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An S3 class with methods for totally ordered indexed observations. It is particularly aimed at irregular time series of numeric vectors/matrices and factors. zoo's key design goals are independence of a particular index/date/time class and consistency with ts and base R by providing methods to extend standard generics.
Package details 


Author  Achim Zeileis [aut, cre] (<https://orcid.org/0000000309183766>), Gabor Grothendieck [aut], Jeffrey A. Ryan [aut], Joshua M. Ulrich [ctb], Felix Andrews [ctb] 
Maintainer  Achim Zeileis <Achim.Zeileis@Rproject.org> 
License  GPL2  GPL3 
Version  1.88 
URL  http://zoo.RForge.Rproject.org/ 
Package repository  View on CRAN 
Installation 
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