glen/dyna3
1
0
Fork 1
Code Issues 26 Pull requests 1 Projects 1 Releases 2 Wiki Activity Actions

Adjust normalization step of nudge routine #43

Merged
glen merged 3 commits from normalize-by-contracting into main 2025-02-06 22:53:42 +00:00
Conversation 0 Commits 3 Files changed 1 +13 -6
Vectornaut commented 2025-02-05 21:37:58 +00:00
Collaborator
Copy link

The brach to be merged partially addresses issue #42 by changing the way we normalize element representations after stepping them in a straight line through configuration space during a nudge. On the main branch, we rescale the whole representation vector. On the branch to be merged, we instead contract the representation vector toward the last coordinate axis by rescaling the spatial and curvature components.

Improvement in leakage

This change reduces the directional leakage described in #42. For a quantitative comparison, I used the reproduction prodcedure from that issue, holding W until the second coordinate of Deimos had increased by 4 units (from 0.6 to 4.6). During this motion, the third coordinate changed by 0.158 units on the main branch, but only 0.007 units on the branch to be merged. In other words, this pull request decreased drift by roughly a factor of 20.

Neutral changes in oscillation and jitter

This change makes oscillation and jitter happen differently during the reproduction procedures from #42, but I wouldn't describe them as being better or worse.

The brach to be merged partially addresses issue #42 by changing the way we normalize element representations after stepping them in a straight line through configuration space during a nudge. On the main branch, we rescale the whole representation vector. On the branch to be merged, we instead contract the representation vector toward the last coordinate axis by rescaling the spatial and curvature components. ### Improvement in leakage This change reduces the directional leakage described in #42. For a quantitative comparison, I used the [reproduction prodcedure](issues/42#user-content-leakage) from that issue, holding **W** until the second coordinate of Deimos had increased by 4 units (from 0.6 to 4.6). During this motion, the third coordinate changed by 0.158 units on the main branch, but only 0.007 units on the branch to be merged. In other words, this pull request decreased drift by roughly a factor of 20. ### Neutral changes in oscillation and jitter This change makes oscillation and jitter happen differently during the reproduction procedures from #42, but I wouldn't describe them as being better or worse.
Vectornaut added 3 commits 2025-02-05 21:38:00 +00:00 
Uniformly contract spatial and curvature components. This preserves the
centers of spheres, but alters their curvatures. It should preserve
planes entirely.
We don't need to explicitly allocate scratch space.
glen merged commit 25017176fd into main 2025-02-06 22:53:42 +00:00
glen deleted branch normalize-by-contracting 2025-02-06 22:53:42 +00:00
Sign in to join this conversation.
Reviewers
No reviewers
Labels
Clear labels   
bug

Something is not working

  
duplicate

This issue or pull request already exists

  
enhancement

New feature

  
prospective

this becomes an issue once a particular feature is implemented or pull request is merged

  
question

More information is needed

  
todo

Planned step in implementation

  
wontfix

This won't be fixed

No labels
bug
duplicate
enhancement
prospective
question
todo
wontfix
Milestone
Clear milestone
No items
No milestone
Projects
Clear projects
No items
No project
Assignees
Clear assignees
No assignees
1 participant
Notifications
Due date
The due date is invalid or out of range. Please use the format "yyyy-mm-dd".

No due date set.

Dependencies

No dependencies set.

Reference: glen/dyna3#43
No description provided.
Delete branch "normalize-by-contracting"

Deleting a branch is permanent. Although the deleted branch may continue to exist for a short time before it actually gets removed, it CANNOT be undone in most cases. Continue?