> On 4 Apr 2016, at 21:28, Stefan Zobel <splitera...@gmail.com> wrote: > > Hi Tagir, > > good catch! I like the proposal. >
Me too. +1. Extra bonus points to test, in addition to the tested characteristics, that the boxed/converted elements remain sorted/distinct :-) >> >> (different longs can be converted into the same double, so DISTINCT is >> not preserved here; not sure whether this is possible for ints) >> > > I think IntStream.asDoubleStream() can also preserve DISTINCT as > different ints can't be mapped to the same double. > Yes, there are 53 bits to play with, which is more than enough to exactly represent the full range of int values. Paul. > > Math.ulp((double) Integer.MIN_VALUE) ~ 4.7E-7 > > in contrast to > > Math.ulp((double) Long.MIN_VALUE) = 2048.0 > > > So there are more than enough doubles in the vicinity of large int > values. It's only when ulp get's >= 1.0 that distinct integral values > need to be mapped to the same double (that happens between 1.0E15 and > 1.0E16 for longs). Please anyone correct me if I'm wrong. > > > Regards, > Stefan >
