cosapp

Name	cosapp JSON
Version	0.16.0 JSON
	download
home_page	https://cosapp.readthedocs.io
Summary	CoSApp, the Collaborative System Approach.
upload_time	2024-04-18 14:27:45
maintainer	None
docs_url	None
author	CoSApp Development Team
requires_python	>=3.8
license	Apache-2.0
keywords	cosapp system simulation system design
VCS
bugtrack_url
requirements	No requirements were recorded.
Travis-CI	No Travis.
coveralls test coverage	No coveralls.

            # CoSApp - Collaborative System Approach

The primary goal of **CoSApp** is to help technical departments in the design of complex systems.
To do so, the framework allows the simulation of various systems representing the different parts of the final product in a common environment.
The benefit is the ability for each subsystem team to carry out design study with a direct feedback at product level.

The main features are:

### Butterfly effect

Couple your simulation models with CoSApp to get immediate impact on main product variables and iterate to converge on a better design.

### Design guidance

All systems can share design parameters associated with an acceptable range.
You can take advantage of those limited degrees of freedom without fear of breaking your collaborators' work.

### Flexible simulation workflows

CoSApp solvers can be combined into versatile, customized workflows that fit specific simulation intents.

Have a look at the [introduction](https://cosapp.readthedocs.io/en/stable/tutorials/00-Introduction.html#), containing many tutorials!

This code is the property of Safran SA.
It uses code coming from various open-source projects (see [LICENSE](https://gitlab.com/cosapp/cosapp/blob/master/LICENSE.rst) file).

# Citing

If you use CoSApp, please cite us!

Lac *et al.* (2024), [CoSApp: a Python library to create, simulate and design complex systems](https://doi.org/10.21105/joss.06292), Journal of Open Source Software 9(94), 6292. 

BibTeX entry:

```bibtex
@article{Lac.etal:joss2024, author={Étienne Lac and Guy {De Spiegeleer} and Adrien Delsalle and Frédéric Collonval and Duc-Trung Lê and Mathias Malandain}, title={CoSApp: a Python library to create, simulate and design complex systems}, journal={Journal of Open Source Software}, year={2024}, volume={9}, number={94}, pages={6292}, doi={10.21105/joss.06292}, publisher={The Open Journal}}
```

# Try it now!

Run a Jupyter Lab instance with binder to try out CoSApp features through examples.

[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gl/cosapp%2Fcosapp/master?urlpath=lab/tree/docs/tutorials)

# History


## 0.16.0 (2024-04-18)

### Bug fixes and code quality

- Primary events triggered within the same time step are now correctly captured (MR [#287](https://gitlab.com/cosapp/cosapp/-/merge_requests/287)).
  A bug persists when several primary events occur at the exact same time, though, as only one will be retained.
- Fix bug preventing events from occurring during the first time step of a simulation (MR [#288](https://gitlab.com/cosapp/cosapp/-/merge_requests/288)).
- Fix a bug causing recorders to crash when inspecting ports with properties (MR [#282](https://gitlab.com/cosapp/cosapp/-/merge_requests/282)).
- Algebraic and time-dependent problems are now dissociated (MR [#284](https://gitlab.com/cosapp/cosapp/-/merge_requests/284)). As a consequence, invoking `self.problem.clear()` during transitions, for instance, no longer affects time-dependent unknowns such as transients.
- Fix ambiguous warning message raised by `RunSingleCase` (MR [#279](https://gitlab.com/cosapp/cosapp/-/merge_requests/279)).
- Various refactoring passes (MRs [#283](https://gitlab.com/cosapp/cosapp/-/merge_requests/283) and [#286](https://gitlab.com/cosapp/cosapp/-/merge_requests/286)).

### Maintenance

- Updated description inside the conda recipe (MR [#276](https://gitlab.com/cosapp/cosapp/-/merge_requests/276)).
- Pin `pytest` version due to a bug in version 8.1 (MR [#280](https://gitlab.com/cosapp/cosapp/-/merge_requests/280)).
- Add a "Citing" section in the main README file (MR [#281](https://gitlab.com/cosapp/cosapp/-/merge_requests/281)).
- The module parser was updated (MR [#285](https://gitlab.com/cosapp/cosapp/-/merge_requests/285)).
- Force `sphinx` < 7.3 in the documentation building environment, owing to an incompatibility with `sphinx-mdinclude` (MR [#289](https://gitlab.com/cosapp/cosapp/-/merge_requests/289)). This is a temporary patch until root cause is fixed.


## 0.15.4 (2024-02-28)

### Bug fixes and code quality

- Fix bug raised in `NonLinearSolver` for systems with rates (MR [#268](https://gitlab.com/cosapp/cosapp/-/merge_requests/268)).
- Minor refactoring pass (MR [#274](https://gitlab.com/cosapp/cosapp/-/merge_requests/274)).

### Maintenance

- Drop Python 3.8 support and add Python 3.11 test pipeline (MR [#270](https://gitlab.com/cosapp/cosapp/-/merge_requests/270)).
- Update installation and contribution guidelines (MR [#270](https://gitlab.com/cosapp/cosapp/-/merge_requests/270)).
- Update dependency list (MRs [#269](https://gitlab.com/cosapp/cosapp/-/merge_requests/269) and [#270](https://gitlab.com/cosapp/cosapp/-/merge_requests/270)).

### JOSS article

Publication of an article on CoSApp in the [Journal of Open-Source Software](https://joss.theoj.org/), referenced to version 0.15.4 (MR [#271](https://gitlab.com/cosapp/cosapp/-/merge_requests/271)).


## 0.15.3 (2023-12-19)

### Bug fixes and code quality

- Fix minor bug in `NonLinearSolver` (MR [#261](https://gitlab.com/cosapp/cosapp/-/merge_requests/261)).
- Fix incorrect return type hints in `System` (MR [#259](https://gitlab.com/cosapp/cosapp/-/merge_requests/259)).
- Improve support for read-only properties in system getters and setters (MR [#264](https://gitlab.com/cosapp/cosapp/-/merge_requests/264)).

### Maintenance

- Remove deprecated dependency for compatibility with Python 3.12 (MR [#258](https://gitlab.com/cosapp/cosapp/-/merge_requests/258)).
- Force `pythonfmu` < 0.6.3 in dependency list, to prevent a crash during tests (MR [#262](https://gitlab.com/cosapp/cosapp/-/merge_requests/262)). Temporary fix until root cause is identified.


## 0.15.2 (2023-10-14)

### Bug fixes

- Fix crash with `VisJs` rendering of sub-systems (MR [#252](https://gitlab.com/cosapp/cosapp/-/merge_requests/252)).
- Fix minor bug in `EvalString` (MR [#253](https://gitlab.com/cosapp/cosapp/-/merge_requests/253)).
- Fix bad synchronization of mode variables during transitions (MR [#254](https://gitlab.com/cosapp/cosapp/-/merge_requests/254)).
- Improve error message when pulling variables with different roles (MR [#255](https://gitlab.com/cosapp/cosapp/-/merge_requests/255)).
- Fix `TypeError` when passing `pulling` argument as a tuple in `System.add_child` (MR [#256](https://gitlab.com/cosapp/cosapp/-/merge_requests/256)).


## 0.15.1 (2023-09-18)

### New features & API changes

- The representation of `MathematicalProblem` objects now indicates the number of unknowns and equations, for a better readability (MR [#249](https://gitlab.com/cosapp/cosapp/-/merge_requests/249)).
- Optional argument `execution_index` in `System.add_child` and `Driver.add_child` can now take a negative value, with a behaviour following that of `list.insert` (MR [#250](https://gitlab.com/cosapp/cosapp/-/merge_requests/250)).

### Bug fixes and code quality

- Add missing field "time" in `ExplicitTimeRecorder.event_data`, when no recorder is set (MR [#245](https://gitlab.com/cosapp/cosapp/-/merge_requests/245)).
- Fix bug with recorders inspecting systems with iterators (MRs [#246](https://gitlab.com/cosapp/cosapp/-/merge_requests/246) and [#247](https://gitlab.com/cosapp/cosapp/-/merge_requests/247)).
- Fix bug with `NonLinearSolver` with NumPy array residues (MR [#248](https://gitlab.com/cosapp/cosapp/-/merge_requests/248)).
- Fix initialization bug of targets involving expressions (MR [#249](https://gitlab.com/cosapp/cosapp/-/merge_requests/249)).


## 0.15.0 (2023-07-20)

### New features & API changes

- Suppression of default `RunSingleCase` subdriver `runner` in `NonLinearSolver` drivers (MR [#239](https://gitlab.com/cosapp/cosapp/-/merge_requests/239)).
- Enable target initialization in multi-point design problems (MR [#233](https://gitlab.com/cosapp/cosapp/-/merge_requests/233)).
- New utility function `swap_system` to replace on the fly a subsystem by another `System` instance (MR [#238](https://gitlab.com/cosapp/cosapp/-/merge_requests/238)).

### Bug fixes and code quality

- Refactor driver `Optimizer` (MR [#240](https://gitlab.com/cosapp/cosapp/-/merge_requests/240)).
- Various bug fixes (MRs [#234](https://gitlab.com/cosapp/cosapp/-/merge_requests/234), [#235](https://gitlab.com/cosapp/cosapp/-/merge_requests/235), [#241](https://gitlab.com/cosapp/cosapp/-/merge_requests/241)).

### Documentation

- New tutorial on `swap_system` (MR [#243](https://gitlab.com/cosapp/cosapp/-/merge_requests/243)).
- General update of tutorials (MRs [#232](https://gitlab.com/cosapp/cosapp/-/merge_requests/232) and [#242](https://gitlab.com/cosapp/cosapp/-/merge_requests/242)).


## 0.14.1 (2023-06-08)

### Bug fixes and code quality

- Fix incorrect output file name in `cosapp.tools.parse_module` (MR [#229](https://gitlab.com/cosapp/cosapp/-/merge_requests/229)).
- Refactoring pass (MR [#230](https://gitlab.com/cosapp/cosapp/-/merge_requests/230)).

### Documentation

- Upgrade documentation build stack (MRs [#224](https://gitlab.com/cosapp/cosapp/-/merge_requests/224) and [#226](https://gitlab.com/cosapp/cosapp/-/merge_requests/226)).
- Fix bad rendering of ports and systems (MRs [#227](https://gitlab.com/cosapp/cosapp/-/merge_requests/227) and [#228](https://gitlab.com/cosapp/cosapp/-/merge_requests/228)).


## 0.14.0 (2023-05-17)

### New features & API changes

* Improved performance, through a revised clean/dirty mechanism (MR [#215](https://gitlab.com/cosapp/cosapp/-/merge_requests/215)).
* Possibility to add a contextual description to sub-systems and ports of a system, as well as sub-drivers (MR [#216](https://gitlab.com/cosapp/cosapp/-/merge_requests/216)). This feature is useful for automatic documentation tools, and has been included in the Markdown representation of systems (also used in function `cosapp.tools.display_doc`). Example:
  
  ```python
  from cosapp.base import System
  from my_module import FlowPort
  
  class MySystem(System):
      def setup(self):
          self.add_input(FlowPort, "fl_in1", desc="Primary inlet flow port")
          self.add_input(FlowPort, "fl_in2", desc="Secondary inlet flow port")
  
          self.add_output(FlowPort, "fl_out")
  ```
  
* New hook function `_parse_module_config`, returning pre-defined settings for `cosapp.tools.parse_module` (MR [#218](https://gitlab.com/cosapp/cosapp/-/merge_requests/218)). This allows module maintainers to simply call
  
  ```python
  from cosapp.tools import parse_module
  import my_module
  
  parse_module(my_module)
  ```

  instead of, *e.g.*,

  ```python
  parse_module(
      my_module,
      ctor_config={
          "ComplexSystem1": [
              dict(n=1, foo=0.5),
              dict(n=2, foo=0.1),
          ],
          "ComplexSystem2": [
              dict(xi=0.0, __alias__="ComplexSystem2_a"),
              dict(xi=1.0, __alias__="ComplexSystem2_b"),
          ],
      },
      excludes=["Foo*", "*Bar?"],
  )
  ```

  provided `my_module._parse_module_config()` returns a dictionary specifying the values of `ctor_config`, `excludes`, *etc.*

* Make `SolverResults` a `dataclass`, for easier handling of `NonLinearSolver.results`, *e.g.* (MR [#220](https://gitlab.com/cosapp/cosapp/-/merge_requests/220)).
* Expose attribute `problem` in system setup (MR [#221](https://gitlab.com/cosapp/cosapp/-/merge_requests/221)). Previously, `problem` was only exposed in method `System.transition`.

### Bug fixes and code quality

* Fix bug in `NonLinearSolver` log message (MR [#214](https://gitlab.com/cosapp/cosapp/-/merge_requests/214)).
* Add missing JSON file in PyPI and conda packages, preventing the use of `cosapp.tools.parse_module` (MR [#219](https://gitlab.com/cosapp/cosapp/-/merge_requests/219)).

### Documentation

* Illustrate port and sub-system description in tutorials (MR [#215](https://gitlab.com/cosapp/cosapp/-/merge_requests/215)).


## 0.13.1 (2023-04-03)

### Bug fixes and code quality

* Update test baseline to pass in a Python 3.11 environment (MR [#200](https://gitlab.com/cosapp/cosapp/-/merge_requests/200)).
* Creation of a dummy system factory, mostly for tests (MR [#201](https://gitlab.com/cosapp/cosapp/-/merge_requests/201)).
* Improve clean/dirty mechanism (MR [#202](https://gitlab.com/cosapp/cosapp/-/merge_requests/202)) and fix incorrect clean/dirty status with surrogate models (MR [#205](https://gitlab.com/cosapp/cosapp/-/merge_requests/205)).
* Fix bug in function `cosapp.tools.display_doc` for classes with setup arguments (MR [#208](https://gitlab.com/cosapp/cosapp/-/merge_requests/208)).
* Various code quality improvements (MRs [#211](https://gitlab.com/cosapp/cosapp/-/merge_requests/211), [#212](https://gitlab.com/cosapp/cosapp/-/merge_requests/212)).

### Documentation

Note: extensive use of self-documenting f-strings (introduced in Python 3.8) has made tutorials incompatible with Python 3.7.

