[R] Convert Time from HH.mm to Decimal hours?

[Alan E. Davis]

I have data in Unixtime that I wish to plot several ways.  I have
learned to convert to a vector of time strings, and for the sake of
plotting times of day vs. heights of tide (to examine seasonality
component) I can extract HH:mm pretty swiftly and readily from
Unixtime using emacs calc.  However, I have had trouble with decimal
hours that are needed (or perhaps not) for at least one of the polar
plotting packages.

Is there an easy way to do this in R?

Thank you for any ideas.  (I have learned how to do simple polar plots
by way of a couple of people on this list.  Thanks very much.)

Alan

-- 
Alan Davis, Kagman High School, Saipan  lngndvs at gmail.com

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--------Richard Stallman

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