# Read MAT, LUD, RHS and STR Files

The .mat file, .lud file and .rhs file are not generated by default, but can be read externally.

The .mat file contains the elements of the method of moments (MoM) matrix A.

The .lud file is the LU decomposition of the MoM matrix A, which is used for the solution of the system of linear equations $Ax=y$ .

The .rhs file contains the right hand side vector *y*
representing the MoM excitation.

The .str file contains the solution vector x of the system of linear equations $Ax=y$ . This is useful for adding further output requests (for example, adding a far field request) without rerunning the Solver from scratch.