\ref tui_create_group_on_geometry "Create a Group on Geometry"
operation.
+<br><h2>Creation of groups using existing groups and sub-meshes.</h2>
+
+Application provides possibility to create new <b>standalone</b> groups using existing standalone groups, groups on geometry and sub-meshes. This functionality is implemented using "Select from" group box of "Create group" dialog box described above.
+
+This functionality is described on the example of creating new group from existing standalone groups and groups on geometry.
+
+Imagine there are group G1. It can be standalone group or group on geometry.
+
+To create group G2 containing all entities of group G1 and a faces graphically selected in 3D view following steps can be performed:
+<ul>
+<li>User opens "Create group" dialog box.</li>
+<li>The user specifies "Face" type of entities and "G2" name of group.</li>
+<li>The user checks "Group" check-box of "Select From" group box.</li>
+<li>The user selects G1 group in object browser or 3D view.</li>
+<li>The user presses "Add" push button of "Content" group box. "Id Elements" list-box is filled with identifiers of faces belonging to group G1.</li>
+<li>The user selects other faces in 3D view.</li>
+<li>The user presses "Apply" button. System creates group G2.</li>
+</ul>
+
+Please note that group G2 does not have a references to source group G1. It contains list of faces identifiers only. So if G1 group will be changed group G2 will remain unmodified.
+
+<br>
+\anchor gui_create_dim_group
+<h2>Creating groups of entities from existing groups of superior dimensions</h2>
+
+Application provides possibility for creating groups of entities from existing groups of superior dimensions. For example, it is possible to create group of nodes using list of existing groups of faces.
+
+To create groups of entities from existing groups of superior dimensions, in the \b Mesh menu select <b>Group of underlying entities</b>.<br>
+
+The following dialog box will appear:
+
+\image html dimgroup_dlg.png
+
+In this dialog box you should specify the name of the resulting group, types of entities and set of source groups.
+
+For example, we have two source Volume groups illustrated on the figure below
+
+\image html dimgroup_src.png
+<center>Source groups</center>
+
+In this case we obtain following results for Faces, Edges and Nodes.
+
+\image html dimgroup_2d.png
+<center>Faces</center>
+
+\image html dimgroup_1d.png
+<center>Edges</center>
+
+\image html dimgroup_0d.png
+<center>Nodes</center>
+
+<b>See Also</b> a sample TUI Script of a
+\ref tui_create_dim_group "Creating groups of entities from existing groups of superior dimensions"
+operation.
*/
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