* Updated tutorials (MRs [#203](https://gitlab.com/cosapp/cosapp/-/merge_requests/203), [#206](https://gitlab.com/cosapp/cosapp/-/merge_requests/206), [#207](https://gitlab.com/cosapp/cosapp/-/merge_requests/207), [#210](https://gitlab.com/cosapp/cosapp/-/merge_requests/210)).
* The image used in binder is now based on Python 3.10 (MR [#204](https://gitlab.com/cosapp/cosapp/-/merge_requests/204)).

### Module parser

* New function `parse_module` in `cosapp.tools` collecting all system and port classes within a Python module. This parser, generating a JSON file containing the description of all CoSApp symbols, is primarily meant to be used for constructional GUI applications, developed separately (MRs [#192](https://gitlab.com/cosapp/cosapp/-/merge_requests/192) & [#209](https://gitlab.com/cosapp/cosapp/-/merge_requests/209)).


## 0.13.0 (2023-02-09)

### Python 3.10 support

The code is now tested for Python 3.8, 3.9 and 3.10.
Support of Python 3.7 is thus officially dropped, although no version-specific Python code was introduced in this version of CoSApp.

### New features & API changes

* Module `connectors` moved from `cosapp.core` to `cosapp.ports` (MR [#189](https://gitlab.com/cosapp/cosapp/-/merge_requests/189)).
* New "direct" (with no unit conversion) connector classes `PlainConnector`, `CopyConnector` and `DeepCopyConnector`, in `cosapp.ports.connectors` (MR [#188](https://gitlab.com/cosapp/cosapp/-/merge_requests/188)).
* New method `MathematicalProblem.is_empty()`, equivalent to `shape == (0, 0)` (MR [#186](https://gitlab.com/cosapp/cosapp/-/merge_requests/186)).
* Improved VisJs graph rendering, by limiting node size for long system names (MR [#184](https://gitlab.com/cosapp/cosapp/-/merge_requests/184)).
* New utility functions `get_state` and `set_state` in `cosapp.utils`, for quick system data recovery (MR [#193](https://gitlab.com/cosapp/cosapp/-/merge_requests/193)):

  ```python
  from cosapp.utils import get_state, set_state
  
  s = SomeSystem('s')
  # ... many design steps, say
  
  # Save state in local object
  designed = get_state(s)
  
  s.drivers.clear()
  s.add_driver(SomeDriver('driver'))
  
  try:
      s.run_drivers()
  except:
      # Recover previous state
      set_state(s, designed)
  ```

* Functions `radians`, `degrees` and `arctan2`/`atan2` have been added to the scope of `EvalString` objects, and can therefore be used in equations, *e.g.* (MR [#178](https://gitlab.com/cosapp/cosapp/-/merge_requests/178)).
* Recorders can now record constant properties (MR [#181](https://gitlab.com/cosapp/cosapp/-/merge_requests/181)).
* Deprecation of `System.get_unsolved_problem` in favour of new method `assembled_problem` (MR [#174](https://gitlab.com/cosapp/cosapp/-/merge_requests/174)).
* Inner off-design problem of systems is now exposed as attribute `problem`, but only within the `transition` method (MR [#174](https://gitlab.com/cosapp/cosapp/-/merge_requests/174)). This allows users to add or remove off-design constraints during event-driven transitions, while keeping this property inaccessible the rest of the time.

  ```python
  from cosapp.base import System
  from math import sin, cos
  
  class SomeSystem(System):
      def setup(self):
          self.add_inward('x', 0.0)
          self.add_inward('y', 0.0)
          self.add_outward('z', 0.0)
          a = self.add_event('event_a', trigger='x > y')
          b = self.add_event('event_b', trigger='x < y')
      
      def compute(self):
          self.z = cos(self.x) * sin(self.y)
  
      def transition(self):
          offdesign = self.problem
          if self.event_a.present:
              offdesign.clear()
              offdesign.add_equation('z == 0.5').add_unknown('x')
          if self.event_b.present:
              offdesign.clear()
  ```

### Bug fixes and code quality

* Fix serialization bugs for systems with setup parameters (MR [#180](https://gitlab.com/cosapp/cosapp/-/merge_requests/180)) and `None` variables (MR [#172](https://gitlab.com/cosapp/cosapp/-/merge_requests/172)).
* Bug fix on event time calculation involving array transients (MR [#177](https://gitlab.com/cosapp/cosapp/-/merge_requests/177)).
* Bug fix on possible name conflicts in connector storage (MR [#173](https://gitlab.com/cosapp/cosapp/-/merge_requests/173)).
* Fix inconsistent behaviour of `System.add_child` when a `pulling` error is raised (MR [#197](https://gitlab.com/cosapp/cosapp/-/merge_requests/197)).
* Various code quality improvements (MRs [#175](https://gitlab.com/cosapp/cosapp/-/merge_requests/175), [#185](https://gitlab.com/cosapp/cosapp/-/merge_requests/185), [#186](https://gitlab.com/cosapp/cosapp/-/merge_requests/186), [#187](https://gitlab.com/cosapp/cosapp/-/merge_requests/187), [#190](https://gitlab.com/cosapp/cosapp/-/merge_requests/190), [#191](https://gitlab.com/cosapp/cosapp/-/merge_requests/191), [#194](https://gitlab.com/cosapp/cosapp/-/merge_requests/194)).

### Documentation

* Updated time driver tutorial (MR [#182](https://gitlab.com/cosapp/cosapp/-/merge_requests/182)).
* Updated Tips & Tricks (MR [#196](https://gitlab.com/cosapp/cosapp/-/merge_requests/196)).
* Other updates (MRs [#176](https://gitlab.com/cosapp/cosapp/-/merge_requests/176), [#195](https://gitlab.com/cosapp/cosapp/-/merge_requests/195), [#198](https://gitlab.com/cosapp/cosapp/-/merge_requests/198)).

## 0.12.3 (2022-09-21)

### New features & API changes

* Improved user experience:
  * Auto-completion for dynamically added attributes of systems (ports, subsystems, inwards, outwards, events...) and drivers (sub-drivers) (MRs [#164](https://gitlab.com/cosapp/cosapp/-/merge_requests/164) and [#166](https://gitlab.com/cosapp/cosapp/-/merge_requests/166));
  * Improved representation of mathematical problems, in particular for loop equations and multi-point design problems (MRs [#159](https://gitlab.com/cosapp/cosapp/-/merge_requests/159), [#160](https://gitlab.com/cosapp/cosapp/-/merge_requests/160) and [#163](https://gitlab.com/cosapp/cosapp/-/merge_requests/163)).
* New method `System.new_problem` to facilitate the creation of dynamic design methods, *e.g.* (MR [#162](https://gitlab.com/cosapp/cosapp/-/merge_requests/162)).

### Documentation

* Updated tutorials (MRs [#169](https://gitlab.com/cosapp/cosapp/-/merge_requests/169) and [#170](https://gitlab.com/cosapp/cosapp/-/merge_requests/170)).

### Bug fixes and code quality

* Bug fix on unknown dealiasing (MR [#157](https://gitlab.com/cosapp/cosapp/-/merge_requests/157)).
* Bug fix on port variable export (MR [#158](https://gitlab.com/cosapp/cosapp/-/merge_requests/158)).
* Bug fix on system serialization (MR [#161](https://gitlab.com/cosapp/cosapp/-/merge_requests/161)).
* Bug fix on subsystem read-only constants (MR [#167](https://gitlab.com/cosapp/cosapp/-/merge_requests/167)).
* Various code quality improvements (MRs [#154](https://gitlab.com/cosapp/cosapp/-/merge_requests/154), [#155](https://gitlab.com/cosapp/cosapp/-/merge_requests/155), [#162](https://gitlab.com/cosapp/cosapp/-/merge_requests/162), [#168](https://gitlab.com/cosapp/cosapp/-/merge_requests/168)).

## 0.12.2 (2022-05-26)

### New features & API changes

* Automatic tolerance in `NonLinearSolver` (MRs [#148](https://gitlab.com/cosapp/cosapp/-/merge_requests/148) and [#152](https://gitlab.com/cosapp/cosapp/-/merge_requests/152)).
* `Optimizer.set_objective` is deprecated, in favour of `set_minimum` and `set_maximum` (MR [#150](https://gitlab.com/cosapp/cosapp/-/merge_requests/150)).
* Loop residues are no longer normalized (MR [#151](https://gitlab.com/cosapp/cosapp/-/merge_requests/151)).
* Improved type hints for ports, systems and drivers, in functions whose return type depends on arguments, such as `System.add_child`, `add_driver`, *etc.* (MR [#145](https://gitlab.com/cosapp/cosapp/-/merge_requests/145)).

### Documentation

* Updated tutorials (MRs [#144](https://gitlab.com/cosapp/cosapp/-/merge_requests/144), [#147](https://gitlab.com/cosapp/cosapp/-/merge_requests/147) and [#154](https://gitlab.com/cosapp/cosapp/-/merge_requests/154)).

### Bug fixes and code quality

* Fix inconsistent behaviour of recorders (MR [#143](https://gitlab.com/cosapp/cosapp/-/merge_requests/143)).
* Fix bug on event initialization (MR [#146](https://gitlab.com/cosapp/cosapp/-/merge_requests/146)).
* Fix bad markdown formatting of ports occurring in `jupyterlab` 3.4 (MR [#149](https://gitlab.com/cosapp/cosapp/-/merge_requests/149)).
* Fix failed test caused by a regression in `pytest` 7.1 (MR [#142](https://gitlab.com/cosapp/cosapp/-/merge_requests/142)).

## 0.12.1 (2022-02-25)

### New features & API changes

* Simplification of driver `Optimizer`:
  * Suppression of sub-driver `runner` (MR [#136](https://gitlab.com/cosapp/cosapp/-/merge_requests/136)). This change introduces new methods `set_objective`, `add_unknowns` and `add_constraints` in driver `Optimizer`.
  * Optimization constraints are now declared with human-readable expressions in `Optimizer.add_constraints` (MR [#138](https://gitlab.com/cosapp/cosapp/-/merge_requests/138)).

  Before:
    
  ```python
  from cosapp.drivers import Optimizer
  
  s = SomeSystem('s')
  optim = s.add_driver(Optimizer('optim'))
  
  optim.runner.set_objective('cost')
  optim.runner.add_unknown(['a', 'b', 'p_in.x'])
  # Enter constraints as non-negative expressions:
  optim.runner.add_constraints([
      "b - a",  # b >= a
      "a",      # a >= 0
      "1 - a",  # a <= 1
  ])
  optim.runner.add_constraints(
      "p_out.y",
      inequality = False,  # p_out.y == 0
  )
  
  s.run_drivers()
  ```
  
  After:
    
  ```python
  optim.set_objective('cost')
  optim.add_unknown(['a', 'b', 'p_in.x'])
  optim.add_constraints(
      "b >= a",
      "0 <= a <= 1",
      "p_out.y == 0",
  )
  ```

  * New, convenient iterators and setters for ports (MR [#137](https://gitlab.com/cosapp/cosapp/-/merge_requests/137)):
  
  ```python
  from cosapp.base import Port, System
  
  class XyzPort(Port):
      def setup(self):
          self.add_variable('x')
          self.add_variable('y')
          self.add_variable('z')
  
  class SomeSystem(System):
      def setup(self):
          self.add_input(XyzPort, 'p_in')
          self.add_output(XyzPort, 'p_out')
      
      def compute(self):
          self.p_out.set_from(self.p_in)  # assign values from `p_in`
          self.p_out.z = 0.0
  
  s = SomeSystem('s')
  # Multi-variable setter `set_values`
  s.p_in.set_values(x=1, y=-0.5, z=0.1)
  
  s.run_once()
  # Dict-like (key, value) iterator `items`:
  for varname, value in s.p_out.items():
      print(f"p_out.{varname} = {value})
  ```

### Documentation

* Updated tutorials on ports (MR [#139](https://gitlab.com/cosapp/cosapp/-/merge_requests/139)) and on optimization (MR [#140](https://gitlab.com/cosapp/cosapp/-/merge_requests/140)).

### Bug fixes and code quality

* Fix bug in Jacobian computation for negative perturbations (MR [#129](https://gitlab.com/cosapp/cosapp/-/merge_requests/129)).
* Fix bug in `RunOnce` and `RunSingleCase` recorders with `hold=False` (MR [#130](https://gitlab.com/cosapp/cosapp/-/merge_requests/130)).
* Resolve input aliasing in time driver scenarios (MR [#135](https://gitlab.com/cosapp/cosapp/-/merge_requests/135)).
* Fix bugs with events (MRs [#123](https://gitlab.com/cosapp/cosapp/-/merge_requests/123), [#126](https://gitlab.com/cosapp/cosapp/-/merge_requests/126), [#128](https://gitlab.com/cosapp/cosapp/-/merge_requests/128)).
* Discard empty connectors, and send a warning (MR [#132](https://gitlab.com/cosapp/cosapp/-/merge_requests/132)).
* Other code quality improvements (MRs [#127](https://gitlab.com/cosapp/cosapp/-/merge_requests/127), [#131](https://gitlab.com/cosapp/cosapp/-/merge_requests/131), [#133](https://gitlab.com/cosapp/cosapp/-/merge_requests/133), [#134](https://gitlab.com/cosapp/cosapp/-/merge_requests/134)).

## 0.12.0 (2022-01-17)

### New features

* Implementation of multimode systems and hybrid continuous/discrete time solver (MRs [#100](https://gitlab.com/cosapp/cosapp/-/merge_requests/100), [#103](https://gitlab.com/cosapp/cosapp/-/merge_requests/103), [#105](https://gitlab.com/cosapp/cosapp/-/merge_requests/105)-[#108](https://gitlab.com/cosapp/cosapp/-/merge_requests/108), [#110](https://gitlab.com/cosapp/cosapp/-/merge_requests/110)-[#121](https://gitlab.com/cosapp/cosapp/-/merge_requests/121)):
  * Possibility to declare events and mode variables in systems.
  * New method `System.transition` describing system transition upon the occurrence of events.
  * Event detection in `ExplicitTimeDriver`.

* Possibility to specify a stop criterion in time simulation scenarios (MR [#107](https://gitlab.com/cosapp/cosapp/-/merge_requests/107)).

