scipp / scipp/ess

General loading of sample orientation

Open
#574 5 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

essspectroscopy
Dominant language
Python
Stars
1
Forks
3
Avg merge
2d 11h
Merged PRs (30d)
17

Description

This issue also pertains to the file writer and maybe simulation framework. But I didn't know where else to put it.

The current workflow loads the sample orientation using the a3, a4 parameters of a McStas simulation: https://github.com/scipp/essspectroscopy/blob/fa79d4fb08c30c696aa077d25a927513f90059c1/src/ess/spectroscopy/indirect/workflow.py#L620-L622

This won't work for 'real' data. As the TODO comment suggests, we should probably use NXsample. See in particular sample_orientation and orientation_matrix. I don't know how those are meant to be used or why there are two different fields.

We already have some related code: https://github.com/scipp/scippneutron/blob/3d6664b861da0b770fed4c06d9162323f48f4d4f/src/scippneutron/conversion/tof.py#L552

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Read src/ess/spectroscopy/indirect/workflow.py around lines 620-622 and compare the related conversion in scippneutron's src/scippneutron/conversion/tof.py around line 552. Consult the NXsample documentation for sample_orientation and orientation_matrix, then determine how the workflow and file writer should load orientation for real data instead of relying on McStas a3/a4 parameters.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
data
Issue type
Feature
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
42/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.