get pairwise-sum accuracy for cumsum (fix #9648) #9650
Merged
Conversation
This file contains 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
|
Probably worth backporting too. |
|
Aside from needing to address the (quite serious) element type problem that has already been lurking in master, this looks very nice! |
|
We could define something like: _cumsum_type{T<:Number}(v::AbstractArray{T}) = typeof(r_promote(AddFun, zero(T)::T))
_cumsum_type(v) = typeof(r_promote(AddFun, v[1]))to use the same type as |
|
That's very reasonable, actually. Merge this whenever you're happy. |
|
Note also that |
stevengj
added a commit
that referenced
this pull request
Jan 7, 2015
get pairwise-sum accuracy for cumsum (fix #9648)
stevengj
added a commit
to stevengj/julia
that referenced
this pull request
Jan 7, 2015
…use same codepath for 1d arrays (see discussion in JuliaLang#9650)
stevengj
added a commit
that referenced
this pull request
Jan 18, 2015
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
This fixes #9648 (our
cumsumfunction had naive-summation accuracy despite using a pairwise-like algorithm). No performance impact as far as I can tell (difference from oldBase.cumsum_pairwiseis negligible).