PostgreSQL/Analytical Functions/width bucket

width_bucket(op numeric, b1 numeric, b2 numeric, count int)

--width_bucket(op numeric, b1 numeric, b2 numeric, count int) 
--Return the bucket to which operand would be assigned in an equidepth histogram with count 
--buckets, an upper bound of b1, and a 
--lower bound of b2 

postgres=#
postgres=# select width_bucket(5.35, 0.024, 10.06, 5);
 width_bucket
--------------
            3
(1 row)
postgres=#