Here type sets the number of integration points in an element. It should be set to -minimal or to -maximal.
For -tria3 elements and -tet4 elements, the integration point will be located in the middle with -minimal integration, or the integration points are located in the nodes with -maximal integration.
For other elements, if -minimal is used then the number of integration points in a direction is set equal to the number of nodes in the direction minus 1, and gauss integration is used. If for the other elements -maximal is used then the number of integration points in a direction is set equal to the number of nodes in the direction, and lobatto integration is used.
Default -minimal is used for -bar2, -tria3 and -tet4 elements; it is default -maximal otherwise.
The index specifies the element_group, see element_group.