On the equivalence of the invariant subdistribution algorithm and the structure algorithm (Q1087512)

This paper contains a study of the structure at infinity for nonlinear systems. Recently formal zeros at infinity for nonlinear systems have been introduced in a geometric manner by the reviewer and \textit{J. M. Schumacher} [IEEE Trans. Autom. Control AC-30, 566-573 (1985; Zbl 0558.93042)]. This approach is based on a generalization of \textit{L. M. Silverman}'s structure algorithm for the inversion of a linear system [ibid. AC-14, 270-276 (1969)]. It is shown that under weaker conditions one can obtain Hirschorn's invertibility indices, another generalization of Silverman's algorithm [cf. \textit{R. M. Hirschorn}, ibid. AC-24, 855-865 (1979; Zbl 0427.93020)].