Evaluate Winding Numbers through Cauchy Indices

Title:	Evaluate Winding Numbers through Cauchy Indices
Author:	Wenda Li
Submission date:	2017-10-17
Abstract:	In complex analysis, the winding number measures the number of times a path (counterclockwise) winds around a point, while the Cauchy index can approximate how the path winds. This entry provides a formalisation of the Cauchy index, which is then shown to be related to the winding number. In addition, this entry also offers a tactic that enables users to evaluate the winding number by calculating Cauchy indices.
BibTeX:	@article{Winding_Number_Eval-AFP, author = {Wenda Li}, title = {Evaluate Winding Numbers through Cauchy Indices}, journal = {Archive of Formal Proofs}, month = oct, year = 2017, note = {\url{http://isa-afp.org/entries/Winding_Number_Eval.html}, Formal proof development}, ISSN = {2150-914x}, }
License:	BSD License
Depends on:	Budan_Fourier, Sturm_Tarski
Used by:	Count_Complex_Roots, Zeta_Function
Status: [ok]	This is a development version of this entry. It might change over time and is not stable. Please refer to release versions for citations.