Add API documentation for the material module

src/ifcopenshell-python/ifcopenshell/api/material/edit_layer.py

@@ -18,11 +18,45 @@
 
 
 class Usecase:
-    def __init__(self, file, **settings):
+    def __init__(self, file, layer=None, attributes=None, material=None):
+        """Edits the attributes of an IfcMaterialLayer
+
+        For more information about the attributes and data types of an
+        IfcMaterialLayer, consult the IFC documentation.
+
+        :param layer: The IfcMaterialLayer entity you want to edit
+        :type layer: ifcopenshell.entity_instance.entity_instance
+        :param attributes: a dictionary of attribute names and values.
+        :type attributes: dict, optional
+        :param material: The IfcMaterial entity you want the layer to be made
+            from.
+        :type material: ifcopenshell.entity_instance.entity_instance, optional
+        :return: None
+        :rtype: None
+
+        Example::
+
+            # Let's create two materials typically used for steel stud partition
+            # walls with gypsum lining.
+            gypsum = ifcopenshell.api.run("material.add_material", model, name="PB01", category="gypsum")
+            steel = ifcopenshell.api.run("material.add_material", model, name="ST01", category="steel")
+
+            # Create a material layer set to contain our layers.
+            material_set = ifcopenshell.api.run("material.add_material_set", model,
+                name="GYP-ST-GYP", set_type="IfcMaterialLayerSet")
+
+            # Now let's use those materials as three layers in our set, such
+            # that the steel studs are sandwiched by the gypsum. Let's imagine
+            # we're setting the layer thickness in millimeters.
+            layer = ifcopenshell.api.run("material.add_layer", model, layer_set=material_set, material=gypsum)
+            ifcopenshell.api.run("material.edit_layer", model, layer=layer, attributes={"LayerThickness": 13})
+            layer = ifcopenshell.api.run("material.add_layer", model, layer_set=material_set, material=steel)
+            ifcopenshell.api.run("material.edit_layer", model, layer=layer, attributes={"LayerThickness": 92})
+            layer = ifcopenshell.api.run("material.add_layer", model, layer_set=material_set, material=gypsum)
+            ifcopenshell.api.run("material.edit_layer", model, layer=layer, attributes={"LayerThickness": 13})
+        """
         self.file = file
-        self.settings = {"layer": None, "attributes": {}, "material": None}
-        for key, value in settings.items():
-            self.settings[key] = value
+        self.settings = {"layer": layer, "attributes": attributes or {}, "material": material}
 
     def execute(self):
         for name, value in self.settings["attributes"].items():