fix: linear-interpolation

[binary69]

Closes #160

Fixes the linear interpolation in PhaseShiftedSequenceInterpolator.interpolate and SequenceInterpolator.interpolate

[gitnotebooks]

Review these changes at https://app.gitnotebooks.com/sensorium-competition/experanto/pull/161

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

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[Copilot]

Pull request overview

Fixes linear interpolation time calculations when start_time != 0 for both SequenceInterpolator and PhaseShiftedSequenceInterpolator, and extends tests to cover non-zero start times (issue #160).

Changes:

• Add start_time when computing times_lower/times_upper in SequenceInterpolator.interpolate (linear mode).
• Add start_time and per-signal phase shifts to times_lower/times_upper in PhaseShiftedSequenceInterpolator.interpolate (linear mode), and adjust numerator computation accordingly.
• Expand linear interpolation tests to run with start_time set to 0.0 and 15.0.

Reviewed changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated 1 comment.

File	Description
experanto/interpolators.py	Corrects linear interpolation time math to account for non-zero start_time (and phase shifts for the phase-shifted interpolator).
tests/test_sequence_interpolator.py	Adds coverage for start_time != 0 in linear interpolation tests.
diff_output.txt	Newly added artifact file containing an encoded diff; appears unintended.

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[binary69]

hey @pollytur @schewskone did the changes, happy to get a review :)

[Copilot]

Pull request overview

Fixes linear interpolation correctness when start_time != 0 for sequence-based interpolators, aligning computed sample times with the underlying timestamp origin (and per-signal phase shifts).

Changes:

• Correct SequenceInterpolator.interpolate(..., interpolation_mode="linear") to include start_time in times_lower/times_upper.
• Correct PhaseShiftedSequenceInterpolator.interpolate(..., interpolation_mode="linear") to include start_time (and phase shifts) in times_lower/times_upper, and apply the overflow row mask consistently to all derived arrays.
• Extend linear interpolation tests to cover non-zero start_time.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
experanto/interpolators.py	Fixes linear interpolation time math for non-zero start_time (and phase-shifted linear path), ensuring correct weight computation and consistent masking.
tests/test_sequence_interpolator.py	Expands linear interpolation test parametrization to validate behavior when start_time is non-zero.

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[schewskone]

LGTM, thanks for fixing this.