### Documentation

* New tutorial on hybrid time simulations and multimode systems (MRs [#116](https://gitlab.com/cosapp/cosapp/-/merge_requests/116) and [#120](https://gitlab.com/cosapp/cosapp/-/merge_requests/120)).
* Updated build config file following up a bug fix in [github.com/readthedocs](https://github.com/readthedocs/readthedocs.org) (MR [#109](https://gitlab.com/cosapp/cosapp/-/merge_requests/109)).

## 0.11.8 (2021-11-24)

### New features & API evolutions

* New module `cosapp.base` (MR [#96](https://gitlab.com/cosapp/cosapp/-/merge_requests/96)) containing base classes for user-defined classes (in particular, `Port`, `System` and `Driver`). Also contains `BaseConnector`, base class for custom connectors (see "User-defined and peer-to-peer connectors" below), as well as CoSApp-specific exceptions `ScopeError`, `UnitError` and `ConnectorError`.
**Note:** `Port`, `System` and `Driver` can still be imported from `cosapp.ports`, `cosapp.systems` and `cosapp.drivers`, respectively.

* Public API `cosapp.base.SurrogateModel` to define custom surrogate models used in `System.make_surrogate` (MR [#97](https://gitlab.com/cosapp/cosapp/-/merge_requests/97)).
Pre-defined models have been moved to module `cosapp.utils.surrogate_models`.

* System-to-system connections (MR [#94](https://gitlab.com/cosapp/cosapp/-/merge_requests/94)).

```python
class LegacyPortToPort(System):
    def setup(self):
        a = self.add_child(ModelA('a'))
        b = self.add_child(ModelB('b'))

        # Explicit port-to-port connections
        self.connect(a.p_in, b.p_out)
        self.connect(a.outwards, b.inwards, {'y': 'x'})

class Alternative(System):
  """Same as `LegacyPortToPort`, with alternative connection syntax"""
    def setup(self):
        a = self.add_child(ModelA('a'))
        b = self.add_child(ModelB('b'))

        # Alternative syntax: connect systems, with port or variable mapping
        self.connect(a, b, {'p_in': 'p_out', 'y': 'x'})
```

* User-defined and peer-to-peer connectors (MR [#87](https://gitlab.com/cosapp/cosapp/-/merge_requests/87) and MR [#98](https://gitlab.com/cosapp/cosapp/-/merge_requests/98)).

```python
import numpy
from copy import deepcopy
from cosapp.base import Port, System, BaseConnector

class DeepCopyConnector(BaseConnector):
  """User-defined deep-copy connector"""
    def transfer(self) -> None:
        source, sink = self.source, self.sink

        for target, origin in self.mapping.items():
            value = getattr(source, origin)
            setattr(sink, target, deepcopy(value))

class CustomPort(Port):
    def setup(self):
        self.add_variable('x', 0.0)
        self.add_variable('y', 1.0)

    class Connector(BaseConnector):
      """Connector for peer-to-peer connections"""
        def transfer(self) -> None:
            source, sink = self.source, self.sink
            sink.x = source.y
            sink.y = -source.x

class MyModel(System):
    def setup(self):
        self.add_input(CustomPort, 'p_in')
        self.add_output(CustomPort, 'p_out')

        self.add_inward('entry', numpy.identity(3))
        self.add_outward('exit', numpy.zeros_like(self.entry))

class Assembly(System):
    def setup(self):
        a = self.add_child(MyModel('a'))
        b = self.add_child(MyModel('b'))

        self.connect(a, b, {'exit', 'entry'}, cls=DeepCopyConnector)
        self.connect(a.p_in, b.p_out)  # will use CustomPort.Connector
```

### Documentation

* Updated tutorials (MR [#102](https://gitlab.com/cosapp/cosapp/-/merge_requests/102)).
  * Include latest API evolutions in tutorials on ports and systems.
  * New tutorial on user-defined connectors.
  * New section on user-defined surrogate models.

### Bug fixes and code quality

* Simplify loop resolution (MR [#77](https://gitlab.com/cosapp/cosapp/-/merge_requests/77), [#101](https://gitlab.com/cosapp/cosapp/-/merge_requests/101)).
* Improve connector transfer (MR [#99](https://gitlab.com/cosapp/cosapp/-/merge_requests/99)).
* Update binder settings, to take advantage of prebuilt plotly extension for jupyter lab (MR [#95](https://gitlab.com/cosapp/cosapp/-/merge_requests/95)).
* Other code quality improvements (MR [#76](https://gitlab.com/cosapp/cosapp/-/merge_requests/76), [#82](https://gitlab.com/cosapp/cosapp/-/merge_requests/82), [#90](https://gitlab.com/cosapp/cosapp/-/merge_requests/90)).

## 0.11.7 (2021-09-21)

### New features

* Possibility to define unknowns and equations at solver level (MR [#65](https://gitlab.com/cosapp/cosapp/-/merge_requests/65)).
Minor API evolution facilitating the definition of nonlinear problems and of multi-point design problems.

```python
engine = Turbofan('engine')
solver = engine.add_driver(NonLinearSolver('solver'))

# Add design points:
takeoff = solver.add_child(RunSingleCase('takeoff'))
cruise = solver.add_child(RunSingleCase('cruise'))

# Unknowns defined at solver level regarded as *design* unknowns
solver.add_unknown(['fan.diameter', 'core.turbine.inlet.area'])

# Local off-design equations can be directly defined at case level
takeoff.add_equation('thrust == 1.2e5')
cruise.add_equation('Mach == 0.8')
```

* New recursive iterator `tree()` for systems and drivers, yielding all elements in a composite tree (MR [#68](https://gitlab.com/cosapp/cosapp/-/merge_requests/68)).

```python
head = CompositeSystem('head')

bottom_to_top = [s.name for s in head.tree()]
top_to_bottom = [s.name for s in head.tree(downwards=True)]
```

* Visitor pattern for composite collections of systems, drivers and ports (MR [#68](https://gitlab.com/cosapp/cosapp/-/merge_requests/68)).

```python
from cosapp.patterns.visitor import Visitor, send as send_visitor

class DataCollector(Visitor):
    def __init__(self):
        self.data = {}

    def visit_system(self, system):
        key = system.full_name()
        self.data.setdefault(key, {})
        self.data[key]['children'] = [
            child.name for child in system.children.values()
        ]
        send_visitor(self, system.inputs.values())

    def visit_port(self, port):
        # specify what to do with a port

    def visit_driver(self, driver):
        # specify what to do with a driver

head = CompositeSystem('head')
collector = DataCollector()

send_visitor(collector, head.tree())
print(collector.data)
```

### Documentation

* New tutorials, and new "Tips & Tricks" notebook (MR [#71](https://gitlab.com/cosapp/cosapp/-/merge_requests/71)).

### Bug fixes and code quality

* Improved tests on clean/dirty status (MR [#66](https://gitlab.com/cosapp/cosapp/-/merge_requests/66)).
* Bug fix in tutorial notebook on validation (MR [#67](https://gitlab.com/cosapp/cosapp/-/merge_requests/67)).
* Code quality improvements (MR [#69](https://gitlab.com/cosapp/cosapp/-/merge_requests/69)).
* Make `System.exec_order` a view on `System.children` dictionary keys, rather than an independent attribute (MR [#70](https://gitlab.com/cosapp/cosapp/-/merge_requests/70)). Execution order can still be specified, via a dedicated setter for `exec_order`.
* Fix solver bugs occurring when system structure changes (MR [#73](https://gitlab.com/cosapp/cosapp/-/merge_requests/73)).

## 0.11.6 (2021-06-25)

### Bug fixes and code quality

* Resolve unknown aliasing for pulled input variables (MR [#58](https://gitlab.com/cosapp/cosapp/-/merge_requests/58)).
* Resolve bugs and issues related to `add_target` (MR [#61](https://gitlab.com/cosapp/cosapp/-/merge_requests/61)).
* Fix wrong comparison of Jacobian matrix `jac is None` after converting it as a `numpy` array (MR [#56](https://gitlab.com/cosapp/cosapp/-/merge_requests/56)).
* Set transparent background in `PortMarkdownFormatter` (MR [#59](https://gitlab.com/cosapp/cosapp/-/merge_requests/59)).
* Other code quality improvements (MR [#55](https://gitlab.com/cosapp/cosapp/-/merge_requests/55), [#57](https://gitlab.com/cosapp/cosapp/-/merge_requests/57), [#60](https://gitlab.com/cosapp/cosapp/-/merge_requests/60)).

## 0.11.5 (2021-05-07)

### New features

* **New [binder container](https://mybinder.org/v2/gl/cosapp%2Fcosapp/master?urlpath=lab/tree/docs/tutorials)**,
  allowing anyone to run interactively the tutorials used in the online documentation 
  (MR [#30](https://gitlab.com/cosapp/cosapp/-/merge_requests/30) and [#36](https://gitlab.com/cosapp/cosapp/-/merge_requests/36)).

* **Deferred equations to set targets:**

  New method `add_target`, defining a deferred equation on on a target variable (MR [#48](https://gitlab.com/cosapp/cosapp/-/merge_requests/48)).
  In effect, `add_target` creates an equation whose right-hand side is evaluated dynamically prior to each execution of the nonlienar solver.

  In the example below, the feature is illustrated in design mode. Outward `z` is a function of two independent variables `x` and `y`.
  When design method `'target_z'` is activated, the actual value of `z`, set interactively, is used as a target value, with unknown `y`:
  
```python
class SystemWithTarget(System):
    def setup(self):
        self.add_inward('x', 1.0)
        self.add_inward('y', 1.0)
        self.add_outward('z', 1.0)

        # Define design problem with a target on `z`
        design = self.add_design_method('target_z')
        design.add_unknown('y').add_target('z')

    def compute(self):
        self.z = self.x * self.y**2

s = SystemWithTarget('s')

solver = s.add_driver(NonLinearSolver('solver', tol=1e-9))
# Activate design method 'target_z': outward `z` becomes a target
solver.runner.design.extend(s.design_methods['target_z'])

s.x = 0.5
s.y = 0.5
s.z = 2.0  # set target
s.run_drivers()
assert s.y == pytest.approx(2)  # solution of x * y**2 == 2
assert s.z == pytest.approx(2)

s.z = 4.0  # dynamically set new target
s.run_drivers()
assert s.y == pytest.approx(np.sqrt(8))  # solution of x * y**2 == 4
assert s.z == pytest.approx(4)
```
  Targets can be also be declared in off-design mode, by calling `self.add_target(...)` in `System.setup`.

### Documentation

* Updated tutorials on `System`, `Driver`, and design methods (MR [#41](https://gitlab.com/cosapp/cosapp/-/merge_requests/41)).
* Typo fix and improvements in time driver tutorial (MR [#33](https://gitlab.com/cosapp/cosapp/-/merge_requests/33))

### Bug fixes, minor improvements and code quality

* Report variable name in unit-related Connector warning message (MR [#32](https://gitlab.com/cosapp/cosapp/-/merge_requests/32)).
* Automatically include field `time` in `DataFrame` recorders attached to a time driver (MR [#34](https://gitlab.com/cosapp/cosapp/-/merge_requests/34)).
* Bug fix in `MonteCarlo` driver (MR [#37](https://gitlab.com/cosapp/cosapp/-/merge_requests/37)).
* Replace `conda` by `mamba` in CI scripts (MR [#39](https://gitlab.com/cosapp/cosapp/-/merge_requests/39)).
* Revamp markdown and JS rendering of systems and ports (MR [#40](https://gitlab.com/cosapp/cosapp/-/merge_requests/40) and [#43](https://gitlab.com/cosapp/cosapp/-/merge_requests/43), [#47](https://gitlab.com/cosapp/cosapp/-/merge_requests/47) and [#51](https://gitlab.com/cosapp/cosapp/-/merge_requests/51)).
* Fix bug in `rate` type inference (MR [#44](https://gitlab.com/cosapp/cosapp/-/merge_requests/44)).
* Other code quality improvement (MR [#35](https://gitlab.com/cosapp/cosapp/-/merge_requests/35), [#38](https://gitlab.com/cosapp/cosapp/-/merge_requests/38), [#42](https://gitlab.com/cosapp/cosapp/-/merge_requests/42), [#46](https://gitlab.com/cosapp/cosapp/-/merge_requests/46), [#50](https://gitlab.com/cosapp/cosapp/-/merge_requests/50), [#52](https://gitlab.com/cosapp/cosapp/-/merge_requests/52), [#53](https://gitlab.com/cosapp/cosapp/-/merge_requests/53)).

## 0.11.4 (2021-03-08)

### New features

* Recorders:
  It is now possible to add evaluable expressions in recorders (MR [#27](https://gitlab.com/cosapp/cosapp/-/merge_requests/27)):
  
```python
point = PointMass('point')
driver = point.add_driver(RungeKutta(order=3, time_interval=(0, 2), dt=0.01))

recorder = driver.add_recorder(recorders.DataFrameRecorder(
    includes=['x', 'a', 'norm(v)']),  # norm(v) will be recorded in DataFrame
    period=0.1,
)
```
### Documentation

* New tutorial on `SystemSurrogate` (MR [#15](https://gitlab.com/cosapp/cosapp/-/merge_requests/15)).

### Bug fixes, minor improvements and code quality

* Initialization bug in time simulations (MR [#23](https://gitlab.com/cosapp/cosapp/-/merge_requests/23)).
* Bug in nonlinearity estimation in `NumericalSolver` (MR [#22](https://gitlab.com/cosapp/cosapp/-/merge_requests/22)).
* Do not raise `ArithmeticError` when an unknown is declared several time (MR [#18](https://gitlab.com/cosapp/cosapp/-/merge_requests/18)).
* Suppress deprecation warnings raised by `numpy` (MR [#20](https://gitlab.com/cosapp/cosapp/-/merge_requests/20) and [#24](https://gitlab.com/cosapp/cosapp/-/merge_requests/24)).
* Suppress undue warning raised by `numpy` in `NonLinearSolver` (MR [#19](https://gitlab.com/cosapp/cosapp/-/merge_requests/19)).
* Fix incompatibility between `pandas` and `xlrd` (MR [#21](https://gitlab.com/cosapp/cosapp/-/merge_requests/21)).
* Other code quality improvement (MR [#16](https://gitlab.com/cosapp/cosapp/-/merge_requests/16), [#17](https://gitlab.com/cosapp/cosapp/-/merge_requests/17), [#26](https://gitlab.com/cosapp/cosapp/-/merge_requests/26), [#27](https://gitlab.com/cosapp/cosapp/-/merge_requests/27)).

