Skip to content

fix: weights should not be raised to the power n in the n-th moment calculation #3729

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
wants to merge 2 commits into
base: main
Choose a base branch
from
Open

fix: weights should not be raised to the power n in the n-th moment calculation #3729

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
823e69c
fix moment calculation
ikrommyd Nov 13, 2025
0195c4b
docstring
ikrommyd Nov 13, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 2 additions & 2 deletions src/awkward/operations/ak_moment.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -73,7 +73,7 @@ def moment(

Passing all arguments to the reducers, the moment is calculated as

ak.sum((x*weight)**n) / ak.sum(weight)
ak.sum(x**n * weight) / ak.sum(weight)

The `n=2` moment differs from #ak.var in that #ak.var also subtracts the
mean (the `n=1` moment).
Expand Down Expand Up @@ -148,7 +148,7 @@ def _impl(
attrs=ctx.attrs,
)
sumwxn = ak.operations.ak_sum._impl(
(x * weight) ** n,
(x**n) * weight,
axis,
keepdims,
mask_identity,
Expand Down
Loading