Region object

The purpose of the Region object is to provide a link between an attribute and the geometric or discrete entities to which the attribute is applied. An attribute (Load, BC, IC, etc.) is applied to one or more Region objects; each Region object in turn is associated with a picked Set or Surface or with a named Set or Surface. The Region object provides a unified interface (or "façade") to data and functionality located at the Set or Surface.

A script that applies an attribute to a picked Set or Surface requires the explicit creation of a Region object and will implicitly create a matching internal Set or Surface. Conversely, a script that applies an attribute to a named Set or Surface requires the explicit creation of that Set or Surface (see 39.4) and will implicitly create a region object.

The reference between Region and Set/Surface is by name (user-provided or internal.) If the Set/Surface is suppressed, deleted, or renamed, the Region object will not be able to find the associated Set/Surface, and will communicate that to the attribute, but will not be affected otherwise. If a Set/Surface with the same name becomes available (only possible with user-provided names) the Region object will re-establish the connection. Another way of correcting this problem is to re-apply the attribute.

Wherever a particular Load, BC, IC, etc. command accepts a named set or a named surface, that command will also accept a Region object. For example,

myRegion = regionToolset.Region(edges=edges1)
mdb.models['Model-1'].DisplacementBC(name='BC-1',
    createStepName='Initial', region=myRegion, u1=SET,
    u2=SET)
myRegion = regionToolset.Region(elements=e[1:100])
p = mdb.models['mirror'].parts['COLLAR_MIRROR-1']
p.SectionAssignment(region=myRegion, sectionName='Section-1')

Abaqus does not provide a regions repository; as an alternative, you should assign a variable to a Region object and refer to the variable. The lifecycle of a Region object is similar to the lifecycle of a Leaf object used by display groups; as a result, you should use a Region object immediately after you create it. The contents of a Region object are not intended to survive regeneration. If you use an out-of-date Region object, the script is unlikely to function correctly.

Querying an attribute's Region will return a Region tuple. The contents of the tuple are the set name followed by the owners of the set and three flags expressed as integers. The flags indicate the region space, the type of region and the whether the region is an internal set.

The following topics are discussed:

Access
Region(...)
Region(...)
Members

Access

import regionToolset

Region(...)

This command creates a set-like region. For example,

myRegion = regionToolset.Region(vertices=v[2:4],
    edges=e[4:5]+e[6:9])

The arguments are the same as the arguments to the Set method, except for the name argument.

In most cases, the constructor will be called with only one argument of sequences. The arguments xVertices, xEdges, and xFaces are used to exclude lower-dimension entities and to provide finer control on the content of the region. For example, the following statement defines a region enclosing a square face but without two of its edges:

region = regionToolset.Region(faces=f[3:4], xEdges=e[1:3])

Path

Region

Required arguments

None.

Optional arguments

elements: A sequence of Element objects. The default value is None.
nodes: A sequence of Node objects. The default value is None.
vertices: A sequence of Vertex objects. The default value is None.
edges: A sequence of Edge objects. The default value is None.
faces: A sequence of Face objects. The default value is None.
cells: A sequence of Cell objects. The default value is None.
referencePoints: A sequence of ReferencePoint objects. The default value is an empty sequence.
xVertices: A sequence of Vertex objects that excludes specific vertices from the region. The default value is None.
xEdges: A sequence of Vertex objects that excludes specific edges from the region. The default value is None.
xFaces: A sequence of Vertex objects that excludes specific faces from the region. The default value is None.
skinFaces: A tuple of tuples specifying a skin name and the sequence of faces associated with this skin. Valid only for geometric regions on 3D and 2D parts.
skinEdges: A tuple of tuples specifying a skin name and the sequence of edges associated with this skin. Valid only for geometric regions on Axisymmetric parts.
stringerEdges: A tuple of tuples specifying a stringer name and the sequence of edges associated with this stringer. Valid only for geometric regions on 3D and 2D parts.

Return value

A Region object.

Exceptions

None.

Region(...)

This command creates a surface-like region. For example,

myRegion = regionToolset.Region(side1Faces=f[12:14])

The arguments are the same as the arguments to the Surface method, except for the name argument.

Path

Region

Required arguments

None.

Optional arguments

In most cases, you will provide only one argument of sequences.

side1Faces: A sequence of Face objects (surface applies to SIDE1 of face). The default value is None.
side2Faces: A sequence of Face objects (surface applies to SIDE2 of face). The default value is None.
side12Faces: A sequence of Face objects (surface applies to both SIDE1 and SIDE2 of face). The default value is None.
side1Edges: A sequence of Edge objects (surface applies to SIDE1 of edge). The default value is None.
side2Edges: A sequence of Edge objects (surface applies to SIDE2 of edge). The default value is None.
end1Edges: A sequence of Edge objects (surface applies to END1 of edge). The default value is None.
end2Edges: A sequence of Edge objects (surface applies to END2 of edge). The default value is None.
circumEdges: A sequence of Edge objects (surface applies circumferentially to edge). The default value is None.
face1Elements: A sequence of Element objects (surface applies to FACE1 of element). The default value is None.
face2Elements: A sequence of Element objects (surface applies to FACE2 of element). The default value is None.
face3Elements: A sequence of Element objects (surface applies to FACE3 of element). The default value is None.
face4Elements: A sequence of Element objects (surface applies to FACE4 of element). The default value is None.
face5Elements: A sequence of Element objects (surface applies to FACE5 of element). The default value is None.
face6Elements: A sequence of Element objects (surface applies to FACE6 of element). The default value is None.
side1Elements: A sequence of Element objects (surface applies to SIDE1 of element). The default value is None.
side2Elements: A sequence of Element objects (surface applies to SIDE2 of element). The default value is None.
side12Elements: A sequence of Element objects (surface applies to both SIDE1 and SIDE2 of element). The default value is None.
end1Elements: A sequence of Element objects (surface applies to END1 of element). The default value is None.
end2Elements: A sequence of Element objects (surface applies to END2 of element). The default value is None.
circumElements: A sequence of Element objects (surface applies to circumference of element). The default value is None.

Return value

A Region object.

Exceptions

None.

Members

The Region object has no members.