## 0.11.3 (2020-12-16)

### New features

* Surrogate models:
  It is now possible to create a surrogate model at any system level with new method `System.make_surrogate` (MR [#3](https://gitlab.com/cosapp/cosapp/-/merge_requests/3) and [#12](https://gitlab.com/cosapp/cosapp/-/merge_requests/12)):
  
```python
plane = Aeroplane('plane')  # system with subsystems engine1 and engine2

# Say engine systems have one input parameter `fuel_rate`
# and possibly several outputs, and many sub-systems

# Create training schedule for input data
doe = pandas.DataFrame(
    # loads of input data
    columns=['fuel_rate', 'fan.diameter', ..]  # input names
)
plane.engine1.make_surrogate(doe)  # generates output data and train model

plane.run_once()  # executes the surrogate model of `engine1` instead of original compute()

# dump model to file
plane.engine1.dump_surrogate('engine.bin')
# load model into `engine2`:
plane.engine2.load_surrogate('engine.bin')

# deactivate surrogate model on demand
plane.engine1.active_surrogate = plane.engine2.active_surrogate = False
```

### Bug fixes, minor improvements and code quality

* Add several US-common unit conversions (MR [#2](https://gitlab.com/cosapp/cosapp/-/merge_requests/2)).
* New method to export cosapp system structure into a dictionary (MR [#5](https://gitlab.com/cosapp/cosapp/-/merge_requests/5))
* Make recorders capture port and system properties (MR [#8](https://gitlab.com/cosapp/cosapp/-/merge_requests/8)).
* Fix Module/System naming bug: *'inwards' and 'outwards' are allowed as Module/System names* (MR [#9](https://gitlab.com/cosapp/cosapp/-/merge_requests/9)).
* Broad code quality improvement (MR [#11](https://gitlab.com/cosapp/cosapp/-/merge_requests/11)).

  * Replace `typing.NoReturn` by `None` when appropriate.
  * Rewording pass, typo and error fixes in tutorial notebooks.
  * Suppress a `DeprecationWarning` raised by `numpy` in class `Variable`.
  * Reformat many strings as Python f-strings, for clarity.
  * Symplify many occurrences of `str.join()` for just two elements.

Global rewording of tutorial notebooks, including a few error fixes.

## 0.11.2 (2020-09-28)

First open-source version.
No major code change; mostly updates of license files, URLs in docs, and CI scripts.

## 0.11.1 (2020-07-22)

### Features

* Add the possibility to set boundary condition of transient simulation from interpolate profile.
* Add the possibility to prescribe a maximum step for transient variables.

### Bugs and code quality

* Bug fix in `RunOnce` driver, preventing undue call to `run_once` method.
* Bug fix in AssignString: force copy for numpy arrays.
* New tutorial for advanced features of time simulations in CosApp.

## 0.11.0 (2020-05-12)

### Features

* Improve documentation at various places, add documentation about the cosapp packages structure and sequence diagram for transient simulation.
* Add a advanced logger feature for CoSApp simulations.
* Update FMU export to PythonFMU 0.6.0
* New method `System.add_property` allowing users to create read-only properties.

### Bugs and code quality

* Suppress deprecation warnings raised by external dependencies. 
* Fix bug in AssignString with arrays, `AssignString` of the kind `'x = [0, 1, 2]'` won't change variable `x` into an array of integers,  if `x` is declared as an array of floats.
* Fix `TimeStackUnknown` not able to stack transient variables defined on a children System or with partially pulled transient variable.
* Fix the bug related to the initialization of `rate` attributes in systems.

## 0.10.2 (2020-04-21)

### Features

* [BETA] Export CoSApp System as FMU

### Bugs and code quality

* Apply Broyden correction on Jacobian matrix for iteration without Jacobian update
* Support varying time step
* Fix time not being set before `setup_run` are called.
* Fix reference for residues in `IterativeConnector` (it equals 1. now)
* Drop pyhamcrest for pytest

## 0.10.1 (2020-01-15)

### Features

* Time varying boundary conditions are now possible:

```python
system = MySystem('something')  # system with transient variables x and v
driver = system.add_driver(RungeKutta(time_interval=(0, 2), dt=0.01, order=3))

driver.set_scenario(
    init = {'x': 0.5, 'v': 0},  # initial conditions
    values =
    {
        'omega': 0.7,
        'F_ext': '0.6 * cos(omega * t)'  # explicit time-dependency
    }
)
```

### Bugs and code quality

* Fix various bug on the transient simulation front
* Correct implementation of step limitation in the Newton-Raphson solver
* Using a logger at `DEBUG` level will now display the call stack through the systems and drivers
* Rework of the Python evaluable string to be more efficient

## 0.10.0 (2019-10-23)

* Introduce continuous time simulations with dedicated time drivers (see `TimeDriver` notebook in tutorials).
* Suppress notion of (un)freeze; all variables are considered as known, unless explicitly declared as unknowns.
* Drivers no longer use ports.
* Connectors are now stored by parent system.
* Migrate to pytest.

### API Changes

* Ports:

  * `add_variable("x", units="m", types=Number)` => `add_variable("x", unit="m", dtype=Number)`
  * `freeze` => removed
  * `unfreeze` => replaced by `add_unknown` in Systems and Drivers
  * `connect_to` => replaced by `connect` at system level
  
* Systems:

  * `time_ref` is no longer an argument of method `compute`:
  
    `def compute(self, time_ref):` => `def compute(self):`
       
  * Create a new connection between `a.in1` and `b.out`:
  
    `self.a.in1.connect_to(self.b.out)` => `self.connect(self.a.in1, self.b.out)`
       
  * `add_residues` => `add_equation`
  * `set_numerical_default` => Pass keyword to `add_unknown`
  * `add_inward("x", units="m", types=Number)` => `add_inward("x", unit="m", dtype=Number)`
  * `add_outward("x", units="m", types=Number)` => `add_outward("x", unit="m", dtype=Number)`
  
* Drivers:

  * `add_unknowns(maximal_absolute_step, maximal_relative_step, low_bound, high_bound)` => `add_unknown(max_abs_step, max_rel_step, lower_bound, upper_bound)`
  * `add_equations` => `add_equation`
  * Equations are now represented by a unique string, instead of two strings (left-hand-side, right-hand-side):
  
    `add_equations("a", "b")` => `add_equation("a == b")`  
    
    `add_equations([("x", "2 * y + 1"), ("a", "b")])` => `add_equation(["x == 2 * y + 1", "a == b"])`  
        
  * For `NonLinearSolver`:
  
    `fatol` and `xtol` => `tol`  
    
    `maxiter` => `max_iter`  
        
  * For `Optimizer`:
  
    `ftol` => `tol`
    
    `maxiter` => `max_iter`

## 0.9.6 (2019-10-10)

* More correction for VISjs viewer and System HTML representation

## 0.9.5 (2019-09-25)

* Correct D3 & VISjs Viewers

## 0.9.4 (2019-09-25)

* Introduce an optional environment variable `COSAPP_CONFIG_DIR`

## 0.9.3 (2019-07-25)

### API Changes

* MonteCarlo:

  * `Montecarlo` => `MonteCarlo`
  * `Montecarlo.add_input_vars` => `MonteCarlo.add_random_variable`
  * `Montecarlo.add_response_vars` => `MonteCarlo.add_response`

* MonteCarlo has been improved by using Sobol random generator
* Viewers code on `System` is moved in a subpackage of `cosapp.tools`
* Residue reference is now calculated only once
* Various bug fix

## 0.9.2 (2019-07-01)
* In nonlinear solver, store LU factorization of the Jacobian matrix, rather than its inverse.
* Minor refactoring of the core source code, with no API changes

## 0.9.1 (2019-04-23)

* Create `Variable` class to manage variable attributes
* `watchdog` is now optional
* Configuration is now inside a folder `$HOME/.cosapp.d`
* API changes:
  - `get_latest_solution` => `save_solution`
  - `load_solver_solution` => `load_solution`
* Various bug fix

## 0.9.0 (2019-03-04)

This release introduces lots of API changes:

* Core ports and unit are available in `cosapp.ports`
* Core systems are available in `cosapp.systems`
* Core drivers are available in `cosapp.drivers`
* Core recorders are available in `cosapp.recorders`
* Core tools are available in `cosapp.tools`
* Core notebook tools are available in `cosapp.notebook` (! this is now a separated package)
* `data` have been renamed in `inwards` and `add_data` in `add_inward`
* `locals` have been renamed in `outwards` and `add_locals` in `add_outward`
* `BaseRecorder.record_iteration` renamed in `BaseRecorder.record_state`

- Huge code refractoring: cosapp is now a [Python namespace](https://packaging.python.org/guides/packaging-namespace-packages).
- `cosapp.notebook` has been moved to an independent package `cosapp_notebook`. But it is still accessible from `cosapp.notebook`.
- Introduce *Signal* / *Slot* pattern to connect to internal event (implementation from [signalslot](https://github.com/Numergy/signalslot), included in `cosapp.core.signal`)
    * `Module.setup_ran`: Signal emitted after the `call_setup_run` execution
    * `Module.computed`: Signal emitted after the full `compute` stack (i.e.: `_postcompute`)
    * `Module.clean_ran`: Signal emitted after the `call_clean_run` execution
    * `BaseRecorder.state_recorded`: Signale emitted after the `record_state` execution

## 0.8.0 (2018-10-26)

- Add Jacobian partial matrix update
- Add numerical features to variables to ease convergence control
- Add monitoring of solver residues
- Add restoration of solver result for initialization
- Rework residues and unknowns handling (remove virtual port and pulling port)
- Rework optimizer to be more homogeneous with non-linear solver
- Improve linear Monte Carlo computation time
- Improve data viewer for non-linear solver
- Create viewer for Monte Carlo
- Add dropdown widget for enum variables

## 0.7.0 (2018-09-17)

- Add helper functions to present solver evolutions
- Add new d3 visualization of systems

## 0.6.0 (2018-08-14)

- Implement clean-dirty policy
- Restore compatibility with Python 3.4
- Display influence matrix

## 0.5.0 (2018-07-20)

- Simplify drivers structure, all actions for a case are supported by a single class `RunSingleCase`
- Add support for vector variables; they can be partially (un)frozen and are handled correctly by the solver.
- Add `MonteCarlo` driver
- Add recording data capability

## 0.4.0 (2018-06-15)

- `System` and `Driver` have now a common ancestor `Module` => `Driver` variables are now stored as data or locals
- Add visualization of `System` connections based on N2 graph (syntax: `cosapp.viewmodel(mySystem)`)

## 0.3.0 (2018-04-05)

**API changes:** `System.add_driver` and `Driver.add_child` take now an instance of `Driver`

- Add external code caller System
- Add validation range attributes on variables
- Add variable visibility
- Add metamodel training and DoE generator
- Add helper function to list inputs and outputs variables of a `System`

## 0.2.0 (2018-03-01)

* Stabilization of the user API

## 0.1.0 (2018-01-02)

* First release.

            

