bw2analyzer.utils#

Functions#

contribution_for_all_datasets_one_method(database, method)

Calculate contribution analysis (for technosphere processes) for all inventory datasets in one database for one LCIA method.

infinite_alphabet()

Return generator with values a-z, then aa-az, ba-bz, then aaa-aaz, aba-abz, etc.

print_recursive_calculation(activity, lcia_method[, ...])

Traverse a supply chain graph, and calculate the LCA scores of each component. Prints the result with the format:

print_recursive_supply_chain(activity[, amount, ...])

Traverse a supply chain graph, and prints the inputs of each component.

recursive_calculation_to_object(activity, lcia_method)

Traverse a supply chain graph, and calculate the LCA scores of each component. Adds a dictionary to result_list of the form:

Module Contents#

bw2analyzer.utils.contribution_for_all_datasets_one_method(database, method, progress=True)[source]#

Calculate contribution analysis (for technosphere processes) for all inventory datasets in one database for one LCIA method.

Parameters:

  • *database* (str) – Name of database

  • *method* (tuple) – Method tuple

Returns:

NumPy array of relative contributions. Each column sums to one. Lookup dictionary, dataset keys to row/column indices

bw2analyzer.utils.infinite_alphabet()[source]#

Return generator with values a-z, then aa-az, ba-bz, then aaa-aaz, aba-abz, etc.

bw2analyzer.utils.print_recursive_calculation(activity, lcia_method, amount=1, max_level=3, cutoff=0.01, string_length=130, file_obj=None, tab_character='  ', use_matrix_values=False, _lca_obj=None, _total_score=None, __level=0, __first=True)[source]#

Traverse a supply chain graph, and calculate the LCA scores of each component. Prints the result with the format:

{tab_character * level }{fraction of total score} ({absolute LCA score for this input} | {amount of input}) {input activity}

Parameters:

  • activity – Activity. The starting point of the supply chain graph.

  • lcia_method – tuple. LCIA method to use when traversing supply chain graph.

  • amount – int. Amount of activity to assess.

  • max_level – int. Maximum depth to traverse.

  • cutoff – float. Fraction of total score to use as cutoff when deciding whether to traverse deeper.

  • string_length – int. Maximum length of printed string.

  • file_obj – File-like object (supports .write), optional. Output will be written to this object if provided.

  • tab_character – str. Character to use to indicate indentation.

  • use_matrix_values – bool. Take exchange values from the matrix instead of the exchange instance amount. Useful for Monte Carlo, but can be incorrect if there is more than one exchange from the same pair of nodes.

Normally internal args:

_lca_obj: LCA. Can give an instance of the LCA class (e.g. when doing regionalized or Monte Carlo LCA) _total_score: float. Needed if specifying _lca_obj.

Internal args (used during recursion, do not touch);

__level: int. __first: bool.

Returns:

Nothing. Prints to sys.stdout or file_obj

bw2analyzer.utils.print_recursive_supply_chain(activity, amount=1, max_level=2, cutoff=0, string_length=130, file_obj=None, tab_character='  ', __level=0)[source]#

Traverse a supply chain graph, and prints the inputs of each component.

This function is only for exploration; use bw2calc.GraphTraversal for a better performing function.

The results displayed here can also be incorrect if

Parameters:

  • activity – Activity. The starting point of the supply chain graph.

  • amount – int. Supply chain inputs will be scaled to this value.

  • max_level – int. Max depth to search for.

  • cutoff – float. Inputs with amounts less than amount * cutoff will not be printed or traversed further.

  • string_length – int. Maximum length of each line.

  • file_obj – File-like object (supports .write), optional. Output will be written to this object if provided.

  • tab_character – str. Character to use to indicate indentation.

  • __level – int. Current level of the calculation. Only used internally, do not touch.

Returns:

Nothing. Prints to stdout or file_obj

bw2analyzer.utils.recursive_calculation_to_object(activity, lcia_method, amount=1, max_level=3, cutoff=0.01, as_dataframe=False, root_label='root', use_matrix_values=False, _lca_obj=None, _total_score=None, __result_list=None, __level=0, __label='', __parent=None)[source]#

Traverse a supply chain graph, and calculate the LCA scores of each component. Adds a dictionary to result_list of the form:

{

‘label’: Label of this branch. Starts with nothing, then A, AA, AB, AAA, AAB, etc. ‘score’: Absolute score of this activity ‘fraction’: Fraction of total score of this activity ‘amount’: Input amount of the reference product of this activity ‘name’: Name of this activity ‘key’: Activity key ‘root_label’: Starting label of root element for recursion.

}

Parameters:

  • activity – Activity. The starting point of the supply chain graph.

  • lcia_method – tuple. LCIA method to use when traversing supply chain graph.

  • amount – int. Amount of activity to assess.

  • max_level – int. Maximum depth to traverse.

  • cutoff – float. Fraction of total score to use as cutoff when deciding whether to traverse deeper.

  • as_dataframe – Return results as a list (default) or a pandas DataFrame

  • use_matrix_values – bool. Take exchange values from the matrix instead of the exchange instance amount. Useful for Monte Carlo, but can be incorrect if there is more than one exchange from the same pair of nodes.

Internal args (used during recursion, do not touch):

__result_list: list. __level: int. __label: str. __parent: str.

Returns:

List of dicts