they define it for negative inputs, but not negative integer inputs? I am curious what the logic is behind that. -- Bruce Momjian <br...@momjian.us> https://momjian.us EnterpriseDB https://enterprisedb.com The usefulness of a cup is in its emptiness, Bruce Lee