Raw data

            {
    "_id": null,
    "home_page": "https://cosapp.readthedocs.io",
    "name": "cosapp",
    "maintainer": null,
    "docs_url": null,
    "requires_python": ">=3.8",
    "maintainer_email": null,
    "keywords": "cosapp, system simulation, system design",
    "author": "CoSApp Development Team",
    "author_email": null,
    "download_url": "https://files.pythonhosted.org/packages/ef/5a/571d1a48a25f49bf4ab2d1b2228a7237cd3b881a0e9f4191948deec076df/cosapp-0.16.0.tar.gz",
    "platform": null,
    "description": "# CoSApp - Collaborative System Approach\n\nThe primary goal of **CoSApp** is to help technical departments in the design of complex systems.\nTo do so, the framework allows the simulation of various systems representing the different parts of the final product in a common environment.\nThe benefit is the ability for each subsystem team to carry out design study with a direct feedback at product level.\n\nThe main features are:\n\n### Butterfly effect\n\nCouple your simulation models with CoSApp to get immediate impact on main product variables and iterate to converge on a better design.\n\n### Design guidance\n\nAll systems can share design parameters associated with an acceptable range.\nYou can take advantage of those limited degrees of freedom without fear of breaking your collaborators' work.\n\n### Flexible simulation workflows\n\nCoSApp solvers can be combined into versatile, customized workflows that fit specific simulation intents.\n\nHave a look at the [introduction](https://cosapp.readthedocs.io/en/stable/tutorials/00-Introduction.html#), containing many tutorials!\n\nThis code is the property of Safran SA.\nIt uses code coming from various open-source projects (see [LICENSE](https://gitlab.com/cosapp/cosapp/blob/master/LICENSE.rst) file).\n\n# Citing\n\nIf you use CoSApp, please cite us!\n\nLac *et al.* (2024), [CoSApp: a Python library to create, simulate and design complex systems](https://doi.org/10.21105/joss.06292), Journal of Open Source Software 9(94), 6292. \n\nBibTeX entry:\n\n```bibtex\n@article{Lac.etal:joss2024, author={\u00c9tienne Lac and Guy {De Spiegeleer} and Adrien Delsalle and Fr\u00e9d\u00e9ric Collonval and Duc-Trung L\u00ea and Mathias Malandain}, title={CoSApp: a Python library to create, simulate and design complex systems}, journal={Journal of Open Source Software}, year={2024}, volume={9}, number={94}, pages={6292}, doi={10.21105/joss.06292}, publisher={The Open Journal}}\n```\n\n# Try it now!\n\nRun a Jupyter Lab instance with binder to try out CoSApp features through examples.\n\n[![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gl/cosapp%2Fcosapp/master?urlpath=lab/tree/docs/tutorials)\n\n# History\n\n\n## 0.16.0 (2024-04-18)\n\n### Bug fixes and code quality\n\n- Primary events triggered within the same time step are now correctly captured (MR [#287](https://gitlab.com/cosapp/cosapp/-/merge_requests/287)).\n  A bug persists when several primary events occur at the exact same time, though, as only one will be retained.\n- Fix bug preventing events from occurring during the first time step of a simulation (MR [#288](https://gitlab.com/cosapp/cosapp/-/merge_requests/288)).\n- Fix a bug causing recorders to crash when inspecting ports with properties (MR [#282](https://gitlab.com/cosapp/cosapp/-/merge_requests/282)).\n- Algebraic and time-dependent problems are now dissociated (MR [#284](https://gitlab.com/cosapp/cosapp/-/merge_requests/284)). As a consequence, invoking `self.problem.clear()` during transitions, for instance, no longer affects time-dependent unknowns such as transients.\n- Fix ambiguous warning message raised by `RunSingleCase` (MR [#279](https://gitlab.com/cosapp/cosapp/-/merge_requests/279)).\n- Various refactoring passes (MRs [#283](https://gitlab.com/cosapp/cosapp/-/merge_requests/283) and [#286](https://gitlab.com/cosapp/cosapp/-/merge_requests/286)).\n\n### Maintenance\n\n- Updated description inside the conda recipe (MR [#276](https://gitlab.com/cosapp/cosapp/-/merge_requests/276)).\n- Pin `pytest` version due to a bug in version 8.1 (MR [#280](https://gitlab.com/cosapp/cosapp/-/merge_requests/280)).\n- Add a \"Citing\" section in the main README file (MR [#281](https://gitlab.com/cosapp/cosapp/-/merge_requests/281)).\n- The module parser was updated (MR [#285](https://gitlab.com/cosapp/cosapp/-/merge_requests/285)).\n- Force `sphinx` < 7.3 in the documentation building environment, owing to an incompatibility with `sphinx-mdinclude` (MR [#289](https://gitlab.com/cosapp/cosapp/-/merge_requests/289)). This is a temporary patch until root cause is fixed.\n\n\n## 0.15.4 (2024-02-28)\n\n### Bug fixes and code quality\n\n- Fix bug raised in `NonLinearSolver` for systems with rates (MR [#268](https://gitlab.com/cosapp/cosapp/-/merge_requests/268)).\n- Minor refactoring pass (MR [#274](https://gitlab.com/cosapp/cosapp/-/merge_requests/274)).\n\n### Maintenance\n\n- Drop Python 3.8 support and add Python 3.11 test pipeline (MR [#270](https://gitlab.com/cosapp/cosapp/-/merge_requests/270)).\n- Update installation and contribution guidelines (MR [#270](https://gitlab.com/cosapp/cosapp/-/merge_requests/270)).\n- Update dependency list (MRs [#269](https://gitlab.com/cosapp/cosapp/-/merge_requests/269) and [#270](https://gitlab.com/cosapp/cosapp/-/merge_requests/270)).\n\n### JOSS article\n\nPublication of an article on CoSApp in the [Journal of Open-Source Software](https://joss.theoj.org/), referenced to version 0.15.4 (MR [#271](https://gitlab.com/cosapp/cosapp/-/merge_requests/271)).\n\n\n## 0.15.3 (2023-12-19)\n\n### Bug fixes and code quality\n\n- Fix minor bug in `NonLinearSolver` (MR [#261](https://gitlab.com/cosapp/cosapp/-/merge_requests/261)).\n- Fix incorrect return type hints in `System` (MR [#259](https://gitlab.com/cosapp/cosapp/-/merge_requests/259)).\n- Improve support for read-only properties in system getters and setters (MR [#264](https://gitlab.com/cosapp/cosapp/-/merge_requests/264)).\n\n### Maintenance\n\n- Remove deprecated dependency for compatibility with Python 3.12 (MR [#258](https://gitlab.com/cosapp/cosapp/-/merge_requests/258)).\n- Force `pythonfmu` < 0.6.3 in dependency list, to prevent a crash during tests (MR [#262](https://gitlab.com/cosapp/cosapp/-/merge_requests/262)). Temporary fix until root cause is identified.\n\n\n## 0.15.2 (2023-10-14)\n\n### Bug fixes\n\n- Fix crash with `VisJs` rendering of sub-systems (MR [#252](https://gitlab.com/cosapp/cosapp/-/merge_requests/252)).\n- Fix minor bug in `EvalString` (MR [#253](https://gitlab.com/cosapp/cosapp/-/merge_requests/253)).\n- Fix bad synchronization of mode variables during transitions (MR [#254](https://gitlab.com/cosapp/cosapp/-/merge_requests/254)).\n- Improve error message when pulling variables with different roles (MR [#255](https://gitlab.com/cosapp/cosapp/-/merge_requests/255)).\n- Fix `TypeError` when passing `pulling` argument as a tuple in `System.add_child` (MR [#256](https://gitlab.com/cosapp/cosapp/-/merge_requests/256)).\n\n\n## 0.15.1 (2023-09-18)\n\n### New features & API changes\n\n- The representation of `MathematicalProblem` objects now indicates the number of unknowns and equations, for a better readability (MR [#249](https://gitlab.com/cosapp/cosapp/-/merge_requests/249)).\n- Optional argument `execution_index` in `System.add_child` and `Driver.add_child` can now take a negative value, with a behaviour following that of `list.insert` (MR [#250](https://gitlab.com/cosapp/cosapp/-/merge_requests/250)).\n\n### Bug fixes and code quality\n\n- Add missing field \"time\" in `ExplicitTimeRecorder.event_data`, when no recorder is set (MR [#245](https://gitlab.com/cosapp/cosapp/-/merge_requests/245)).\n- Fix bug with recorders inspecting systems with iterators (MRs [#246](https://gitlab.com/cosapp/cosapp/-/merge_requests/246) and [#247](https://gitlab.com/cosapp/cosapp/-/merge_requests/247)).\n- Fix bug with `NonLinearSolver` with NumPy array residues (MR [#248](https://gitlab.com/cosapp/cosapp/-/merge_requests/248)).\n- Fix initialization bug of targets involving expressions (MR [#249](https://gitlab.com/cosapp/cosapp/-/merge_requests/249)).\n\n\n## 0.15.0 (2023-07-20)\n\n### New features & API changes\n\n- Suppression of default `RunSingleCase` subdriver `runner` in `NonLinearSolver` drivers (MR [#239](https://gitlab.com/cosapp/cosapp/-/merge_requests/239)).\n- Enable target initialization in multi-point design problems (MR [#233](https://gitlab.com/cosapp/cosapp/-/merge_requests/233)).\n- New utility function `swap_system` to replace on the fly a subsystem by another `System` instance (MR [#238](https://gitlab.com/cosapp/cosapp/-/merge_requests/238)).\n\n### Bug fixes and code quality\n\n- Refactor driver `Optimizer` (MR [#240](https://gitlab.com/cosapp/cosapp/-/merge_requests/240)).\n- Various bug fixes (MRs [#234](https://gitlab.com/cosapp/cosapp/-/merge_requests/234), [#235](https://gitlab.com/cosapp/cosapp/-/merge_requests/235), [#241](https://gitlab.com/cosapp/cosapp/-/merge_requests/241)).\n\n### Documentation\n\n- New tutorial on `swap_system` (MR [#243](https://gitlab.com/cosapp/cosapp/-/merge_requests/243)).\n- General update of tutorials (MRs [#232](https://gitlab.com/cosapp/cosapp/-/merge_requests/232) and [#242](https://gitlab.com/cosapp/cosapp/-/merge_requests/242)).\n\n\n## 0.14.1 (2023-06-08)\n\n### Bug fixes and code quality\n\n- Fix incorrect output file name in `cosapp.tools.parse_module` (MR [#229](https://gitlab.com/cosapp/cosapp/-/merge_requests/229)).\n- Refactoring pass (MR [#230](https://gitlab.com/cosapp/cosapp/-/merge_requests/230)).\n\n### Documentation\n\n- Upgrade documentation build stack (MRs [#224](https://gitlab.com/cosapp/cosapp/-/merge_requests/224) and [#226](https://gitlab.com/cosapp/cosapp/-/merge_requests/226)).\n- Fix bad rendering of ports and systems (MRs [#227](https://gitlab.com/cosapp/cosapp/-/merge_requests/227) and [#228](https://gitlab.com/cosapp/cosapp/-/merge_requests/228)).\n\n\n## 0.14.0 (2023-05-17)\n\n### New features & API changes\n\n* Improved performance, through a revised clean/dirty mechanism (MR [#215](https://gitlab.com/cosapp/cosapp/-/merge_requests/215)).\n* Possibility to add a contextual description to sub-systems and ports of a system, as well as sub-drivers (MR [#216](https://gitlab.com/cosapp/cosapp/-/merge_requests/216)). This feature is useful for automatic documentation tools, and has been included in the Markdown representation of systems (also used in function `cosapp.tools.display_doc`). Example:\n  \n  ```python\n  from cosapp.base import System\n  from my_module import FlowPort\n  \n  class MySystem(System):\n      def setup(self):\n          self.add_input(FlowPort, \"fl_in1\", desc=\"Primary inlet flow port\")\n          self.add_input(FlowPort, \"fl_in2\", desc=\"Secondary inlet flow port\")\n  \n          self.add_output(FlowPort, \"fl_out\")\n  ```\n  \n* New hook function `_parse_module_config`, returning pre-defined settings for `cosapp.tools.parse_module` (MR [#218](https://gitlab.com/cosapp/cosapp/-/merge_requests/218)). This allows module maintainers to simply call\n  \n  ```python\n  from cosapp.tools import parse_module\n  import my_module\n  \n  parse_module(my_module)\n  ```\n\n  instead of, *e.g.*,\n\n  ```python\n  parse_module(\n      my_module,\n      ctor_config={\n          \"ComplexSystem1\": [\n              dict(n=1, foo=0.5),\n              dict(n=2, foo=0.1),\n          ],\n          \"ComplexSystem2\": [\n              dict(xi=0.0, __alias__=\"ComplexSystem2_a\"),\n              dict(xi=1.0, __alias__=\"ComplexSystem2_b\"),\n          ],\n      },\n      excludes=[\"Foo*\", \"*Bar?\"],\n  )\n  ```\n\n  provided `my_module._parse_module_config()` returns a dictionary specifying the values of `ctor_config`, `excludes`, *etc.*\n\n* Make `SolverResults` a `dataclass`, for easier handling of `NonLinearSolver.results`, *e.g.* (MR [#220](https://gitlab.com/cosapp/cosapp/-/merge_requests/220)).\n* Expose attribute `problem` in system setup (MR [#221](https://gitlab.com/cosapp/cosapp/-/merge_requests/221)). Previously, `problem` was only exposed in method `System.transition`.\n\n### Bug fixes and code quality\n\n* Fix bug in `NonLinearSolver` log message (MR [#214](https://gitlab.com/cosapp/cosapp/-/merge_requests/214)).\n* Add missing JSON file in PyPI and conda packages, preventing the use of `cosapp.tools.parse_module` (MR [#219](https://gitlab.com/cosapp/cosapp/-/merge_requests/219)).\n\n### Documentation\n\n* Illustrate port and sub-system description in tutorials (MR [#215](https://gitlab.com/cosapp/cosapp/-/merge_requests/215)).\n\n\n## 0.13.1 (2023-04-03)\n\n### Bug fixes and code quality\n\n* Update test baseline to pass in a Python 3.11 environment (MR [#200](https://gitlab.com/cosapp/cosapp/-/merge_requests/200)).\n* Creation of a dummy system factory, mostly for tests (MR [#201](https://gitlab.com/cosapp/cosapp/-/merge_requests/201)).\n* Improve clean/dirty mechanism (MR [#202](https://gitlab.com/cosapp/cosapp/-/merge_requests/202)) and fix incorrect clean/dirty status with surrogate models (MR [#205](https://gitlab.com/cosapp/cosapp/-/merge_requests/205)).\n* Fix bug in function `cosapp.tools.display_doc` for classes with setup arguments (MR [#208](https://gitlab.com/cosapp/cosapp/-/merge_requests/208)).\n* Various code quality improvements (MRs [#211](https://gitlab.com/cosapp/cosapp/-/merge_requests/211), [#212](https://gitlab.com/cosapp/cosapp/-/merge_requests/212)).