compas.numerical.dr_numpy(vertices, edges, fixed, loads, qpre, fpre=None, lpre=None, linit=None, E=None, radius=None, callback=None, callback_args=None, **kwargs)[source]

Implementation of the dynamic relaxation method for form findong and analysis of articulated networks of axial-force members.

  • vertices (list) – XYZ coordinates of the vertices.

  • edges (list) – Connectivity of the vertices.

  • fixed (list) – Indices of the fixed vertices.

  • loads (list) – XYZ components of the loads on the vertices.

  • qpre (list) – Prescribed force densities in the edges.

  • fpre (list, optional) – Prescribed forces in the edges.

  • lpre (list, optinonal) – Prescribed lengths of the edges.

  • linit (list, optional) – Initial length of the edges.

  • E (list, optional) – Stiffness of the edges.

  • radius (list, optional) – Radius of the edges.

  • callback (callable, optional) – User-defined function that is called at every iteration.

  • callback_args (tuple, optional) – Additional arguments passed to the callback.


  • xyz (array) – XYZ coordinates of the equilibrium geometry.

  • q (array) – Force densities in the edges.

  • f (array) – Forces in the edges.

  • l (array) – Lengths of the edges

  • r (array) – Residual forces.


For more info, see 1.



De Laet L., Veenendaal D., Van Mele T., Mollaert M. and Block P., Bending incorporated: designing tension structures by integrating bending-active elements, Proceedings of Tensinet Symposium 2013,Istanbul, Turkey, 2013.