(by Tary)
Swallow can be used to define and assemble structural analysis models, and  quickly import the models into Etabs software for calculation.
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Swallow can be used to define structural attributes such as story height, section attributes, loads and node constraints, and bind these attributes to the geometric model in Grasshopper and then assemble them into a structural analysis model, and then use Etabs' OAPI or Sap2000' OAPI interface to import the model into Etabs or Sap2000 for Calculation.

The plugin can  be installed in Rhino 6 (both 64 and 32 bit platforms) SR19 or Later.