Pywr

New Features

- Performance improvements for the GLPK solvers. Several new options have been added to the GLPK solvers that
reduce the number of linear programme updates required each time-step. These options are currently off by default,
but can be enabled by either passing keyword arguments to the solver instances or via environment variables.
(912, 983, 985)
- Update constant and fixed flows only once during reset (`PYWR_SOLVER_GLPK_FIXED_FLOWS_ONCE=True`)
- Update constant and fixed costs only once during reset (`PYWR_SOLVER_GLPK_FIXED_COSTS_ONCE=True`)
- Update constant and fixed aggregated node factors only once during reset (`PYWR_SOLVER_GLPK_FIXED_FACTORS_ONCE=True`)
- Improve memory usage in `DataFrameParameter` when running a subset of the defined scenarios. The parameter now only
retains the data for the subset of scenarios required for the simulation instead of all scenarios. (981)
- Update `MonthlyProfileParameter` and `RbfProfileParameter` to allow variable lower and upper bounds to be defined. (986)

Bug Fixes

- Fix use of deprecated `np.int` and `np.float` types. (982)

New Features

- Allow target flow-duration curves to be supplied in an external file for `FlowDurationDeviationRecorder`. (977)
- Allow only one of upper or lower targets to be specified in `FlowDurationDeviationRecorder`. (977)

Bug Fixes

- Fix bug where event recorders were not registered and could not be loaded from JSON. (976)

Bug Fixes

- Allow loading normalised KDE and `NumpyArrayNormalisedStorageRecorder` recorder from JSON. (974)

New Features

- Added `LossLink` node. (960)
- Added `MultiThresholdIndexParameter`. (969)
- Added two recorders that fit a KDE to time-series of storage volumes. (970, 971)
- Added an optional tags dictionary to `Component` for storing user defined metadata. (968)

Bug Fixes

- Support loading "area" and "level" attributes as parameters correctly. (972)

Miscellaneous

- Added CI support for Python-3.9 on manylinux. (954)

New Features

- Add additional "activation function" parameters: `BinaryStepParameter`, `RectifierParameter` and `LogisticParameter`. (965)

New Features

- Refactor node loading into two stages to solve circular loading problems. (945)
- Add additional `get_all_xxx` methods to core nodes to allow fetching `min_flow`, `max_flow` and `cost`
values for all scenarios simultaneously. (958)

Miscellaneous

- Switch to using Openpyxl for reading and writing Excel files (see changes to Pandas v1.2). (959)
- Dropped support for Python 3.6 following lack of support in upstream libraries (NumPy and Pandas). (959)