Crash post_processing script update

[dakhare-creator]

PhysicsNeMo Pull Request

Description

Checklist

• I am familiar with the Contributing Guidelines.
• New or existing tests cover these changes.
• The documentation is up to date with these changes.
• The CHANGELOG.md is up to date with these changes.
• An issue is linked to this pull request.
• If I am implementing a new model or modifying any existing model, I have followed the Models Implementation Coding Standards.

Dependencies

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[greptile-apps]

Greptile Summary

This PR enhances crash simulation post-processing to support computing MSE (position, velocity, acceleration) across multiple test samples. The changes include refactored Python script to handle both single-sample and multi-sample analysis, a new Jupyter notebook for comparing L2 errors across runs, and an updated shell script.

Major Changes:

• Refactored compute_probe_kinematics.py to support multi-sample analysis with new functions for discovering runs, computing squared errors, and aggregating MSE
• Added new notebook compare_plots.ipynb for comparing L2 error metrics across different model runs
• Updated run_post_processing.sh to process multiple samples using parent directory parameters

Critical Issues:

• run_post_processing.sh has a bash syntax error on line 5 (space after = in variable assignment) that will prevent the script from running
• Line 16 references undefined variables $pred_path and $exact_path that will cause the script to fail

Important Files Changed

Filename	Overview
examples/structural_mechanics/crash/post_processing/run_post_processing.sh	Updated script to process multiple samples, but has critical bash syntax error on line 5 and undefined variables on line 16 that will prevent execution
examples/structural_mechanics/crash/post_processing/compute_probe_kinematics.py	Added new functions to compute MSE across multiple samples, refactored main into single/multi-sample variants - implementation looks correct
examples/structural_mechanics/crash/post_processing/compare_plots.ipynb	New notebook for comparing L2 error across runs - straightforward plotting logic with placeholder directory names to be filled by user

_{Last reviewed commit: 3019254}

[greptile-apps]

_{3 files reviewed, 2 comments}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

Space after = causes bash syntax error - variable won't be set

Suggested change

	dir_path= /path/to/output/directory
	dir_path=/path/to/output/directory

[greptile-apps]

$pred_path and $exact_path are undefined - this line will fail

Suggested change

	python plot_cross_section.py --pred_dir $pred_path --exact_dir $exact_path --output_file $dir_path/post_processing_results/cross_section.png
	python plot_cross_section.py --pred_dir $dir_path/predicted_vtps --exact_dir $dir_path/exact_vtps --output_file $dir_path/post_processing_results/cross_section.png