On Wed, 3 Mar 2021 07:20:03 GMT, Joe Darcy <da...@openjdk.org> wrote:
> I considered @stuart-marks previous suggestion during the code review of > JDK-8261123 to include a more explicit discussion of why, say, different > representations of 2 should not be regarded as equivalent. After > contemplating several alternatives, I didn't find anything simpler than > Stuart's 2/3 example so I used that as seen in the diff. > > A short digression, BigDecimal supports both fixed-point style and > floating-point style rounding. Floating-point rounding primarily replies on > the number of precision digits, regards of their scale, while fixed-point > style rounding prioritizes the scale. The number of digits of eventual output > is a function of number number of digits in the inputs and the number of > precision digits in a floating-point style rounding. A floating-point style > rounding has a preferred scale, rather than a fixed scale based on the > inputs. The fixed-point style divide method used in the example has a scale > based on the dividend, allowing a relatively simple expression to show a > distinction between 2.0 and 2.00. This pull request has now been integrated. Changeset: a1181852 Author: Joe Darcy <da...@openjdk.org> URL: https://git.openjdk.java.net/jdk/commit/a1181852 Stats: 19 lines in 1 file changed: 11 ins; 0 del; 8 mod 8261862: Expand discussion of rationale for BigDecimal equals/compareTo semantics Reviewed-by: smarks, bpb ------------- PR: https://git.openjdk.java.net/jdk/pull/2804
