bw2io 0.5.10

This package provides tools for the import, export, and management of inventory databases and impact assessment methods. It is part of the Brightway2 LCA framework. Online documentation is available, and the source code is hosted on Bitbucket.

In contrast with previous IO functionality in Brightway2, brightway2-io uses an iterative approach to importing and linking data. First, data is extracted into a common format. Next, a series of strategies is employed to uniquely identify each dataset and link datasets internally and to the biosphere. Following internal linking, linking to other background datasets can be performed. Finally, database data is written to disk.

This approach offers a number of benefits that help mitigate some of the serious problems in existing inventory data formats: the number of unlinked exchanges can be easily seen, linking strategies can be iteratively applied, and intermediate results can be saved.

Here is a typical usage:

In [1]: from bw2io import *

In [2]: so = SingleOutputEcospold2Importer("/path/to/ecoinvent/3.1/cutoff/datasets", "ecoinvent 3.1 cutoff")
11301/11301 (100%) |||||||||||||||||||||||||||||||||||||||||||||||||||||||||| Time: 0:01:56
Converting to unicode
Extracted 11301 datasets in 262.63 seconds

In [3]: so.apply_strategies()
Applying strategy: remove_zero_amount_coproducts
Applying strategy: remove_zero_amount_inputs_with_no_activity
Applying strategy: es2_assign_only_product_with_amount_as_reference_product
Applying strategy: assign_single_product_as_activity
Applying strategy: create_composite_code
Applying strategy: link_biosphere_by_flow_uuid
Applying strategy: link_internal_technosphere_by_composite_code
Applying strategy: delete_exchanges_missing_activity
Applying strategy: delete_ghost_exchanges
Applying strategy: mark_unlinked_exchanges

In [4]: so.statistics()
11301 datasets
521712 exchanges
0 unlinked exchanges
Out[4]: (11301, 521712, 0)

In [5]: so.write_database()

Note that brightway2-io can’t magically make problems in databases go away.