# geometry assign-groups command

Syntax

geometry assign-groups keyword <range>

Primary keywords:

This command assigns group names to objects based on their relation to geometric sets. Use of the group logic is described in Group. All polygons in all sets are assigned a surface number – polygons that are connected topologically will be assigned the same number. From the position of each object, a ray is projected in the direction specified by the projection keyword. FLAC3D will count the number of times that ray intersects each surface, and use that information to assign a group name.

For instance, if no surfaces are intersected, then the group name “No Intersections” is assigned. Each different combination of intersections is assigned a capital letter. For examples, objects that intersect the surface number 2 once and surface number 3 twice might be assigned the letter “D”. The group names are assigned to all objects in the range.

[CS: broken link in next. Where should it go? What was the intention here?] See ref-geometrygroupassignment- for further discussion and examples on the use of this command.

[CS: in the keywords below, the term ‘Type Block’ is/was intended to be a link to… ?? Mystery to be resolved]

The following keywords are available to select the type of object group names are assigned to:

data keyword

This assigns group names to the set of user-define data based on their location.

scalar keyword [assignoptions]

Assign groups to the user-defined scalar data using one or more of the common option keywords (see below).

tensor keyword [assignoptions]

Assign groups to the user-defined tensors data using one or more of the common option keywords (see below).

vector keyword [assignoptions]

Assign groups to the user-defined vectors data using one or more of the common option keywords (see below).

structure keyword

This assigns group names to structural data (elements, nodes, or links). Elements are checked at their centroids.

beam keyword [assignoptions]

Assign groups to beams using one or more of the common option keywords (see below).

cable keyword [assignoptions]

Assign groups to cables using one or more of the common option keywords (see below).

geogrid keyword [assignoptions]

Assign groups to geogrids using one or more of the common option keywords (see below).

liner keyword [assignoptions]

Assign groups to liners using one or more of the common option keywords (see below).

Assign groups to links using one or more of the common option keywords (see below).

node keyword [assignoptions]

Assign groups to nodes using one or more of the common option keywords (see below).

pile keyword [assignoptions]

Assign groups to piles using one or more of the common option keywords (see below).

shell keyword [assignoptions]

Assign groups to shells using one or more of the common option keywords (see below).

zone <grid-point> keyword [assignoptions]

Assign groups to zones (or grid points if the option grid-point keyword is given) using a $$Type Block$$ keyword.

Block of Common Options for Group Assignment

The following keywords may be used to modify the commands:

projection v

Specifies the direction the projection is made from each location considered. By default this direction is (0,0,1).

set s

Specifies the name of the set to use. More than one set name may be specified. By default, the current selected set is used.

slot i

Specifies the slot that the group names will be assigned in. If not specified the slot name is ‘Default’.