fe assemble assemble ( ) assemble (M, C) Computes and returns the global stiffness matrix by computing the local stiffness matrices and assembling them into the global matrix. For transient problems, if M is specified then it will contain the global mass matrix on return. Similarly, C will contain the global damping matrix. All matrices are compact. fe clear_nodes clear_nodes ( ) Clears the displacements and equivalent nodal force vectors for all nodes in the current problem. fe compute_modes compute_modes (K, M) compute_modes (K, M, X) Compute the modes for the given stiffness matrix, K, and mass matrix, M. The result is the vector of eigenvalues. If X is specified then it will contain the matrix of eigenvectors upon return. fe compute_stresses compute_stresses (e) Not available yet. fe construct_forces construct_forces ( ) construct_forces (t) Constructs and returns the global nodal force vector based on all nodal forces and the global DOFs active at those nodes. For transient problems, t may be a scalar expression used to specify the current time. If t is missing then it is assumed to be zero. fe find_dofs find_dofs ( ) Computes the set of active DOFs for the current problem. As a result, the DOF-related fields of the problem structure are initialized. The number of active DOFs is returned. fe global_dof global_dof (n, d) Returns the global DOF corresponding to a local DOF. The local DOF is specified by its node, n, and the DOF, d. The node may be specified as either a node object or a node number. fe integrate_hyperbolic integrate_hyperbolic (K, M, C) integrate_hyperbolic (K, M, C, p) Solves the discrete equation of motion, Ma + Cv + Kd = F, using Newmark's method with the Hilbert-Hughes-Taylor alpha correction for improved accuracy with numerical damping. The result is a matrix of nodal displacements, with each column corresponding to a single time step. If the nodes have been renumbered then p should be used to specify the permutation vector. The sizes of the matrices must be consistent with the definition of the problem. Compact matrices are expected. fe integrate_parabolic integrate_parabolic (K, M) integrate_parabolic (K, M, p) Solves the discrete parabolic differential equation Mv + Kd = F using a generalized trapezoidal method. If the nodes have been renumbered then p should be used to specify the permutation vector. The sizes of the matrices must be consistent with the definition of the problem. Compact matrices are expected. fe local_dof local_dof (g) local_dof (g, l) Returns the number of the node corresponding to the global DOF, g. If l is specified the it will contain the local DOF on return. (The number of the node is returned rather than the node object itself since the nodes may have been renumbered.) fe remove_constrained remove_constrained (K) Removes the rows and columns of K at all DOFs with a fixed boundary condition and returns the new matrix. K is not modified. K should with be either a symmetric matrix or a column vector. The size of K must be consistent with the definition of the problem. fe renumber_nodes renumber_nodes ( ) Renumbers the nodes of the current problem using the Gibbs-Poole-Stockmeyer and Gibbs-King node renumbering algorithms for bandwidth and profile reduction. The result is a permutation vector of the node numbers. fe restore_numbers restore_numbers (p) Restores the original node numbering of the current problem. The permutation vector is specified by p. The return value is always null. fe set_up set_up (e) set_up (e, s) Not available yet. fe solve_displacements solve_displacements (K, f) Solves the linear system Kd = f for the vector of global nodal displacements. The sizes of the inputs must be consistent with the definition of the problem. Additionally, K and f should both be condensed. K is expected to be compact. fe zero_constrained zero_constrained (K) Zeroes the rows and columns of K at all DOFs with a fixed boundary condition and returns the new matrix. K is not modified. K should with be either a symmetric matrix or a column vector. If K is a matrix then a one is placed on the corresponding diagonal. The size of K must be consistent with the definition of the problem.