But === Define a mesh using macro elements. This command allows you to define a new mesh based on static or dynamic macroelements. This new mesh (containing only the geometric supports of the macro-elements) can then be "assembled" to another mesh (containing for example "classic" meshes) using the command ASSE_MAILLAGE [:external:ref:`U4.23.03 `] and the option specific to substructuring. Produces a mesh-like data structure.