Technosphere flows

To retrieve the technosphere matrix, use the techIndex method. It will return an iterator of TechFlows: TechIndex, which maps symmetrically the rows (products or wastes) and columns (process, product systems, ...) of the technology matrix.

class TechFlow:
  def provider(): # () -> RootDescriptor
  def flow(): # () -> FlowDescriptor

NOTE: More information about RootDescriptor and FlowDescriptor can be found in the The advanced data model chapter.

You can create a TechFlow object by calling the TechFlow.of method. When using the method on a process, it will return a tech-flow from the given process with the quantitative reference. When using the method on a product system, it will return a tech-flow from the given product system with the reference of that system.

tech_flow = TechFlow.of(provider, flow)  # (Process, Flow) -> TechFlow
tech_flow = TechFlow.of(process)  # (Process) -> TechFlow
tech_flow = TechFlow.of(system)  # (ProductSystem) -> TechFlow

tech_index = result.techIndex()
for tech_flow in tech_index:
    print(
        "Provider: %s\nFlow: %s\n" % (tech_flow.provider().name, tech_flow.flow().name)
    )

Total requirements

To get the total requirements of a technosphere flow, we use the getTotalRequirementsOf method. It will return the total amount of the flow required by the corresponding provider.

tech_index = result.techIndex()
for tech_flow in tech_index:
    print(
        "The flow %s in %s requires a total amount of %s\n"
        % (
            tech_flow.flow().name,
            tech_flow.provider().name,
            result.getTotalRequirementsOf(tech_flow),
        )
    )

Scaled technosphere flows

The scaled technosphere flows of a process are the scaled inputs and outputs of the linked product and waste flows of that process related to the final demand of the product system. They can be obtained with the getScaledTechFlowsOf method. It will return a list of TechFlowValue, which is a record:

class TechFlowValue:
    def techFlow(): # () -> TechFlow
    def value(): # () -> float

For example, to get the scaled technosphere flows amount of the first process in the technosphere matrix:

tech_flow = TechFlow.of(system)
scaled_tech_flows = result.getScaledTechFlowsOf(tech_flow)
for tech_flow_value in scaled_tech_flows:
    print(
        "The scaled amount of %s is %s."
        % (tech_flow_value.techFlow().flow().name, tech_flow_value.value())
    )

Unscaled technosphere flows

The unscaled requirements of a process are the direct requirements of the process related to the quantitative reference of that process without applying a scaling factor. For example, the unscaled amount of the flows of the last column:

scaled_tech_flows = result.getUnscaledTechFlowsOf(tech_flow)
for tech_flow_value in scaled_tech_flows:
    print(
        "The scaled amount of %s is %s."
        % (tech_flow_value.techFlow().flow().name, tech_flow_value.value())
    )

For more...

For more specific methods, please refer to the LcaResult class.