Format initial string to specific precision, so rounding works.#4159
Merged
enebo merged 1 commit intojruby:masterfrom Oct 12, 2016
Merged
Format initial string to specific precision, so rounding works.#4159enebo merged 1 commit intojruby:masterfrom
enebo merged 1 commit intojruby:masterfrom
Conversation
The logic in our double-based sprintf logic attempts to round values manually by inspecting a long-form version of the double. If we need to round, and the next digit is a five, it will round toward zero (truncate) iff that five is the last digit in the long unrounded string. This appears to have been an attempt to mimic C printf's behavior of rounding "true half" to even in the presence of inaccurately-represented IEEE754 decimals. This commit changes the pre-formatting to actually format with the specified precision, allowing NumberFormat's default HALF_EVEN logic to to the work for us. Fixes jruby#4157.
This was referenced Oct 30, 2016
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
The logic in our double-based sprintf logic attempts to round
values manually by inspecting a long-form version of the double.
If we need to round, and the next digit is a five, it will round
toward zero (truncate) iff that five is the last digit in the long
unrounded string. This appears to have been an attempt to mimic
C printf's behavior of rounding "true half" to even in the
presence of inaccurately-represented IEEE754 decimals.
This commit changes the pre-formatting to actually format with the
specified precision, allowing NumberFormat's default HALF_EVEN
logic to to the work for us.
Fixes #4157.