Base Model#

class pybamm.BaseModel(name='Unnamed model')[source]#

Base model class for other models to extend.

name#

A string giving the name of the model.

Type:

str

submodels#

A dictionary of submodels that the model is composed of.

Type:

dict

boundary_conditions#

A dictionary that maps expressions (variables) to expressions that represent the boundary conditions.

Type:

dict

variables#

A dictionary that maps strings to expressions that represent the useful variables.

Type:

dict

use_jacobian#

Whether to use the Jacobian when solving the model (default is True).

Type:

bool

convert_to_format#

Whether to convert the expression trees representing the rhs and algebraic equations, Jacobain (if using) and events into a different format:

  • None: keep PyBaMM expression tree structure.

  • “python”: convert into pure python code that will calculate the result of calling evaluate(t, y) on the given expression treeself.

  • “casadi”: convert into CasADi expression tree, which then uses CasADi’s algorithm to calculate the Jacobian.

  • “jax”: convert into JAX expression tree

Default is “casadi”.

Type:

str

check_algebraic_equations(post_discretisation)[source]#

Check that the algebraic equations are well-posed. After discretisation, there must be at least one StateVector in each algebraic equation.

check_discretised_or_discretise_inplace_if_0D()[source]#

Discretise model if it isn’t already discretised This only works with purely 0D models, as otherwise the mesh and spatial method should be specified by the user

check_ics_bcs()[source]#

Check that the initial and boundary conditions are well-posed.

check_no_repeated_keys()[source]#

Check that no equation keys are repeated.

check_well_determined(post_discretisation)[source]#

Check that the model is not under- or over-determined.

check_well_posedness(post_discretisation=False)[source]#

Check that the model is well-posed by executing the following tests: - Model is not over- or underdetermined, by comparing keys and equations in rhs and algebraic. Overdetermined if more equations than variables, underdetermined if more variables than equations. - There is an initial condition in self.initial_conditions for each variable/equation pair in self.rhs - There are appropriate boundary conditions in self.boundary_conditions for each variable/equation pair in self.rhs and self.algebraic

Parameters:

post_discretisation (boolean) – A flag indicating tests to be skipped after discretisation

property default_solver#

Return default solver based on whether model is ODE/DAE or algebraic

classmethod deserialise(properties: dict)[source]#

Create a model instance from a serialised object.

export_casadi_objects(variable_names, input_parameter_order=None)[source]#

Export the constituent parts of the model (rhs, algebraic, initial conditions, etc) as casadi objects.

Parameters:
  • variable_names (list) – Variables to be exported alongside the model structure

  • input_parameter_order (list, optional) – Order in which the input parameters should be stacked. If input_parameter_order=None and len(self.input_parameters) > 1, a ValueError is raised (this helps to avoid accidentally using the wrong order)

Returns:

casadi_dict – Dictionary of {str: casadi object} pairs representing the model in casadi format

Return type:

dict

generate(filename, variable_names, input_parameter_order=None, cg_options=None)[source]#

Generate the model in C, using CasADi.

Parameters:
  • filename (str) – Name of the file to which to save the code

  • variable_names (list) – Variables to be exported alongside the model structure

  • input_parameter_order (list, optional) – Order in which the input parameters should be stacked. If input_parameter_order=None and len(self.input_parameters) > 1, a ValueError is raised (this helps to avoid accidentally using the wrong order)

  • cg_options (dict) – Options to pass to the code generator. See https://web.casadi.org/docs/#generating-c-code

get_parameter_info(by_submodel=False)[source]#

Extracts the parameter information and returns it as a dictionary. To get a list of all parameter-like objects without extra information, use model.parameters.

Parameters:

by_submodel (bool, optional) – Whether to return the parameter info sub-model wise or not (default False)

info(symbol_name)[source]#

Provides helpful summary information for a symbol.

Parameters:

parameter_name (str)

property input_parameters#

Returns all the input parameters in the model

latexify(filename=None, newline=True, output_variables=None)[source]#

Converts all model equations in latex.

Parameters:
  • filename (str (optional)) – Accepted file formats - any image format, pdf and tex Default is None, When None returns all model equations in latex If not None, returns all model equations in given file format.

  • newline (bool (optional)) – Default is True, If True, returns every equation in a new line. If False, returns the list of all the equations.

  • model (Load)

  • pybamm.lithium_ion.SPM() (>>> model =)

  • png (This will returns all model equations in)

  • doctest (>>> model.latexify(newline=False) #)

  • latex (This will return all the model equations in)

  • doctest

  • equations (This will return first five model)

  • doctest

  • equations

  • model.latexify(newline=False)[1 (>>>)

new_copy()[source]#

Creates a copy of the model, explicitly copying all the mutable attributes to avoid issues with shared objects.

property parameters#

Returns all the parameters in the model

print_parameter_info(by_submodel=False)[source]#

Print parameter information in a formatted table from a dictionary of parameters

Parameters:

by_submodel (bool, optional) – Whether to print the parameter info sub-model wise or not (default False)

process_parameters_and_discretise(symbol, parameter_values, disc)[source]#

Process parameters and discretise a symbol using supplied parameter values and discretisation. Note: care should be taken if using spatial operators on dimensional symbols. Operators in pybamm are written in non-dimensional form, so may need to be scaled by the appropriate length scale. It is recommended to use this method on non-dimensional symbols.

Parameters:
Returns:

Processed symbol

Return type:

pybamm.Symbol

save_model(filename=None, mesh=None, variables=None)[source]#

Write out a discretised model to a JSON file

Parameters:
  • filename (str, optional)

  • provided (The desired name of the JSON file. If no name is)

  • created (one will be)

  • name (based on the model)

  • datetime. (and the current)

set_initial_conditions_from(solution, inplace=True, return_type='model')[source]#

Update initial conditions with the final states from a Solution object or from a dictionary. This assumes that, for each variable in self.initial_conditions, there is a corresponding variable in the solution with the same name and size.

Parameters:
  • solution (pybamm.Solution, or dict) – The solution to use to initialize the model

  • inplace (bool, optional) – Whether to modify the model inplace or create a new model (default True)

  • return_type (str, optional) – Whether to return the model (default) or initial conditions (“ics”)

update(*submodels)[source]#

Update model to add new physics from submodels

Parameters:

submodel (iterable of pybamm.BaseModel) – The submodels from which to create new model

property variables_and_events#

Returns variables and events in a single dictionary