Maxwell impedance BC can now be assigned to faces as well, improved docstring (#4229)

* impedance BC can now be assigned to faces as well, improved docstring

* updated assign_impedance unit test

---------

Co-authored-by: Samuel Lopez <[email protected]>

Author: IreneWoyna

_unittest/test_28_Maxwell3D.py

@@ -639,6 +639,9 @@ def test_39_assign_current_density_terminal(self):
 
     def test_40_assign_impedance(self):
         impedance_box = self.aedtapp.modeler.create_box([-50, -50, -50], [294, 294, 19], name="impedance_box")
+        impedance_faces = self.aedtapp.modeler.select_allfaces_fromobjects([impedance_box.name])
+        assert self.aedtapp.assign_impedance(impedance_faces, "copper")
+        assert self.aedtapp.assign_impedance(impedance_box, "copper")
         impedance_assignment = self.aedtapp.assign_impedance(
             impedance_box.name,
             permeability=1.3,

pyaedt/maxwell.py

@@ -2189,7 +2189,7 @@ def assign_impedance(
         Parameters
         ----------
         geometry_selection : str
-            Objects to apply the impedance boundary to.
+            Faces or objects to apply the impedance boundary to.
         material_name : str, optional
             If it is different from ``None``, then material properties values will be extracted from
             the named material in the list of materials available. The default value is ``None``.
@@ -2216,11 +2216,12 @@ def assign_impedance(
         Examples
         --------
 
-        Create a box and assign impedance boundary to it.
+        Create a box and assign impedance boundary to the faces.
+
+        >>> shield = m3d.modeler.create_box([-50, -50, -50], [294, 294, 19], name="shield")
+        >>> shield_faces = m3d.modeler.select_allfaces_fromobjects(["shield"])
+        >>> impedance_assignment = m3d.assign_impedance(shield_faces, "ShieldImpedance")
 
-        >>> impedance_box = self.aedtapp.modeler.create_box([-50, -50, -50], [294, 294, 19], name="impedance_box")
-        >>> impedance_assignment = self.aedtapp.assign_impedance(impedance_box.name, "InsulatingExample")
-        >>> type(impedance_assignment)
         <class 'pyaedt.modules.Boundary.BoundaryObject'>
 
         """
@@ -2235,7 +2236,12 @@ def assign_impedance(
                 impedance_name = generate_unique_name(impedance_name)
 
             listobj = self.modeler.convert_to_selections(geometry_selection, True)
-            props = {"Objects": listobj}
+            props = {"Objects": [], "Faces": []}
+            for sel in listobj:
+                if isinstance(sel, str):
+                    props["Objects"].append(sel)
+                elif isinstance(sel, int):
+                    props["Faces"].append(sel)
 
             if material_name is not None:
                 props["UseMaterial"] = True