Changelog¶

This page summarizes user-facing changes per release. GitHub Releases (linked at the top of each section) contain the full commit log.

v0.2.0 — Interactive layer + Tier-1 adoption polish¶

Published: May 2026 · PyPI · GitHub tag

Major release. Turned the engine into something you can play with in a browser.

5-page Streamlit app (pitchphys-app console script): Pitch Playground, Magnus Explorer, Fastball-vs-Curveball, Active-Spin/Gyro, Drag+Environment.
3D Plotly visualization: trajectory_3d, compare_pitches_3d, add_spin_axis_arrow, add_force_vectors.
Animated ball flight: animate_pitch and animate_pitches with play/pause/scrub via Plotly frames.
3 tutorial notebooks under notebooks/, Colab-runnable: 03_magnus_effect_fastball_curveball.ipynb, 05_active_spin_vs_gyro_spin.ipynb, 09_build_your_own_pitch.ipynb. Each auto-installs pitchphys on Colab.
Streamlit Cloud configs (.streamlit/config.toml, requirements.txt, runtime.txt) for one-click deployment.
Strike-zone "is it a strike?" indicator on every relevant page.
URL state encoding — every Pitch Playground slider is captured in the URL, so you can share a link to any pitch you build.
Cross-page pitch persistence via st.session_state["canonical_pitch"].
Download buttons for trajectory CSV, break-metrics JSON, and 3D-figure HTML.
Statcast comparison form on the Pitch Playground: observed/simulated/Δ columns for release speed, spin rate, tilt, IVB, horizontal break.
GitHub Actions for CI tests, docs deploy, PyPI publish (OIDC trusted publishing), and Streamlit Cloud keepalive cron.
PyPI publishing: pip install pitchphys now works.

pyproject.toml now declares [viz], [app], [dev], [docs] optional-dependency groups.
Console script pitchphys-app resolves the bundled app/streamlit_app.py via importlib.resources with a source-checkout fallback.

174 → 185 tests passing. New: tests/test_plot3d.py, tests/test_animation.py, tests/test_app_utils.py, tests/test_app_launcher.py, tests/test_app_extras.py.

Published: May 2026 (commit d8846c6 on main).

The physics core got calibrated against published wind-tunnel and motion-capture data.

LyuAeroModel — drag-crisis Cd(Re, S) and seam-averaged Cl(S) from Lyu, Smith, Elliott & Kensrud (2022). Now the default for model="magnus".
Spin decay — omega(t) = omega_0 · exp(-t/τ) with default τ = 1.5 s. Pass spin_decay_tau_s=None to disable.
Environment.from_weather(temp_c, pressure_pa, humidity) — ideal gas + Tetens humidity correction + Sutherland viscosity.
Regression test against Nathan 2008 Table I — 4-pitch deflection sanity check pins the model to published numbers.

NathanLiftModel rewritten to use the Sawicki–Hubbard–Stronge (2003) bilinear Cl(S) that Nathan 2008 actually validated. The previous misattributed rational fit was removed (v0.1 had it credited to Nathan; the actual paper does not propose that formula).

Published: May 2026 (commit d8846c6 as "Initial commit").

The first usable version. Core engine + 2D matplotlib viz + 5 pedagogical pitch presets.

Core simulator: gravity, drag, Magnus (simple linear-in-S model), composable force toggles, scipy solve_ivp integrator with plate-crossing event termination.
Data models: Baseball, Environment, PitchRelease, TrajectoryResult.
Pluggable AeroModel Protocol with SimpleMagnusModel, NathanLiftModel (initial rational form), ConstantAeroModel, UserDefinedAeroModel.
Pitch presets: four_seam, curveball, slider, sinker, changeup.
2D Matplotlib helpers: side_view, catcher_view, top_view, compare_pitches.
Break metrics in baseball-friendly units (mph, ft, in) over an SI engine.
110 tests with analytic-projectile and qualitative-behavior regressions.
Clock-tilt spin-axis convention pinned in pitchphys.coordinates.
MIT license, Python ≥3.11, ruff + mypy clean.