The COLSOL is an active column solver to obtain LDLT of a stiffness matrix or reduce and back-substitute the load vector.
A - stiffness matrix stored in compact form.
NN - number of equations.
MAXA - vector containing addresses of diagonal elements of stiffness matrix in A.
V - right-hand side load vector.
A - D and L factors of stiffness matrix.
V - displacement vector.
Note: COLSOL can be used only for symmetric and positive definite stiffness matrices.
