
D.14.1 phindex_lib
 Library :
 phindex.lib
 Purpose:
 Procedures to compute the index of real analytic vector fields
 Author:
 Victor Castellanos
 Note:
 To compute the PoincareHopf index of a real analytic vector field
with an algebraically isolated singularity at 0 (w. an a. i. s),
we use the algebraic formula for the degree of the real analytic map
germ found by EisenbudLevine in 1997. This result was also proved by
Khimshiashvili. If the isolated singularity is non algebraically
isolated and the vector field has similar reduced complex zeroes of
codimension 1, we use a formula as the EisenbudLevine found by Victor
Castellanos, in both cases is necessary to use a local order (ds,...).
To compute the signature of a quadratic form (or symmetric matrix)
we use the method of Lagrange.
Procedures:
