Add examples from Operators section to Field API

src/ansys/dpf/core/field.py

@@ -51,6 +51,14 @@ class Field(_FieldBase):
     The field's scoping defines the order of the data, for example: the first ID in the
     ``scoping`` identifies to which entity the first ``entity data`` belongs.
 
+    The minimum requirement for a well defined field is for it to have a dimensionality
+    (scalar, three components vector, six components symmetrical matrix, and so on), a location
+    ("Nodal", "Elemental", "ElementalNodal", "Timefrq"), a data vector and a scoping with IDs.
+    You can also set the number of shell layers. If the field has one elementary data by entity
+    (elementary data size equals the number of components for "Nodal" or "Elemental" field for example),
+    then the data vector can be set directly. If a more complex field is required
+    ("ElementalNodal" field for example), the data can be set entity by entity.
+
     For more information, see the `Fields container and fields
     <https://dpf.docs.pyansys.com/version/stable/user_guide/fields_container.html>`_
     documentation section.
@@ -81,12 +89,42 @@ class Field(_FieldBase):
     --------
     Create a field from scratch.
 
-    >>> from ansys.dpf.core import fields_factory
     >>> from ansys.dpf.core import locations
     >>> from ansys.dpf import core as dpf
     >>> field_with_classic_api = dpf.Field()
     >>> field_with_classic_api.location = locations.nodal
-    >>> field_with_factory = fields_factory.create_scalar_field(10)
+
+
+    Create a field from scratch for the most common dimensionalities
+    >>> from ansys.dpf import core as dpf
+    >>> num_entities = 2
+    >>> my_field = dpf.Field(num_entities, dpf.natures.scalar, "Nodal")
+    >>> my_field = dpf.Field(num_entities, dpf.natures.vector, "ElementalNodal")
+    >>> my_field = dpf.Field(num_entities, dpf.natures.symmatrix, "Elemental")
+    >>> my_scoping = dpf.Scoping()
+    >>> my_scoping.location = "Elemental"
+    >>> my_scoping.ids = list(range(1,3))
+    >>> my_field.scoping = my_scoping
+
+    Add all the data at once
+
+    >>> from ansys.dpf import core as dpf
+    >>> my_data = [1.0,1.0,1.0,0.0,0.0,0.0,1.0,1.0,1.0,0.0,0.0,0.0]
+    >>> my_field.data = my_data
+
+    Add data entity by entity
+    >>> from ansys.dpf import core as dpf
+    >>> my_elem_data = [1.0,1.0,1.0,0.0,0.0,0.0]
+    >>> my_field.append(my_elem_data, scopingid=1)
+    >>> my_field.append(my_elem_data, scopingid=2)
+
+    Create a field using the fields factory
+
+    >>> from ansys.dpf.core import fields_factory
+    >>> from ansys.dpf.core import locations
+    >>> from ansys.dpf import core as dpf
+    >>> my_scalar_field = fields_factory.create_scalar_field(2)
+    >>> my_scalar_field.data = [1.0, 3.0]
 
     Extract a displacement field from a transient result file.