Field: keep polarity on MagneticField re-initialisation - #15682
Merged
Conversation
This commit fixes MagneticField re-initialisation such that a field read back from a file keeps its polarity instead of being silently inverted. It: - applies the polarity convention once, in the constructors, instead of in CreateField() - leaves the stored factors untouched in CreateField(), which is the entry point for re-initialising a streamed object whose measured map is transient - adds a test comparing field vectors, not magnitudes, across a write/read round trip at solenoid, dipole and machine-compensator points This makes it possible to write a configured field to a ROOT file and read it back unchanged; until now the only correct way to recreate a field was to rebuild it from the GRP currents. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_0178JHAQ2biaX5ac9ThppBXi
shahor02
approved these changes
Aug 16, 2026
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
This commit fixes MagneticField re-initialisation such that a field read back from a file keeps its polarity instead of being silently inverted. It:
This makes it possible to write a configured field to a ROOT file and read it back unchanged; until now the only correct way to recreate a field was to rebuild it from the GRP currents.