v0.8.0

What’s Changed

• Nonlinear (elasto-plastic) beam analysis (NonlinearBeamAnalysis) — #140
• Non-prismatic (variable-EI) elements (SectionEI) — #139
• Imposed-curvature (initial-strain) loads (add_ic, load type 6) — #139
• plus Markdown (MyST) documentation migration

Verification

• Full suite: 117 passed (incl. the new test_rejects_nonprismatic_member).
• Docs build warning-free; the prismatic-only note renders correctly in the nonlinear tutorial.

v0.7.0

v0.7.0

Features

Trapezoidal (linearly varying) distributed load (#101)

New load type 5 supports linearly varying distributed loads. Full-span form [span, 5, w1, w2] applies intensity w1 at the left end varying to w2 at the right. Partial form [span, 5, w1, w2, a, c] applies the load starting at position a over cover length c. A convenience method BeamAnalysis.add_trap() is also provided.

Coincident load effects on envelopes (#122)

When computing envelopes from a moving vehicle analysis, the co-existing value of the other effect (V or M) at the truck position that caused each envelope extreme is now tracked. New Envelopes attributes: Vco_Mmax, Vco_Mmin, Mco_Vmax, Mco_Vmin. The critical_values() output now includes "Vco" and "Mco" keys. Coincident values are preserved through augment() and zero_like().

Envelope addition (#92)

New Envelopes.sum() method for element-wise addition of compatible envelopes, enabling superposition of load effects from different sources (e.g. patterned UDL + moving vehicle envelopes).

Vehicle traverse range control (#53)

New pos_start and pos_end parameters on BridgeAnalysis.run_vehicle() restrict the vehicle traverse to a specified range. Useful for transverse deck analyses where the vehicle is confined to specific lanes.

Bug Fixes

Influence line IndexError (#89)

Fixed InfluenceLines.get_il() raising IndexError when the point of interest does not fall exactly on the result grid. Root cause was overly tight floating-point tolerance and zero-valued padding indices at span boundaries.

What’s Changed

• Format Python code with psf/black push (#129) @github-actions[bot]
• Add coincident load effects to Envelopes (#128) @ccaprani
• Add trapezoidal (linearly varying) distributed load type (#127) @ccaprani
• Add pos_start/pos_end to BridgeAnalysis.run_vehicle() (#126) @ccaprani
• Add Envelopes.sum() for element-wise envelope addition (#125) @ccaprani
• Fix InfluenceLines.get_il() IndexError for arbitrary poi values (#124) @ccaprani

v0.6.0

v0.6.0 — Release Notes

New Features

• Prescribed displacements: Support for imposing known displacements at any DOF, enabling modelling of support settlements. Specify via the D argument to BeamAnalysis.
• Spring support reactions: Spring forces are now reported in beam_results.Rs (upward positive, i.e. -k_s × u).

Bug Fixes

• Load superposition: Fixed MemberResults.__add__ which was incorrectly accumulating shear (V) instead of rotation (R) when superimposing load cases.
• Spring stiffness double-counting: Fixed a bug where spring stiffness was being added to the global stiffness matrix twice, giving incorrect results for spring-supported beams.
• Spring reaction sign: Spring forces in beam_results.Rs are now reported with correct sign (upward positive).

Improvements

• Theory documentation: Expanded theory.ipynb to cover global stiffness matrix assembly, spring supports, boundary condition enforcement, prescribed displacements, and reaction recovery.
• Type definitions: Shared types (LoadType, LoadMatrix, LoadCNL, MemberResults) consolidated into types.py; explicit API exports replace wildcard imports.
• CI: Dropped Python 3.8 support; added Python 3.12 and 3.13 to the test matrix. Minimum supported version is now Python 3.9.
• Docs build: Replaced the unmaintained ammaraskar/sphinx-action with a native build step, fixing the GitHub Pages deployment.

Full Changelog: v0.5.2...v0.6.0

v0.5.2

What's Changed

• Added some theory docs by @ccaprani in #83
• Minor fix for plot envelopes by @RoccoRaimo in #90
• Upgrade scipy to cumulative_trapezoidal by @ccaprani in #100

New Contributors

• @RoccoRaimo made their first contribution in #90

Full Changelog: v0.5.1...v0.5.2

v0.5.1

What's Changed

• Added some theory docs by @ccaprani in #83
• Fix deflections for etype 3 and 4 by @ccaprani in #80
• Format Python code with psf/black push by @github-actions in #78

v0.5

What’s Changed

• Deflection shape fixes for all element types (#77) @ccaprani
• corrected released end forces for etype=3 (Pinned-Fixed) (#75) @tpanagiotakos
• Format Python code with psf/black push (#74) @github-actions
• Bump codecov/codecov-action from 4.1.0 to 4.1.1 (#76) @dependabot

v0.4.2

What’s Changed

• Fix for returning IL of vertical support near the POI (#73) @ccaprani

v0.4.1

What’s Changed

• CS454 Additions (#68) @ccaprani
• Added and example to Envelopes notebook (#55) @AlexGriffiths526
• Add example to Envelopes (#57) @ccaprani
• Format Python code with psf/black push (#52) @github-actions

v0.4.0

What’s Changed

• Added new automatic load patterning for continuous beams
• Added plot of load patterning envelopes
• Added new examples notebook on load patterning & envelopes
• Added test for enveloping.
• Corrected that BMDs are plotted positive below the axis [per #48]

PRs:

• Envelopes (#51) @ccaprani
• Correct BMD signs per #48 (#49) @ccaprani

v0.3

What’s Changed

Features

• AS5100.2 Appendix C example (#47) @ccaprani
• Added functionality to have static loads as well as moving vehicle loads in a BridgeAnalysis (#47).
• Renamed the from_convoy to make_train and moved outside Vehicle class (#47).
• Updated make_train example accordingly (#47).
• Added utility functions for loads (#38) @ccaprani

Bug Fixes

• Fix the wrong IL for 7-related spans (#40) @CaiZhou2
• Fix heading levels error in docs (#39) @ccaprani
• Docs (#34) @ccaprani