Calculation and results
When starting a calculation, it is first scheduled in a calculation queue. This
is because multiple calculations could be started at the same time and
calculations may need to wait for other calculations first to be finished. Thus,
a calculation directly returns a
ResultState
object with a unique identifier. With this identifier, the state of the
calculation can be retrieved from the server. It is then also the ID of the
corresponding result when the calculation is finished. When a result is not
needed anymore, the dispose method should be called so that the allocated
resources of the result can be released.
The idea of the result interface is not to provide some ready-to-use charts and tables but to provide all possible building blocks with which such higher level result views can be created (charts, tables, upstream trees, Sankey diagrams). Thus, the result interface has many methods that often look quite similar but they have their purpose for efficiently creating higher level result views.
Result elements
Depending on the calculation setup and the calculated model, results can be retrieved for different elements, these are:
- Technosphere flows,
tech-flows: the product and waste flows of the product system with their corresponding providers. - Intervention flows,
envi-flows: typically elementary flows but also unconnected product or waste inputs or outputs of the processes in the system. These flows cross the boundary to the environment of the system and form the inventory result of the system. In case of a regionalized calculation, an intervention flow is a pair of flow and location. - Impact categories,
impact-categories: the impact categories of the impact assessment method selected in the calculation setup. - costs: life cycle costs
Technosphere flows are always present. All other result elements are only available if the calculated model provides these elements and/or if the corresponding options are set in the calculation setup.
Mathematical relations
Where possible, a short formula for calculating a respective result is provided in the following documentation of the respective functions. These formulas are based on standard matrix algebra for LCA computations. However, this does not mean that a respective result is calculated by exactly using this formula.