Fixed

• Fixed State::critical_point_binary at fixed pressure, which evaluated the pressure at the wrong volume and never converged. #402
• Fixed PhaseEquilibrium::tp_flash with an initial state returning the previous phase split if only the feed composition changes. #402
• Fixed implicit derivatives in State::new_nph, new_nps, new_nth, new_nts, and new_nvu being lost if the initial guess is already converged.
• Fixed State::residual_chemical_potential_contributions passing the temperature as molar volume. #402
• Fixed duplicate point in PhaseDiagram::dew_point_line. #402

Fixed

• Fixed bug in _density_iteration which used the residual Helmholtz energy as the pressure and the pressure as derivative. #396
• Fixed missing mole fraction factor in State::thermodynamic_factor. #400
• Fixed State::henrys_law_constant for mixed solvents. #400
• Fixed the acceleration in PhaseEquilibrium::tp_flash (Gibbs energy acceptance criterion not weighted by phase fractions and incomplete K-value history). #400

Fixed

• Fixed numerical roundoff errors in the analytic solution of association site fractions for asymmetric association schemes. #393,#394

Fixed

• Fixed off-by-one error for the convergence-check in _density_iteration. #386
• Fixed erroneously transposed jacobian layout in binary association of PcSaftBinary. #386
• Fixed parsing of binary group/group interaction parameters in gc-PC-SAFT. #389
• Fixed analytic solution of association site fractions for mixture DFT. #391

Fixed

• Fixed some unwraps in VLE routines. #367

Packaging

• Updated github action workflows to include pyodide/emscripten wheels. #368

Added

• Extended tp-flash algorithm to static numbers of components and enabled automatic differentiation for binary systems. #336
• Rewrote PhaseEquilibrium::pure_p to mirror pure_t and enabled automatic differentiation. #337
• Added boiling_temperature to the list of properties for parallel evaluations of gradients. #337
• Added the Composition trait to allow more flexibility in the creation of states and phase equilibria. #330
• Added PhaseEquilibrium::ph_flash and PhaseEquilibrium::ps_flash. #338
• Added getters for vapor_phase_fraction, molar_enthalpy, molar_entropy, total_moles, enthalpy, and entropy to PhaseEquilibrium. #338
• Added PropertyAD trait in feos_core::ad with one struct per property for uniform evaluation with or without parameter derivatives, including parallel variants. #358
• Added feos_core::ad::dataset module with PureDataset and BinaryDataset types, constructible from records, CSV files, or readers, for use in parameter fits. #358
• Exposed Property, PureDataset, and BinaryDataset in py-feos. #358
• Implemented IdealGasAD<D> for Dippr. #357
• Added PhaseEquilibrium::binary_azeotrope that quickly finds azeotropes in binary mixtures for a given temperature or pressure. #365

Changed

• Removed any assumptions about the total number of moles in a State or PhaseEquilibrium. Evaluating extensive properties now returns a Result. #330
• Redesigned the IdealGas trait and added IdealGasAD in analogy to ResidualDyn and Residual. #330
• Replaced the PropertiesAD blanket-impl trait with per-property PropertyAD types. #358
• Replaced ParametersAD::named_derivatives with a build constructor and seed_derivatives(&values, names). #358
• Removed the per-property *_derivatives free functions in Python in favour of static methods on the new Property class. #358

Removed

• Removed the StateBuilder struct, because it is mostly obsolete with the addition of the Composition trait. #330

Packaging

• Updated quantity dependency to 0.13 and removed the typenum dependency. #328
• Added csv as a feos-core dependency for the new dataset module. #358
• Updated pyo3, pythonize and numpy dependencies to 0.29. #360
• Updated quantity and num-dual dependencies to 0.14. #360
• Updated nalgebra dependency to 0.35. #360
• Updated gauss-quad dependency to 0.3. #360
• Update itertools dependency to 0.15.

Fixed

• Fixed PhaseDiagram.binary_vle() panicking during search for VLLE (tried to access unallocated element). #362
• Fixed reading binary association parameters from JSON. #363

Added

• Add Rayon global thread pool control via FEOS_MAX_THREADS and set_num_threads()/ get_num_threads() to Python. #346
• Added DIPPR107 parameterization for ideal gas heat capacities of Burkhardt et al. #344

Fixed

• Fixed the calculation of temperature and pressure derivatives of dew and bubble points. #347
• Fixed the implementation of binary interaction parameters in ePC-SAFT. #353

Changed

• Automatically detect VLLEs in BinaryPhaseDiagram. #341

Fixed

• Fixed the sign of the isothermal compressibility. #342

Thanks @RolfStierle for the contribution!

Added

• Added py-feos tests to GitHub Actions and moved pyo3/extension-module feature to pyproject.toml. #334

Fixed

• Fixed None transformation when binary parameters are provided to PyParameters to properly raise errors. #334
• Fixed the calculation of critical points and tp-flashes when one or more of the mixture components have zero composition. #331