====== Group Command ======

__GROU__P,<ng>,<type>

activates or creates the element group number <ng>. The parameter <type> can be typed as a number or a string.

^Group Type (number) ^Group Type (string) ^Number of Nodes ^Description  ^
| 1 | SOLID | 8 | 3D solid element |
| 2 | BEAMS | 3 | 3D beam elements |
| 3 | SHELL | 3 or 4 | 3D plate/shell elements|
| 4 | PLANE | 3 or 4 | 2D plane strain solid elements|
| 5 | TSHELL | 3 or 4| 3D Thick Shell elements |
| 7 | SPRING | 2 | 3D spring elements (translation or rotation)|
| 8 | GENERAL | 2 | 3D stiffness/mass generalized element|
| 9 | LOVEWAVE | 3 or 4 | 1D plane Love wave elements|

The excavated soil zones may be modeled using the following element types:
  * SOLID
  * PLANE
  * LOVEWAVE

The information (excepting nodes) which may be assigned to elements of each type is shown in the following table:


^Group Type ^Element Data ^Instruction ^
| SOLID | material / soil layer index | [[com:MSET]] |
| ::: | element type | [[com:ETYPE]] |
| BEAMS  | material index | [[com:MSET]] |
| ::: | real property index | [[com:RSET]] |
| ::: | I node release code | [[com:KI]] |
| ::: | J node release code | [[com:KJ]] |
| SHELL | material index | [[com:MSET]] |
| ::: | thickness | [[com:THICK]] |
| ::: | element type | [[com:ETYPE]] |
| TSHELL | material index | [[com:MSET]] |
| ::: | thickness | [[com:THICK]] |
| ::: | element type | [[com:ETYPE]] |
| ::: | Integration Order | [[com:EINT]] |
| PLANE | material / soil layer index | [[com:MSET]] |
| ::: | element type | [[com:ETYPE]] |
| SPRING | spring property index | [[com:RSET]] |
| LOVEWAVE | material / soil layer index | [[com:MSET]] |
| ::: | element type | [[com:ETYPE]] |
| GENERAL | matrix property index | [[com:RSET]] |

**Note:** All the elements in the system must be grouped separately according to their type. Gaps in element numbering are not allowed. Use the [[com:ECOMPR]] instruction to compress groups with element gaps. It is possible to use more than one group for an element type. For example, all structural brick elements may be considered as one group and all excavated soil elements as another group.