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The uc.check() function checks whether the roots of a given polynomial lie outside the Unit circle. You can also easily draw an unit circle.
Package details 


Author  Jonathan Berrisch 
Maintainer  Jonathan Berrisch <Jonathan@Berrisch.biz> 
License  GPL3 
Version  0.1.3 
URL  https://github.com/BerriJ/UnitCircle 
Package repository  View on CRAN 
Installation 
Install the latest version of this package by entering the following in R:

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