\n\n### Documentation\n\nNote: extensive use of self-documenting f-strings (introduced in Python 3.8) has made tutorials incompatible with Python 3.7.\n\n* Updated tutorials (MRs [#203](https://gitlab.com/cosapp/cosapp/-/merge_requests/203), [#206](https://gitlab.com/cosapp/cosapp/-/merge_requests/206), [#207](https://gitlab.com/cosapp/cosapp/-/merge_requests/207), [#210](https://gitlab.com/cosapp/cosapp/-/merge_requests/210)).\n* The image used in binder is now based on Python 3.10 (MR [#204](https://gitlab.com/cosapp/cosapp/-/merge_requests/204)).\n\n### Module parser\n\n* New function `parse_module` in `cosapp.tools` collecting all system and port classes within a Python module. This parser, generating a JSON file containing the description of all CoSApp symbols, is primarily meant to be used for constructional GUI applications, developed separately (MRs [#192](https://gitlab.com/cosapp/cosapp/-/merge_requests/192) & [#209](https://gitlab.com/cosapp/cosapp/-/merge_requests/209)).\n\n\n## 0.13.0 (2023-02-09)\n\n### Python 3.10 support\n\nThe code is now tested for Python 3.8, 3.9 and 3.10.\nSupport of Python 3.7 is thus officially dropped, although no version-specific Python code was introduced in this version of CoSApp.\n\n### New features & API changes\n\n* Module `connectors` moved from `cosapp.core` to `cosapp.ports` (MR [#189](https://gitlab.com/cosapp/cosapp/-/merge_requests/189)).\n* New \"direct\" (with no unit conversion) connector classes `PlainConnector`, `CopyConnector` and `DeepCopyConnector`, in `cosapp.ports.connectors` (MR [#188](https://gitlab.com/cosapp/cosapp/-/merge_requests/188)).\n* New method `MathematicalProblem.is_empty()`, equivalent to `shape == (0, 0)` (MR [#186](https://gitlab.com/cosapp/cosapp/-/merge_requests/186)).\n* Improved VisJs graph rendering, by limiting node size for long system names (MR [#184](https://gitlab.com/cosapp/cosapp/-/merge_requests/184)).\n* New utility functions `get_state` and `set_state` in `cosapp.utils`, for quick system data recovery (MR [#193](https://gitlab.com/cosapp/cosapp/-/merge_requests/193)):\n\n  ```python\n  from cosapp.utils import get_state, set_state\n  \n  s = SomeSystem('s')\n  # ... many design steps, say\n  \n  # Save state in local object\n  designed = get_state(s)\n  \n  s.drivers.clear()\n  s.add_driver(SomeDriver('driver'))\n  \n  try:\n      s.run_drivers()\n  except:\n      # Recover previous state\n      set_state(s, designed)\n  ```\n\n* Functions `radians`, `degrees` and `arctan2`/`atan2` have been added to the scope of `EvalString` objects, and can therefore be used in equations, *e.g.* (MR [#178](https://gitlab.com/cosapp/cosapp/-/merge_requests/178)).\n* Recorders can now record constant properties (MR [#181](https://gitlab.com/cosapp/cosapp/-/merge_requests/181)).\n* Deprecation of `System.get_unsolved_problem` in favour of new method `assembled_problem` (MR [#174](https://gitlab.com/cosapp/cosapp/-/merge_requests/174)).\n* Inner off-design problem of systems is now exposed as attribute `problem`, but only within the `transition` method (MR [#174](https://gitlab.com/cosapp/cosapp/-/merge_requests/174)). This allows users to add or remove off-design constraints during event-driven transitions, while keeping this property inaccessible the rest of the time.\n\n  ```python\n  from cosapp.base import System\n  from math import sin, cos\n  \n  class SomeSystem(System):\n      def setup(self):\n          self.add_inward('x', 0.0)\n          self.add_inward('y', 0.0)\n          self.add_outward('z', 0.0)\n          a = self.add_event('event_a', trigger='x > y')\n          b = self.add_event('event_b', trigger='x < y')\n      \n      def compute(self):\n          self.z = cos(self.x) * sin(self.y)\n  \n      def transition(self):\n          offdesign = self.problem\n          if self.event_a.present:\n              offdesign.clear()\n              offdesign.add_equation('z == 0.5').add_unknown('x')\n          if self.event_b.present:\n              offdesign.clear()\n  ```\n\n### Bug fixes and code quality\n\n* Fix serialization bugs for systems with setup parameters (MR [#180](https://gitlab.com/cosapp/cosapp/-/merge_requests/180)) and `None` variables (MR [#172](https://gitlab.com/cosapp/cosapp/-/merge_requests/172)).\n* Bug fix on event time calculation involving array transients (MR [#177](https://gitlab.com/cosapp/cosapp/-/merge_requests/177)).\n* Bug fix on possible name conflicts in connector storage (MR [#173](https://gitlab.com/cosapp/cosapp/-/merge_requests/173)).\n* Fix inconsistent behaviour of `System.add_child` when a `pulling` error is raised (MR [#197](https://gitlab.com/cosapp/cosapp/-/merge_requests/197)).\n* Various code quality improvements (MRs [#175](https://gitlab.com/cosapp/cosapp/-/merge_requests/175), [#185](https://gitlab.com/cosapp/cosapp/-/merge_requests/185), [#186](https://gitlab.com/cosapp/cosapp/-/merge_requests/186), [#187](https://gitlab.com/cosapp/cosapp/-/merge_requests/187), [#190](https://gitlab.com/cosapp/cosapp/-/merge_requests/190), [#191](https://gitlab.com/cosapp/cosapp/-/merge_requests/191), [#194](https://gitlab.com/cosapp/cosapp/-/merge_requests/194)).\n\n### Documentation\n\n* Updated time driver tutorial (MR [#182](https://gitlab.com/cosapp/cosapp/-/merge_requests/182)).\n* Updated Tips & Tricks (MR [#196](https://gitlab.com/cosapp/cosapp/-/merge_requests/196)).\n* Other updates (MRs [#176](https://gitlab.com/cosapp/cosapp/-/merge_requests/176), [#195](https://gitlab.com/cosapp/cosapp/-/merge_requests/195), [#198](https://gitlab.com/cosapp/cosapp/-/merge_requests/198)).\n\n## 0.12.3 (2022-09-21)\n\n### New features & API changes\n\n* Improved user experience:\n  * Auto-completion for dynamically added attributes of systems (ports, subsystems, inwards, outwards, events...) and drivers (sub-drivers) (MRs [#164](https://gitlab.com/cosapp/cosapp/-/merge_requests/164) and [#166](https://gitlab.com/cosapp/cosapp/-/merge_requests/166));\n  * Improved representation of mathematical problems, in particular for loop equations and multi-point design problems (MRs [#159](https://gitlab.com/cosapp/cosapp/-/merge_requests/159), [#160](https://gitlab.com/cosapp/cosapp/-/merge_requests/160) and [#163](https://gitlab.com/cosapp/cosapp/-/merge_requests/163)).\n* New method `System.new_problem` to facilitate the creation of dynamic design methods, *e.g.* (MR [#162](https://gitlab.com/cosapp/cosapp/-/merge_requests/162)).\n\n### Documentation\n\n* Updated tutorials (MRs [#169](https://gitlab.com/cosapp/cosapp/-/merge_requests/169) and [#170](https://gitlab.com/cosapp/cosapp/-/merge_requests/170)).\n\n### Bug fixes and code quality\n\n* Bug fix on unknown dealiasing (MR [#157](https://gitlab.com/cosapp/cosapp/-/merge_requests/157)).\n* Bug fix on port variable export (MR [#158](https://gitlab.com/cosapp/cosapp/-/merge_requests/158)).\n* Bug fix on system serialization (MR [#161](https://gitlab.com/cosapp/cosapp/-/merge_requests/161)).\n* Bug fix on subsystem read-only constants (MR [#167](https://gitlab.com/cosapp/cosapp/-/merge_requests/167)).\n* Various code quality improvements (MRs [#154](https://gitlab.com/cosapp/cosapp/-/merge_requests/154), [#155](https://gitlab.com/cosapp/cosapp/-/merge_requests/155), [#162](https://gitlab.com/cosapp/cosapp/-/merge_requests/162), [#168](https://gitlab.com/cosapp/cosapp/-/merge_requests/168)).\n\n## 0.12.2 (2022-05-26)\n\n### New features & API changes\n\n* Automatic tolerance in `NonLinearSolver` (MRs [#148](https://gitlab.com/cosapp/cosapp/-/merge_requests/148) and [#152](https://gitlab.com/cosapp/cosapp/-/merge_requests/152)).\n* `Optimizer.set_objective` is deprecated, in favour of `set_minimum` and `set_maximum` (MR [#150](https://gitlab.com/cosapp/cosapp/-/merge_requests/150)).\n* Loop residues are no longer normalized (MR [#151](https://gitlab.com/cosapp/cosapp/-/merge_requests/151)).\n* Improved type hints for ports, systems and drivers, in functions whose return type depends on arguments, such as `System.add_child`, `add_driver`, *etc.* (MR [#145](https://gitlab.com/cosapp/cosapp/-/merge_requests/145)).\n\n### Documentation\n\n* Updated tutorials (MRs [#144](https://gitlab.com/cosapp/cosapp/-/merge_requests/144), [#147](https://gitlab.com/cosapp/cosapp/-/merge_requests/147) and [#154](https://gitlab.com/cosapp/cosapp/-/merge_requests/154)).\n\n### Bug fixes and code quality\n\n* Fix inconsistent behaviour of recorders (MR [#143](https://gitlab.com/cosapp/cosapp/-/merge_requests/143)).\n* Fix bug on event initialization (MR [#146](https://gitlab.com/cosapp/cosapp/-/merge_requests/146)).\n* Fix bad markdown formatting of ports occurring in `jupyterlab` 3.4 (MR [#149](https://gitlab.com/cosapp/cosapp/-/merge_requests/149)).\n* Fix failed test caused by a regression in `pytest` 7.1 (MR [#142](https://gitlab.com/cosapp/cosapp/-/merge_requests/142)).\n\n## 0.12.1 (2022-02-25)\n\n### New features & API changes\n\n* Simplification of driver `Optimizer`:\n  * Suppression of sub-driver `runner` (MR [#136](https://gitlab.com/cosapp/cosapp/-/merge_requests/136)). This change introduces new methods `set_objective`, `add_unknowns` and `add_constraints` in driver `Optimizer`.\n  * Optimization constraints are now declared with human-readable expressions in `Optimizer.add_constraints` (MR [#138](https://gitlab.com/cosapp/cosapp/-/merge_requests/138)).\n\n  Before:\n    \n  ```python\n  from cosapp.drivers import Optimizer\n  \n  s = SomeSystem('s')\n  optim = s.add_driver(Optimizer('optim'))\n  \n  optim.runner.set_objective('cost')\n  optim.runner.add_unknown(['a', 'b', 'p_in.x'])\n  # Enter constraints as non-negative expressions:\n  optim.runner.add_constraints([\n      \"b - a\",  # b >= a\n      \"a\",      # a >= 0\n      \"1 - a\",  # a <= 1\n  ])\n  optim.runner.add_constraints(\n      \"p_out.y\",\n      inequality = False,  # p_out.y == 0\n  )\n  \n  s.run_drivers()\n  ```\n  \n  After:\n    \n  ```python\n  optim.set_objective('cost')\n  optim.add_unknown(['a', 'b', 'p_in.x'])\n  optim.add_constraints(\n      \"b >= a\",\n      \"0 <= a <= 1\",\n      \"p_out.y == 0\",\n  )\n  ```\n\n  * New, convenient iterators and setters for ports (MR [#137](https://gitlab.com/cosapp/cosapp/-/merge_requests/137)):\n  \n  ```python\n  from cosapp.base import Port, System\n  \n  class XyzPort(Port):\n      def setup(self):\n          self.add_variable('x')\n          self.add_variable('y')\n          self.add_variable('z')\n  \n  class SomeSystem(System):\n      def setup(self):\n          self.add_input(XyzPort, 'p_in')\n          self.add_output(XyzPort, 'p_out')\n      \n      def compute(self):\n          self.p_out.set_from(self.p_in)  # assign values from `p_in`\n          self.p_out.z = 0.0\n  \n  s = SomeSystem('s')\n  # Multi-variable setter `set_values`\n  s.p_in.set_values(x=1, y=-0.5, z=0.1)\n  \n  s.run_once()\n  # Dict-like (key, value) iterator `items`:\n  for varname, value in s.p_out.items():\n      print(f\"p_out.{varname} = {value})\n  ```\n\n### Documentation\n\n* Updated tutorials on ports (MR [#139](https://gitlab.com/cosapp/cosapp/-/merge_requests/139)) and on optimization (MR [#140](https://gitlab.com/cosapp/cosapp/-/merge_requests/140)).\n\n### Bug fixes and code quality\n\n* Fix bug in Jacobian computation for negative perturbations (MR [#129](https://gitlab.com/cosapp/cosapp/-/merge_requests/129)).\n* Fix bug in `RunOnce` and `RunSingleCase` recorders with `hold=False` (MR [#130](https://gitlab.com/cosapp/cosapp/-/merge_requests/130)).\n* Resolve input aliasing in time driver scenarios (MR [#135](https://gitlab.com/cosapp/cosapp/-/merge_requests/135)).\n* Fix bugs with events (MRs [#123](https://gitlab.com/cosapp/cosapp/-/merge_requests/123), [#126](https://gitlab.com/cosapp/cosapp/-/merge_requests/126), [#128](https://gitlab.com/cosapp/cosapp/-/merge_requests/128)).\n* Discard empty connectors, and send a warning (MR [#132](https://gitlab.com/cosapp/cosapp/-/merge_requests/132)).\n* Other code quality improvements (MRs [#127](https://gitlab.com/cosapp/cosapp/-/merge_requests/127), [#131](https://gitlab.com/cosapp/cosapp/-/merge_requests/131), [#133](https://gitlab.com/cosapp/cosapp/-/merge_requests/133), [#134](https://gitlab.com/cosapp/cosapp/-/merge_requests/134)).\n\n## 0.12.0 (2022-01-17)\n\n### New features\n\n* Implementation of multimode systems and hybrid continuous/discrete time solver (MRs [#100](https://gitlab.com/cosapp/cosapp/-/merge_requests/100), [#103](https://gitlab.com/cosapp/cosapp/-/merge_requests/103), [#105](https://gitlab.com/cosapp/cosapp/-/merge_requests/105)-[#108](https://gitlab.com/cosapp/cosapp/-/merge_requests/108), [#110](https://gitlab.com/cosapp/cosapp/-/merge_requests/110)-[#121](https://gitlab.com/cosapp/cosapp/-/merge_requests/121)):\n  * Possibility to declare events and mode variables in systems.\n  * New method `System.transition` describing system transition upon the occurrence of events.\n  * Event detection in `ExplicitTimeDriver`.\n\n* Possibility to specify a stop criterion in time simulation scenarios (MR [#107](https://gitlab.com/cosapp/cosapp/-/merge_requests/107)).\n\n### Documentation\n\n* New tutorial on hybrid time simulations and multimode systems (MRs [#116](https://gitlab.com/cosapp/cosapp/-/merge_requests/116) and [#120](https://gitlab.com/cosapp/cosapp/-/merge_requests/120)).\n* Updated build config file following up a bug fix in [github.com/readthedocs](https://github.com/readthedocs/readthedocs.org) (MR [#109](https://gitlab.com/cosapp/cosapp/-/merge_requests/109)).