[tmva][sofie] Fix TMVA_SOFIE_ONNX tensor name for current PyTorch

[Neeraj-x0]

The tutorial hardcoded tensor name '16weight' which was generated by an older
PyTorch version. Current PyTorch Sequential modules produce tensors named
'0weight', '2weight', '4weight' (dot stripped by SOFIE).

Updated TMVA_SOFIE_ONNX.C to use '0weight' and regenerated Linear_16.onnx
using current PyTorch to keep tutorial and test model in sync.

Fixes: tutorial crash with runtime_error on GetTensorShape('16weight')

This Pull request:

Changes or fixes:

• Replaced hardcoded tensor name 16weight with 0weight in TMVA_SOFIE_ONNX.C
• Updated all print statements referencing the tensor name for consistency
• Regenerated tmva/sofie/test/input_models/Linear_16.onnx using current PyTorch

Checklist:

• tested changes locally
• updated the docs (if necessary)

This PR fixes #21545

[Copilot]

Pull request overview

This PR updates the TMVA SOFIE ONNX tutorial and its companion test artifact to align with tensor naming produced by current PyTorch/ONNX exports (e.g., 0.weight → 0weight after SOFIE name cleaning), fixing a runtime crash when querying tensor shapes/types.

Changes:

• Updated the tutorial macro to query 0weight instead of the obsolete 16weight.
• Updated tutorial print statements to match the new tensor name.
• Regenerated tmva/sofie/test/input_models/Linear_16.onnx using a current PyTorch export.

Reviewed changes

Copilot reviewed 1 out of 2 changed files in this pull request and generated 1 comment.

File	Description
tutorials/machine_learning/TMVA_SOFIE_ONNX.C	Updates the hardcoded tensor queried by the tutorial to match current PyTorch naming.
tmva/sofie/test/input_models/Linear_16.onnx	Updates the test ONNX model artifact to match current PyTorch export output.

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[sanjibansg]

LGTM!
Thanks, I would wait for the CI Jobs verification before we could merge this.

[github-actions]

Test Results

    20 files      20 suites   2d 22h 28m 7s ⏱️
 3 830 tests  3 823 ✅  1 💤  6 ❌
69 337 runs  69 274 ✅ 18 💤 45 ❌

For more details on these failures, see this check.

Results for commit f05a1c1.

♻️ This comment has been updated with latest results.

[guitargeek]

CI did not pass

[Neeraj-x0]

CI did not pass

Working on it — the fix requires regenerating Linear_16.onnx with a fixed seed and updating the reference values in TestCustomModelsFromONNX.cxx alongside the clang-format fixes. Will push shortly.

[guitargeek]

In that case the CI should pass with a clean build. I have triggered one, and also rebased your commits on top of ROOT master. Will merge once the CI passes.

[guitargeek]

Thanks!

[guitargeek]

Tests still fail even when doing a clean rebuild of everything in the CI. @Neeraj-x0, can you please take a look?