Files changed (11)
+This package provides the calculation engine for the `Brightway2 life cycle assessment framework <http://brightwaylca.org>`_. `Online documentation <http://bw2calc.readthedocs.org>`_ is available, and the source code is hosted on `Bitucket <https://bitbucket.org/cmutel/brightway2-calc>`_.
The emphasis here has been on speed of solving the linear systems, for normal LCA calculations, graph traversal, or Monte Carlo uncertainty analysis.
The Monte Carlo LCA class can do about 30 iterations a second (on a 2011 MacBook Pro). Instead of doing LU factorization, it uses an initial guess and the conjugant gradient squared algorithm.
The multiprocessing Monte Carlo class (ParallelMonteCarlo) can do about 100 iterations a second, using 7 virtual cores. The MultiMonteCarlo class, which does Monte Carlo for many processes (and hence can re-use the factorized technosphere matrix), can do about 500 iterations a second, using 7 virtual cores. Both these algorithms perform best when the initial setup for each worker job is minimized, e.g. by dispatching big chunks.
+ """The default graph traversal includes links which might be of small magnitude. This function cuts links that have small cumulative impact."""
+This class takes nodes and edges, and removes nodes to edges with low individual scores and reroutes the edges.
We do this by first retrieving the regionalized characterization factors for each location where characterization factors are avaiable. The intermediate data structure ``regionalized_dict`` has the following structure:
We then use the ``np.unique`` function to retrieve all technosphere processes, and an index into ``self.tech_params`` for each of them. We can then use this index to get a location for each technosphere process.
- The characterization matrix has dimensions (number of biosphere flows, number of technosphere flows). For each column, we lookup the location code, and then retrieve the cf amounts and row indices from the ``regionalized_dict``. We can then build the ``characterization_matrix``.
+ The characterization matrix has dimensions (number of biosphere flows, number of technosphere flows). For each column, we lookup the location code, and then retrieve the cf amounts and row indices from the ``regionalized_dict``. We can then build the ``characterization_matrix``.
.. note:: There is a lot of duplicate data in ``characterization_matrix``, as characterization factors are provided for each technosphere process, regardless of whether that technosphere location has been seen already.
+This is the technical documentation for Brightway2-calc, part of the `Brightway2 <http://brightwaylca.org>`_ life cycle assessment calculation framework. The following online resources are available:
+To run the tests, install `nose <https://nose.readthedocs.org/en/latest/>`_, and run ``nosetests``.
+Install `sphinx <http://sphinx.pocoo.org/>`_, and then change to the ``docs`` directory, and run ``make html`` (or ``make.bat html`` in Windows).