\n\n## 0.11.8 (2021-11-24)\n\n### New features & API evolutions\n\n* New module `cosapp.base` (MR [#96](https://gitlab.com/cosapp/cosapp/-/merge_requests/96)) containing base classes for user-defined classes (in particular, `Port`, `System` and `Driver`). Also contains `BaseConnector`, base class for custom connectors (see \"User-defined and peer-to-peer connectors\" below), as well as CoSApp-specific exceptions `ScopeError`, `UnitError` and `ConnectorError`.\n**Note:** `Port`, `System` and `Driver` can still be imported from `cosapp.ports`, `cosapp.systems` and `cosapp.drivers`, respectively.\n\n* Public API `cosapp.base.SurrogateModel` to define custom surrogate models used in `System.make_surrogate` (MR [#97](https://gitlab.com/cosapp/cosapp/-/merge_requests/97)).\nPre-defined models have been moved to module `cosapp.utils.surrogate_models`.\n\n* System-to-system connections (MR [#94](https://gitlab.com/cosapp/cosapp/-/merge_requests/94)).\n\n```python\nclass LegacyPortToPort(System):\n    def setup(self):\n        a = self.add_child(ModelA('a'))\n        b = self.add_child(ModelB('b'))\n\n        # Explicit port-to-port connections\n        self.connect(a.p_in, b.p_out)\n        self.connect(a.outwards, b.inwards, {'y': 'x'})\n\nclass Alternative(System):\n  \"\"\"Same as `LegacyPortToPort`, with alternative connection syntax\"\"\"\n    def setup(self):\n        a = self.add_child(ModelA('a'))\n        b = self.add_child(ModelB('b'))\n\n        # Alternative syntax: connect systems, with port or variable mapping\n        self.connect(a, b, {'p_in': 'p_out', 'y': 'x'})\n```\n\n* User-defined and peer-to-peer connectors (MR [#87](https://gitlab.com/cosapp/cosapp/-/merge_requests/87) and MR [#98](https://gitlab.com/cosapp/cosapp/-/merge_requests/98)).\n\n```python\nimport numpy\nfrom copy import deepcopy\nfrom cosapp.base import Port, System, BaseConnector\n\nclass DeepCopyConnector(BaseConnector):\n  \"\"\"User-defined deep-copy connector\"\"\"\n    def transfer(self) -> None:\n        source, sink = self.source, self.sink\n\n        for target, origin in self.mapping.items():\n            value = getattr(source, origin)\n            setattr(sink, target, deepcopy(value))\n\nclass CustomPort(Port):\n    def setup(self):\n        self.add_variable('x', 0.0)\n        self.add_variable('y', 1.0)\n\n    class Connector(BaseConnector):\n      \"\"\"Connector for peer-to-peer connections\"\"\"\n        def transfer(self) -> None:\n            source, sink = self.source, self.sink\n            sink.x = source.y\n            sink.y = -source.x\n\nclass MyModel(System):\n    def setup(self):\n        self.add_input(CustomPort, 'p_in')\n        self.add_output(CustomPort, 'p_out')\n\n        self.add_inward('entry', numpy.identity(3))\n        self.add_outward('exit', numpy.zeros_like(self.entry))\n\nclass Assembly(System):\n    def setup(self):\n        a = self.add_child(MyModel('a'))\n        b = self.add_child(MyModel('b'))\n\n        self.connect(a, b, {'exit', 'entry'}, cls=DeepCopyConnector)\n        self.connect(a.p_in, b.p_out)  # will use CustomPort.Connector\n```\n\n### Documentation\n\n* Updated tutorials (MR [#102](https://gitlab.com/cosapp/cosapp/-/merge_requests/102)).\n  * Include latest API evolutions in tutorials on ports and systems.\n  * New tutorial on user-defined connectors.\n  * New section on user-defined surrogate models.\n\n### Bug fixes and code quality\n\n* Simplify loop resolution (MR [#77](https://gitlab.com/cosapp/cosapp/-/merge_requests/77), [#101](https://gitlab.com/cosapp/cosapp/-/merge_requests/101)).\n* Improve connector transfer (MR [#99](https://gitlab.com/cosapp/cosapp/-/merge_requests/99)).\n* Update binder settings, to take advantage of prebuilt plotly extension for jupyter lab (MR [#95](https://gitlab.com/cosapp/cosapp/-/merge_requests/95)).\n* Other code quality improvements (MR [#76](https://gitlab.com/cosapp/cosapp/-/merge_requests/76), [#82](https://gitlab.com/cosapp/cosapp/-/merge_requests/82), [#90](https://gitlab.com/cosapp/cosapp/-/merge_requests/90)).\n\n## 0.11.7 (2021-09-21)\n\n### New features\n\n* Possibility to define unknowns and equations at solver level (MR [#65](https://gitlab.com/cosapp/cosapp/-/merge_requests/65)).\nMinor API evolution facilitating the definition of nonlinear problems and of multi-point design problems.\n\n```python\nengine = Turbofan('engine')\nsolver = engine.add_driver(NonLinearSolver('solver'))\n\n# Add design points:\ntakeoff = solver.add_child(RunSingleCase('takeoff'))\ncruise = solver.add_child(RunSingleCase('cruise'))\n\n# Unknowns defined at solver level regarded as *design* unknowns\nsolver.add_unknown(['fan.diameter', 'core.turbine.inlet.area'])\n\n# Local off-design equations can be directly defined at case level\ntakeoff.add_equation('thrust == 1.2e5')\ncruise.add_equation('Mach == 0.8')\n```\n\n* New recursive iterator `tree()` for systems and drivers, yielding all elements in a composite tree (MR [#68](https://gitlab.com/cosapp/cosapp/-/merge_requests/68)).\n\n```python\nhead = CompositeSystem('head')\n\nbottom_to_top = [s.name for s in head.tree()]\ntop_to_bottom = [s.name for s in head.tree(downwards=True)]\n```\n\n* Visitor pattern for composite collections of systems, drivers and ports (MR [#68](https://gitlab.com/cosapp/cosapp/-/merge_requests/68)).\n\n```python\nfrom cosapp.patterns.visitor import Visitor, send as send_visitor\n\nclass DataCollector(Visitor):\n    def __init__(self):\n        self.data = {}\n\n    def visit_system(self, system):\n        key = system.full_name()\n        self.data.setdefault(key, {})\n        self.data[key]['children'] = [\n            child.name for child in system.children.values()\n        ]\n        send_visitor(self, system.inputs.values())\n\n    def visit_port(self, port):\n        # specify what to do with a port\n\n    def visit_driver(self, driver):\n        # specify what to do with a driver\n\nhead = CompositeSystem('head')\ncollector = DataCollector()\n\nsend_visitor(collector, head.tree())\nprint(collector.data)\n```\n\n### Documentation\n\n* New tutorials, and new \"Tips & Tricks\" notebook (MR [#71](https://gitlab.com/cosapp/cosapp/-/merge_requests/71)).\n\n### Bug fixes and code quality\n\n* Improved tests on clean/dirty status (MR [#66](https://gitlab.com/cosapp/cosapp/-/merge_requests/66)).\n* Bug fix in tutorial notebook on validation (MR [#67](https://gitlab.com/cosapp/cosapp/-/merge_requests/67)).\n* Code quality improvements (MR [#69](https://gitlab.com/cosapp/cosapp/-/merge_requests/69)).\n* Make `System.exec_order` a view on `System.children` dictionary keys, rather than an independent attribute (MR [#70](https://gitlab.com/cosapp/cosapp/-/merge_requests/70)). Execution order can still be specified, via a dedicated setter for `exec_order`.\n* Fix solver bugs occurring when system structure changes (MR [#73](https://gitlab.com/cosapp/cosapp/-/merge_requests/73)).\n\n## 0.11.6 (2021-06-25)\n\n### Bug fixes and code quality\n\n* Resolve unknown aliasing for pulled input variables (MR [#58](https://gitlab.com/cosapp/cosapp/-/merge_requests/58)).\n* Resolve bugs and issues related to `add_target` (MR [#61](https://gitlab.com/cosapp/cosapp/-/merge_requests/61)).\n* Fix wrong comparison of Jacobian matrix `jac is None` after converting it as a `numpy` array (MR [#56](https://gitlab.com/cosapp/cosapp/-/merge_requests/56)).\n* Set transparent background in `PortMarkdownFormatter` (MR [#59](https://gitlab.com/cosapp/cosapp/-/merge_requests/59)).\n* Other code quality improvements (MR [#55](https://gitlab.com/cosapp/cosapp/-/merge_requests/55), [#57](https://gitlab.com/cosapp/cosapp/-/merge_requests/57), [#60](https://gitlab.com/cosapp/cosapp/-/merge_requests/60)).\n\n## 0.11.5 (2021-05-07)\n\n### New features\n\n* **New [binder container](https://mybinder.org/v2/gl/cosapp%2Fcosapp/master?urlpath=lab/tree/docs/tutorials)**,\n  allowing anyone to run interactively the tutorials used in the online documentation \n  (MR [#30](https://gitlab.com/cosapp/cosapp/-/merge_requests/30) and [#36](https://gitlab.com/cosapp/cosapp/-/merge_requests/36)).\n\n* **Deferred equations to set targets:**\n\n  New method `add_target`, defining a deferred equation on on a target variable (MR [#48](https://gitlab.com/cosapp/cosapp/-/merge_requests/48)).\n  In effect, `add_target` creates an equation whose right-hand side is evaluated dynamically prior to each execution of the nonlienar solver.\n\n  In the example below, the feature is illustrated in design mode. Outward `z` is a function of two independent variables `x` and `y`.\n  When design method `'target_z'` is activated, the actual value of `z`, set interactively, is used as a target value, with unknown `y`:\n  \n```python\nclass SystemWithTarget(System):\n    def setup(self):\n        self.add_inward('x', 1.0)\n        self.add_inward('y', 1.0)\n        self.add_outward('z', 1.0)\n\n        # Define design problem with a target on `z`\n        design = self.add_design_method('target_z')\n        design.add_unknown('y').add_target('z')\n\n    def compute(self):\n        self.z = self.x * self.y**2\n\ns = SystemWithTarget('s')\n\nsolver = s.add_driver(NonLinearSolver('solver', tol=1e-9))\n# Activate design method 'target_z': outward `z` becomes a target\nsolver.runner.design.extend(s.design_methods['target_z'])\n\ns.x = 0.5\ns.y = 0.5\ns.z = 2.0  # set target\ns.run_drivers()\nassert s.y == pytest.approx(2)  # solution of x * y**2 == 2\nassert s.z == pytest.approx(2)\n\ns.z = 4.0  # dynamically set new target\ns.run_drivers()\nassert s.y == pytest.approx(np.sqrt(8))  # solution of x * y**2 == 4\nassert s.z == pytest.approx(4)\n```\n  Targets can be also be declared in off-design mode, by calling `self.add_target(...)` in `System.setup`.\n\n### Documentation\n\n* Updated tutorials on `System`, `Driver`, and design methods (MR [#41](https://gitlab.com/cosapp/cosapp/-/merge_requests/41)).\n* Typo fix and improvements in time driver tutorial (MR [#33](https://gitlab.com/cosapp/cosapp/-/merge_requests/33))\n\n### Bug fixes, minor improvements and code quality\n\n* Report variable name in unit-related Connector warning message (MR [#32](https://gitlab.com/cosapp/cosapp/-/merge_requests/32)).\n* Automatically include field `time` in `DataFrame` recorders attached to a time driver (MR [#34](https://gitlab.com/cosapp/cosapp/-/merge_requests/34)).\n* Bug fix in `MonteCarlo` driver (MR [#37](https://gitlab.com/cosapp/cosapp/-/merge_requests/37)).\n* Replace `conda` by `mamba` in CI scripts (MR [#39](https://gitlab.com/cosapp/cosapp/-/merge_requests/39)).\n* Revamp markdown and JS rendering of systems and ports (MR [#40](https://gitlab.com/cosapp/cosapp/-/merge_requests/40) and [#43](https://gitlab.com/cosapp/cosapp/-/merge_requests/43), [#47](https://gitlab.com/cosapp/cosapp/-/merge_requests/47) and [#51](https://gitlab.com/cosapp/cosapp/-/merge_requests/51)).\n* Fix bug in `rate` type inference (MR [#44](https://gitlab.com/cosapp/cosapp/-/merge_requests/44)).\n* Other code quality improvement (MR [#35](https://gitlab.com/cosapp/cosapp/-/merge_requests/35), [#38](https://gitlab.com/cosapp/cosapp/-/merge_requests/38), [#42](https://gitlab.com/cosapp/cosapp/-/merge_requests/42), [#46](https://gitlab.com/cosapp/cosapp/-/merge_requests/46), [#50](https://gitlab.com/cosapp/cosapp/-/merge_requests/50), [#52](https://gitlab.com/cosapp/cosapp/-/merge_requests/52), [#53](https://gitlab.com/cosapp/cosapp/-/merge_requests/53)).\n\n## 0.11.4 (2021-03-08)\n\n### New features\n\n* Recorders:\n  It is now possible to add evaluable expressions in recorders (MR [#27](https://gitlab.com/cosapp/cosapp/-/merge_requests/27)):\n  \n```python\npoint = PointMass('point')\ndriver = point.add_driver(RungeKutta(order=3, time_interval=(0, 2), dt=0.01))\n\nrecorder = driver.add_recorder(recorders.DataFrameRecorder(\n    includes=['x', 'a', 'norm(v)']),  # norm(v) will be recorded in DataFrame\n    period=0.1,\n)\n```\n### Documentation\n\n* New tutorial on `SystemSurrogate` (MR [#15](https://gitlab.com/cosapp/cosapp/-/merge_requests/15)).\n\n### Bug fixes, minor improvements and code quality\n\n* Initialization bug in time simulations (MR [#23](https://gitlab.com/cosapp/cosapp/-/merge_requests/23)).\n* Bug in nonlinearity estimation in `NumericalSolver` (MR [#22](https://gitlab.com/cosapp/cosapp/-/merge_requests/22)).\n* Do not raise `ArithmeticError` when an unknown is declared several time (MR [#18](https://gitlab.com/cosapp/cosapp/-/merge_requests/18)).\n* Suppress deprecation warnings raised by `numpy` (MR [#20](https://gitlab.com/cosapp/cosapp/-/merge_requests/20) and [#24](https://gitlab.com/cosapp/cosapp/-/merge_requests/24)).\n* Suppress undue warning raised by `numpy` in `NonLinearSolver` (MR [#19](https://gitlab.com/cosapp/cosapp/-/merge_requests/19)).\n* Fix incompatibility between `pandas` and `xlrd` (MR [#21](https://gitlab.com/cosapp/cosapp/-/merge_requests/21)).\n* Other code quality improvement (MR [#16](https://gitlab.com/cosapp/cosapp/-/merge_requests/16), [#17](https://gitlab.com/cosapp/cosapp/-/merge_requests/17), [#26](https://gitlab.com/cosapp/cosapp/-/merge_requests/26), [#27](https://gitlab.com/cosapp/cosapp/-/merge_requests/27)).