The SysML Allocation matrix enables you to analyze, create, and modify Allocate relationships. Rows in the matrix represent an element that can be the client element of the Allocate relationship. Columns in the matrix represent elements that can be the supplier elements of the Allocate relationship. You can set your own element types that you want to allocate in the criteria area or  you can create a matrix with predefined element types in the criteria area by selecting one of the SysML Allocation Matrix mode.