CHANGELOG.md

Changelog

All notable changes to this project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

Unreleased

Changed

• the instances of data/ are downloaded and extracted by the targets download_investment_<fmt> and extract_investment_<fmt>, written as in every module that keeps its instances in the Package Registry, and the marker of the extraction carries the format in its name, so that a tree extracted before extracts once more

0.3.0 - 2026-10-09

Added

• the asset type 2 (AssetType), the converter of a BatteryUnitBlock, whose investment is the kappa of the converter (BatteryUnitBlock::set_converter_kappa()) with its own cost, bounds and linearization: with an asset of type 0 on the same battery the storage and the converter are sized apart, while a battery with no asset of type 2 is resized as a whole by its kappa, as before

• the key UnitBlockSolverConfig of the extra Configuration of InvestmentFunction, the BlockSolverConfig of the copy of a scaled unit with no copies that the linearization solves; if absent, with a UCBlock as inner Block its BlockSolverConfig is used

• test/, the unit test of the module (InvestmentBlock_unit_test): the curvature InvestmentFunction declares, and, with a :MILPSolver in the build, its linearization against the finite differences of its value for a line of a meshed network and for a scaled unit giving reactive power

• the netCDF variable Integer, scalar or per asset, which makes the ColVariable of the assets where it is nonzero integer, e.g., the number of modules of a modular asset; a BundleSolver with intIntVars 1 keeps them integer

• the data archive 2026-09-26, which adds to pypsa-data one scenario of the modular family of pypsa2smspp with the design in an InvestmentBlock over the UCBlock (smspp_mod_t48_s1_b2c_det_investment.nc), the same network the archive of UCBlock has with the design in the units

Changed

• InvestmentFunction throws when the asset is a line that has a design variable in the DCNetworkBlock, whose kappa multiplies that variable, instead of giving it a zero linearization; the documentation states the convexity of a battery in its kappa through the continuous relaxation

• the class comments of InvestmentFunction.h write the function (cost of the investment plus operational cost), how each asset enters the inner Block, the linearization and when it is a subgradient, its convexity and domain, and what a capacity expansion model may have that it has not (a worst case over models of the uncertainty, for which they give the formulation with one InvestmentFunction per model); the doc says the defaults the code has, InstalledQuantity 0 and no bounds on the ColVariable of the InvestmentBlock, and all its formulae are in LaTeX

• the data archive is downloaded by version: DATA_VERSION in CMakeLists.txt names the version of the Package Registry to read, and the archive and the marker of its extraction carry it in their name, so that a tree holding an older extraction (the cache of the CI, or a clone extracted before) downloads and extracts again instead of running on the old data; data/upload-nc4 publishes the archive under that version

• InvestmentFunction::compute() says which Solver of the inner Block returned which status when that Solver gives no solution and no proof that there is none: the caller reads kError and nothing else, so a run that stopped there told neither what answered nor what it answered

• the comment of the feasibility cut says why a certificate of infeasibility supports no cut against a scaled design, a kappa entering the constraints it appears in through their right-hand side alone, with the numbers of the instance where it was measured

• the two indices of a unit under investment are named inside the loop and not by a structured binding of it, a structured binding being what a lambda cannot capture when OpenMP is on

• the walk over what a Block holds asks the Block for its groups of Constraint, one run at a time, rather than the vectors of boost::any that are not there any more: the constant of a cut is summed over them, and a combination of linearizations keeps the coefficients of its constituents whatever their number

• whoever links the module keeps it: the classes of a module register themselves in the factory from a static initialiser, and a linker that drops what looks unused takes the registration away with it, so the target now tells whoever links it to keep the symbol that forces the module in, and on ELF, where naming the symbol is not enough, the library as a whole

Fixed

• the linearization of a unit represented by its scale factor with no copies: the operational part of the coefficient was read from the solution of the unit, in which it weighs nothing, and was 0 (the unit being off) also where building it pays, so that a method starting at 0 copies stopped there; it is the value at the dual values of a copy of the unit solved alone, relaxed as in the inner Block, by the Solver of UnitBlockSolverConfig, which is a subgradient

• the linearization with respect to a line no longer asserts that the network is HVDC, which aborted builds with assertions on any network with susceptances, the derivative of the flow limits being the same there

• the linearization with respect to a unit represented by its scale counts the reactive node injection constraints, which also carry the scaled reactive power of the unit and were left out

• is_convex() and is_concave() look at the inner Block, which has to be there and minimize (maximize), and at the cost of investing plus that of disinvesting in each asset, c + d, which has to be nonnegative (nonpositive) for the investment cost to be convex (concave); they returned true and false whatever the InvestmentFunction

• on macOS a program linking the module lost the classes the module registers in the factories when the linker dropped the library, as it does under -dead_strip_dylibs, which conda sets: the target now asks the linker for the symbol that forces the module in (-u), which ld64, unlike the ELF linker, counts as a use of the library

• with more than one MPI process, every process of an InvestmentFunction over an SDDPBlock gets the value and the linearization that process 0 simulates: the others used to come back with neither, so that their Solver stopped at the first point and left process 0 waiting in the next training

• the derivative with respect to the scale factor of a unit takes in the rows of the pollutant budget, the storage levels of the unit included

• after a compute that fails, the Function hears again the Modification of its inner Block

• the derivative with respect to the scale factor of a unit subtracts its fixed consumption when it is off

• the step that fetches the data archive of this module says what went wrong when it goes wrong: the download is checked, an archive that did not arrive is removed instead of being left on disk for the build to take for the real one, and the message names the URL. A server that answers with an error page used to leave a file of a few bytes there, which made the next build fail while extracting it, with the message of tar and no mention of the download

• makefile-c takes TwoStageStochasticBlock from its makefile-s, so that the core SMS++ objects are not listed twice

0.2.0 - 2026-09-12

Added

• the inner Block of an InvestmentFunction can be a TwoStageStochasticBlock, whose here-and-now Variable then live outside the scenarios in a single copy: the investment is written into every leaf of the scenario structure, and the linearization is read from every sub-Block that carries it

• the value function has a vertical linearization where the inner Block is infeasible, i.e., the feasibility cut of a Benders decomposition, and a provably infeasible inner subproblem is reported as kInfeasible rather than kError

Changed

• the linearization in the capacity of a unit is asked to UnitBlock::get_kappa_linearization()

• the accessor to the inner Block is gone, get_nested_Blocks() being it

• the version of the module is the git tag of its repository, or the VERSION.txt of a release tarball, and the shared library carries it: its SONAME is major.minor while the major is 0, and it is installed with an RPATH relative to itself, so that an installed tree keeps working wherever it is moved

Fixed

• the derivative of a flow limit carries the factor the limit is scaled by

• each replica of the inner Block of an InvestmentFunction is un-configured with the clone that configured it

• the package configuration file finds the libraries the module links, so that a project using the installed module needs nothing more than find_package(), StOpt comprised

0.1.1 - 2025-12-12

Added

• added Configuration for output Solution

• integration of test/ with common_utils (although test/ will have to be removed)

• InvestmentBlockSolution and its handling

Changed

• adapted to new standard organization of makefiles

Fixed

• properly translated investment variable values in InvestmentBlockSolution when f_reformulate_bounds == true

0.1.0 - 2024-02-29

Added

• First test release