The solution of this problem must be preceded by the calculation of element stiffness matrices, and the following conditions apply:

• The same elements can be used as in a Linear elastostatics.
• General symmetry or periodicity cannot be used.

The right-hand side (the load case) does not matter in this case; therefore, only quantities specifying material properties and displacement boundary conditions can be considered in the first load case (AS 1) in the name.i2 file.

The input data is written into the name.iM text file. The program generates consistent (thus positive definite) mass matrices $\mathbf{M}$ of elements.

The input data is written into the name.iR text file. The program factorizes the matrix $$\sum(\mathbf{K}+a_0\mathbf{M}+a_1\mathbf{C}),$$ where $\sum(\dots)$ denotes global (not element) matrices. The consistent mass matrix $\sum(\mathbf{M})$ is positive-definite, and the matrix $\sum(a_0\mathbf{M}+a_1\mathbf{C})$ usually exhibits the same property. Since quasi-static processes are not considered here, the matrix $\sum(\mathbf{K}+a_0\mathbf{M}+a_1\mathbf{C})$ will then also be positive-definite, even if $\sum(\mathbf{K})$ is only positive-semidefinite. It is recommended to check that no pivots smaller than $\mathtt{PIVOT}$ are reported in the name.oR file.

The input data is written into the name.i5 text file, where the problem type key $\mathtt{KPROB}=1$.