1. A design tool for designing a physical system by extracting a parameter of a modeled component of the system, said tool comprising: a matrix generator for producing signals indicative of a system of equations representative of the operation in the system of a plurality of segments defining said component, said system of equations forming a matrix of signals; a memory for storing said matrix; a submatrix controller for acting on said memory to subdivide said matrix into a hierarchy of submatrices, said hierarchy defining at least one parent submatrix and a plurality of child submatrices each with a rank; a UV decomposition generator for compressing at least one of said child submatrices; a submatrix merger for combining a plurality of said child submatrices to produce a merged submatrix; a rank comparator for selecting either said merged submatrix or a plurality of said child submatrices based on their relative rank; an iterative matrix solver for producing a signal representing solution of said matrix using said selected submatrix or submatrices; and a parameter solver for processing said solution signal to generate a signal representative of said parameter and using it to define the structure of the component in the system.