[File: Boundary_condition_flag.txt] Each node requires an input boundary condition flag. It consists of one digit per degree of freedom, and is denoted by the integer array IBC within the program. IBC (J) = Parameters constraint indicators at node J. (Right justified) Digit L equals constraint type of parameter L. (Default=0) NOTE: The IBC boundary condition indicator is an integer consisting of N_G_DOF digits that are constraint flags for the corresponding degrees of freedom at that node. The first DOF is the leftmost flag digit while the N_G_DOF-th DOF is the rightmost flag digit. A zero denotes an unknown with no boundary conditions or constraint. Each digit can be from 0 to 9 but only 0,1,2,3 are supported now. Values other than 0 (free) or 1 (given value) rarely occur. EXAMPLE, for N_G_DOF = 1 IBC Flag_1 Remarks 0 0 One free unknown 1 1 One type 1 constraint (assigned value) 2 2 DOF is part of a type 2 constraint pair 3 3 DOF is part of a type 3 constraint triplet EXAMPLE, for N_G_DOF = 3 IBC Flag_1 Flag_2 Flag_3 Remarks 000 0 0 0 Three free unknowns 010 0 1 0 One type 1 constraint (assigned value) 110 1 1 0 Two type 1 constraints (assigned values) 002 0 0 2 DOF 3 has type 2 constraint 022 0 2 2 DOF's 2 & 3 have type 2 constraint 333 3 3 3 All coupled to type 3 constraint The assigned value for each type 1 (essential) BC is given elsewhere in the input. Likewise, the linear constraint equation (MPC) for each type 2 or 3 constraint is given elsewhere. [End: Boundary_condition_flag.txt]