DESDEO 2.5.0

[2.5.0] - 9.6.2026

Core logic

Added

• Added scenario-based optimization support: a new ScenarioModel/Scenario
  model (desdeo/problem/scenario.py) that references pooled
  constants/variables/constraints/objectives by index, and tools in
  desdeo/tools/scenarios.py for constructing and solving scenario problems
  (build_scenario_problem, build_combined_scenario_problem,
  solve_scenario, solve_all_scenarios) (#472).
• Added stochastic optimization tools (desdeo/tools/stochastic.py):
  add_expected_asf, add_expected_value, and add_weighted_scenarios for
  aggregating objectives over probability-weighted scenarios (#472).
• Added worst-case robust optimization (desdeo/tools/robust.py):
  add_worst_case_robust, using the standard epigraph reformulation over a
  combined scenario problem (#472).
• Added partial scalarization (desdeo/tools/partial_scalarization.py):
  add_asf_partial_diff, a differentiable ASF that scalarizes only the subset
  of objectives present in the reference point (#472).
• Added a summer cabin electricity test problem family
  (summer_cabin_electricity.py): summer_cabin_battery_problem,
  summer_cabin_battery_problem_split,
  summer_cabin_battery_problem_split_scenario, plus
  generate_solar_profile and generate_summer_cabin_electricity_data
  helpers (#472).
• Added native polars vector operations to the math parser: matrix/array
  random access (extract/exclude with 1-based and end-relative indices),
  matmul, summation, and unary UDFs, with a new
  tests/test_json_parser_vectors.py suite (#472).
• Added matrix random access to gurobipy expression parsing (#472).

Changed

• Refactored scenario handling: replaced the legacy
  scenario_keys/get_scenario_problem mechanism in schema.py with the new
  ScenarioModel, which adds per-scenario probabilities and anticipation info
  for scenario variables (#472).
• Changed evaluator ordering so scalarization functions are evaluated before
  constraints, allowing scalarization symbols to be used inside constraints
  (useful when aggregating over multiple scenarios) (#472).
• Updated the math parser and evaluators to support polars >= 1.41: native
  polars arithmetic for +, -, *, /; pow via a unary UDF for constant
  exponents; matmul/extract/exclude/summation/unary via map_batches;
  reshape-based tensor unflattening; and a _safe_hstack that tolerates an
  empty frame in the simulator evaluator.
• Updated SCORE Bands visualization (desdeo/tools/score_bands.py):
  scaling now based on score_json instead of the raw data, added axis-color
  and cluster-name customization, support for visualizing individual
  solutions, and a new tick value/position calculation.

Removed

• Removed the legacy scenario_keys handling from the problem schema,
  including parse_scenario_key_singleton_to_list and
  Problem.get_scenario_problem, superseded by ScenarioModel (#472).

Fixed

• Fixed type hints and minor issues in interaction_schema.py.
• Fixed the Metallurgical application JSON problem file (MetallAppl.json).

Web GUI

Added

• Added automatic breadcrumbs to the topbar (topbar-breadcrumbs
  component), driven by a path-to-label map and shown across the groups,
  interactive-methods, manage-users, methods, and problems layouts.
• Added a Solution Comparison Table component
  (solution-comparison.svelte) that highlights whether each candidate
  objective value is better than the reference solution.

Documentation

Added

• Added a scenario-based optimization explanation guide
  (docs/explanation/scenarios.md) and a standalone scenarios notebook,
  inlined/fetched to avoid a heavy notebook in the docs build (#476, #477,
  #478).

Changed

• Fixed broken and incorrect links and various typos across the tutorials and
  documentation, and reordered the Explanation navigation (Models/schema,
  Group decision making, Websockets) to match the index order.
• Updated the Discord invite links, which were incorrect.

Tooling, CI, and deployment

Added

• Added an optional stochastic dependency group (mpi-sppy), kept out of
  the default install so the automated tests keep working, at least for now.

Changed

• Bumped dependencies: cvxpy[scip] to >= 1.8.0, < 1.9, pinned numpy
  (>= 2.2.0, < 2.4) and cma for compatibility, and refreshed uv.lock.
• Set the notebook execute option to false in mkdocs.rtd.yml, moved the
  scenarios notebook out of the docs build, cleaned notebook outputs, and
  updated pre-commit.

Rumor has it (automatically generated)

• Breadcrumbs by @MajoMartinco in #463
• Solution Comparison Table component added by @MajoMartinco in #470
• Stochastic optimization stuff by @juropo in #472
• Update the scenario example and cvxpy version by @juropo in #476
• Get scenarios.ipynb from github instead of building it by @juropo in #477
• Inline the scenario example to get rid of heavy notebook by @juropo in #478
• Updating Discord invites and improving grammar by @Mastereeli in #488
• fixed a typo by @lukarantalainen in #494
• added typing by @lukarantalainen in #495
• fixed typing by @lukarantalainen in #497
• fixed a few links and typos by @lukarantalainen in #506
• Fixed links in the "Explanation" section of the documentation by @Mastereeli in #507
• Fixing links by @Ukez1 in #498
• Fixing some typos in DESDEO/docs/home/about.md by @Ukez1 in #496
• Added tests for river pollution and binh and korn problems. by @Mastereeli in #509

New Contributors

• @lukarantalainen made their first contribution in #494
• @Ukez1 made their first contribution in #498

Full Changelog: v2.4.0...v2.5.0