Stiffness/Flexibility Matrix K11/F11
Input of the sub-matrix K11 (Stiffness) or F11 (flexibility)
The Matrix K11 or F11 describes the interaction between the (local) degrees of freedom of the start node. The input is omitted when the number of the start node is zero.
Only half of the coefficients need to be entered due to the symmetry of the submatrix.