\n\n## 0.11.3 (2020-12-16)\n\n### New features\n\n* Surrogate models:\n  It is now possible to create a surrogate model at any system level with new method `System.make_surrogate` (MR [#3](https://gitlab.com/cosapp/cosapp/-/merge_requests/3) and [#12](https://gitlab.com/cosapp/cosapp/-/merge_requests/12)):\n  \n```python\nplane = Aeroplane('plane')  # system with subsystems engine1 and engine2\n\n# Say engine systems have one input parameter `fuel_rate`\n# and possibly several outputs, and many sub-systems\n\n# Create training schedule for input data\ndoe = pandas.DataFrame(\n    # loads of input data\n    columns=['fuel_rate', 'fan.diameter', ..]  # input names\n)\nplane.engine1.make_surrogate(doe)  # generates output data and train model\n\nplane.run_once()  # executes the surrogate model of `engine1` instead of original compute()\n\n# dump model to file\nplane.engine1.dump_surrogate('engine.bin')\n# load model into `engine2`:\nplane.engine2.load_surrogate('engine.bin')\n\n# deactivate surrogate model on demand\nplane.engine1.active_surrogate = plane.engine2.active_surrogate = False\n```\n\n### Bug fixes, minor improvements and code quality\n\n* Add several US-common unit conversions (MR [#2](https://gitlab.com/cosapp/cosapp/-/merge_requests/2)).\n* New method to export cosapp system structure into a dictionary (MR [#5](https://gitlab.com/cosapp/cosapp/-/merge_requests/5))\n* Make recorders capture port and system properties (MR [#8](https://gitlab.com/cosapp/cosapp/-/merge_requests/8)).\n* Fix Module/System naming bug: *'inwards' and 'outwards' are allowed as Module/System names* (MR [#9](https://gitlab.com/cosapp/cosapp/-/merge_requests/9)).\n* Broad code quality improvement (MR [#11](https://gitlab.com/cosapp/cosapp/-/merge_requests/11)).\n\n  * Replace `typing.NoReturn` by `None` when appropriate.\n  * Rewording pass, typo and error fixes in tutorial notebooks.\n  * Suppress a `DeprecationWarning` raised by `numpy` in class `Variable`.\n  * Reformat many strings as Python f-strings, for clarity.\n  * Symplify many occurrences of `str.join()` for just two elements.\n\nGlobal rewording of tutorial notebooks, including a few error fixes.\n\n## 0.11.2 (2020-09-28)\n\nFirst open-source version.\nNo major code change; mostly updates of license files, URLs in docs, and CI scripts.\n\n## 0.11.1 (2020-07-22)\n\n### Features\n\n* Add the possibility to set boundary condition of transient simulation from interpolate profile.\n* Add the possibility to prescribe a maximum step for transient variables.\n\n### Bugs and code quality\n\n* Bug fix in `RunOnce` driver, preventing undue call to `run_once` method.\n* Bug fix in AssignString: force copy for numpy arrays.\n* New tutorial for advanced features of time simulations in CosApp.\n\n## 0.11.0 (2020-05-12)\n\n### Features\n\n* Improve documentation at various places, add documentation about the cosapp packages structure and sequence diagram for transient simulation.\n* Add a advanced logger feature for CoSApp simulations.\n* Update FMU export to PythonFMU 0.6.0\n* New method `System.add_property` allowing users to create read-only properties.\n\n### Bugs and code quality\n\n* Suppress deprecation warnings raised by external dependencies. \n* Fix bug in AssignString with arrays, `AssignString` of the kind `'x = [0, 1, 2]'` won't change variable `x` into an array of integers,  if `x` is declared as an array of floats.\n* Fix `TimeStackUnknown` not able to stack transient variables defined on a children System or with partially pulled transient variable.\n* Fix the bug related to the initialization of `rate` attributes in systems.\n\n## 0.10.2 (2020-04-21)\n\n### Features\n\n* [BETA] Export CoSApp System as FMU\n\n### Bugs and code quality\n\n* Apply Broyden correction on Jacobian matrix for iteration without Jacobian update\n* Support varying time step\n* Fix time not being set before `setup_run` are called.\n* Fix reference for residues in `IterativeConnector` (it equals 1. now)\n* Drop pyhamcrest for pytest\n\n## 0.10.1 (2020-01-15)\n\n### Features\n\n* Time varying boundary conditions are now possible:\n\n```python\nsystem = MySystem('something')  # system with transient variables x and v\ndriver = system.add_driver(RungeKutta(time_interval=(0, 2), dt=0.01, order=3))\n\ndriver.set_scenario(\n    init = {'x': 0.5, 'v': 0},  # initial conditions\n    values =\n    {\n        'omega': 0.7,\n        'F_ext': '0.6 * cos(omega * t)'  # explicit time-dependency\n    }\n)\n```\n\n### Bugs and code quality\n\n* Fix various bug on the transient simulation front\n* Correct implementation of step limitation in the Newton-Raphson solver\n* Using a logger at `DEBUG` level will now display the call stack through the systems and drivers\n* Rework of the Python evaluable string to be more efficient\n\n## 0.10.0 (2019-10-23)\n\n* Introduce continuous time simulations with dedicated time drivers (see `TimeDriver` notebook in tutorials).\n* Suppress notion of (un)freeze; all variables are considered as known, unless explicitly declared as unknowns.\n* Drivers no longer use ports.\n* Connectors are now stored by parent system.\n* Migrate to pytest.\n\n### API Changes\n\n* Ports:\n\n  * `add_variable(\"x\", units=\"m\", types=Number)` => `add_variable(\"x\", unit=\"m\", dtype=Number)`\n  * `freeze` => removed\n  * `unfreeze` => replaced by `add_unknown` in Systems and Drivers\n  * `connect_to` => replaced by `connect` at system level\n  \n* Systems:\n\n  * `time_ref` is no longer an argument of method `compute`:\n  \n    `def compute(self, time_ref):` => `def compute(self):`\n       \n  * Create a new connection between `a.in1` and `b.out`:\n  \n    `self.a.in1.connect_to(self.b.out)` => `self.connect(self.a.in1, self.b.out)`\n       \n  * `add_residues` => `add_equation`\n  * `set_numerical_default` => Pass keyword to `add_unknown`\n  * `add_inward(\"x\", units=\"m\", types=Number)` => `add_inward(\"x\", unit=\"m\", dtype=Number)`\n  * `add_outward(\"x\", units=\"m\", types=Number)` => `add_outward(\"x\", unit=\"m\", dtype=Number)`\n  \n* Drivers:\n\n  * `add_unknowns(maximal_absolute_step, maximal_relative_step, low_bound, high_bound)` => `add_unknown(max_abs_step, max_rel_step, lower_bound, upper_bound)`\n  * `add_equations` => `add_equation`\n  * Equations are now represented by a unique string, instead of two strings (left-hand-side, right-hand-side):\n  \n    `add_equations(\"a\", \"b\")` => `add_equation(\"a == b\")`  \n    \n    `add_equations([(\"x\", \"2 * y + 1\"), (\"a\", \"b\")])` => `add_equation([\"x == 2 * y + 1\", \"a == b\"])`  \n        \n  * For `NonLinearSolver`:\n  \n    `fatol` and `xtol` => `tol`  \n    \n    `maxiter` => `max_iter`  \n        \n  * For `Optimizer`:\n  \n    `ftol` => `tol`\n    \n    `maxiter` => `max_iter`\n\n## 0.9.6 (2019-10-10)\n\n* More correction for VISjs viewer and System HTML representation\n\n## 0.9.5 (2019-09-25)\n\n* Correct D3 & VISjs Viewers\n\n## 0.9.4 (2019-09-25)\n\n* Introduce an optional environment variable `COSAPP_CONFIG_DIR`\n\n## 0.9.3 (2019-07-25)\n\n### API Changes\n\n* MonteCarlo:\n\n  * `Montecarlo` => `MonteCarlo`\n  * `Montecarlo.add_input_vars` => `MonteCarlo.add_random_variable`\n  * `Montecarlo.add_response_vars` => `MonteCarlo.add_response`\n\n* MonteCarlo has been improved by using Sobol random generator\n* Viewers code on `System` is moved in a subpackage of `cosapp.tools`\n* Residue reference is now calculated only once\n* Various bug fix\n\n## 0.9.2 (2019-07-01)\n* In nonlinear solver, store LU factorization of the Jacobian matrix, rather than its inverse.\n* Minor refactoring of the core source code, with no API changes\n\n## 0.9.1 (2019-04-23)\n\n* Create `Variable` class to manage variable attributes\n* `watchdog` is now optional\n* Configuration is now inside a folder `$HOME/.cosapp.d`\n* API changes:\n  - `get_latest_solution` => `save_solution`\n  - `load_solver_solution` => `load_solution`\n* Various bug fix\n\n## 0.9.0 (2019-03-04)\n\nThis release introduces lots of API changes:\n\n* Core ports and unit are available in `cosapp.ports`\n* Core systems are available in `cosapp.systems`\n* Core drivers are available in `cosapp.drivers`\n* Core recorders are available in `cosapp.recorders`\n* Core tools are available in `cosapp.tools`\n* Core notebook tools are available in `cosapp.notebook` (! this is now a separated package)\n* `data` have been renamed in `inwards` and `add_data` in `add_inward`\n* `locals` have been renamed in `outwards` and `add_locals` in `add_outward`\n* `BaseRecorder.record_iteration` renamed in `BaseRecorder.record_state`\n\n- Huge code refractoring: cosapp is now a [Python namespace](https://packaging.python.org/guides/packaging-namespace-packages).\n- `cosapp.notebook` has been moved to an independent package `cosapp_notebook`. But it is still accessible from `cosapp.notebook`.\n- Introduce *Signal* / *Slot* pattern to connect to internal event (implementation from [signalslot](https://github.com/Numergy/signalslot), included in `cosapp.core.signal`)\n    * `Module.setup_ran`: Signal emitted after the `call_setup_run` execution\n    * `Module.computed`: Signal emitted after the full `compute` stack (i.e.: `_postcompute`)\n    * `Module.clean_ran`: Signal emitted after the `call_clean_run` execution\n    * `BaseRecorder.state_recorded`: Signale emitted after the `record_state` execution\n\n## 0.8.0 (2018-10-26)\n\n- Add Jacobian partial matrix update\n- Add numerical features to variables to ease convergence control\n- Add monitoring of solver residues\n- Add restoration of solver result for initialization\n- Rework residues and unknowns handling (remove virtual port and pulling port)\n- Rework optimizer to be more homogeneous with non-linear solver\n- Improve linear Monte Carlo computation time\n- Improve data viewer for non-linear solver\n- Create viewer for Monte Carlo\n- Add dropdown widget for enum variables\n\n## 0.7.0 (2018-09-17)\n\n- Add helper functions to present solver evolutions\n- Add new d3 visualization of systems\n\n## 0.6.0 (2018-08-14)\n\n- Implement clean-dirty policy\n- Restore compatibility with Python 3.4\n- Display influence matrix\n\n## 0.5.0 (2018-07-20)\n\n- Simplify drivers structure, all actions for a case are supported by a single class `RunSingleCase`\n- Add support for vector variables; they can be partially (un)frozen and are handled correctly by the solver.\n- Add `MonteCarlo` driver\n- Add recording data capability\n\n## 0.4.0 (2018-06-15)\n\n- `System` and `Driver` have now a common ancestor `Module` => `Driver` variables are now stored as data or locals\n- Add visualization of `System` connections based on N2 graph (syntax: `cosapp.viewmodel(mySystem)`)\n\n## 0.3.0 (2018-04-05)\n\n**API changes:** `System.add_driver` and `Driver.add_child` take now an instance of `Driver`\n\n- Add external code caller System\n- Add validation range attributes on variables\n- Add variable visibility\n- Add metamodel training and DoE generator\n- Add helper function to list inputs and outputs variables of a `System`\n\n## 0.2.0 (2018-03-01)\n\n* Stabilization of the user API\n\n## 0.1.0 (2018-01-02)\n\n* First release.\n",
    "bugtrack_url": null,
    "license": "Apache-2.0",
    "summary": "CoSApp, the Collaborative System Approach.",
    "version": "0.16.0",
    "project_urls": {
        "Homepage": "https://cosapp.readthedocs.io"
    },
    "split_keywords": [
        "cosapp",
        " system simulation",
        " system design"
    ],
    "urls": [
        {
            "comment_text": "",
            "digests": {
                "blake2b_256": "59d7c101f147958b1019c769f3ca2cac053a7f1830056323b090a5796a1c30f4",
                "md5": "0a87022b246a4631322f03ff7b6b5d81",
                "sha256": "470378b2b4d6bd5c238737f23ba0851fdd9b831ce51265e60fbe5d074e6a9105"
            },
            "downloads": -1,
            "filename": "cosapp-0.16.0-py3-none-any.whl",
            "has_sig": false,
            "md5_digest": "0a87022b246a4631322f03ff7b6b5d81",
            "packagetype": "bdist_wheel",
            "python_version": "py3",
            "requires_python": ">=3.8",
            "size": 1046725,
            "upload_time": "2024-04-18T14:27:48",
            "upload_time_iso_8601": "2024-04-18T14:27:48.001718Z",
            "url": "https://files.pythonhosted.org/packages/59/d7/c101f147958b1019c769f3ca2cac053a7f1830056323b090a5796a1c30f4/cosapp-0.16.0-py3-none-any.whl",
            "yanked": false,
            "yanked_reason": null
        },
        {
            "comment_text": "",
            "digests": {
                "blake2b_256": "ef5a571d1a48a25f49bf4ab2d1b2228a7237cd3b881a0e9f4191948deec076df",
                "md5": "62bbe8b10e47f514e42b370db8ad3f35",
                "sha256": "2f849efc92afc4872a73b5f9226daccaedd733e2f2a5bf473d6855a906f100de"
            },
            "downloads": -1,
            "filename": "cosapp-0.16.0.tar.gz",
            "has_sig": false,
            "md5_digest": "62bbe8b10e47f514e42b370db8ad3f35",
            "packagetype": "sdist",
            "python_version": "source",
            "requires_python": ">=3.8",
            "size": 3294261,
            "upload_time": "2024-04-18T14:27:45",
            "upload_time_iso_8601": "2024-04-18T14:27:45.227347Z",
            "url": "https://files.pythonhosted.org/packages/ef/5a/571d1a48a25f49bf4ab2d1b2228a7237cd3b881a0e9f4191948deec076df/cosapp-0.16.0.tar.gz",
            "yanked": false,
            "yanked_reason": null
        }
    ],
    "upload_time": "2024-04-18 14:27:45",
    "github": false,
    "gitlab": false,
    "bitbucket": false,
    "codeberg": false,
    "lcname": "cosapp"
}