manipulating the Date & Time classes

Hello,

? ?This is mostly to developers, but in case I missed something in my
literature search, I am sending this to the broader audience.


? - Are there any plans in the works to make "time" classes a bit more
? friendly to the rest of the "R" world? ?I am not suggesting to allow for
? fancy functions to manipulate times, per se, or to figure out how to
? properly "add" times or anything complicated. ?Just some fixes to make it
? easier to work with the "time" classes. ?Here is a sampling of some strange
? bugs with the time classes that, to my knowledge, don't exist with any other
? core classes:
? ? ?1. you cannot "unlist" a time without losing the class. ?E.g., if you
? ? ?unlist "2010-12-14 20:25:40" (POSIXct), you get "1292387141", at
least on my
? ? ?OS & with my time zone. ?Regardless of the exact number, unlisting a time
? ? ?class converts it to a numeric.

unlist(Sys.time())

? ? ? ? - upon converting to a numeric, it seems there is an underlying,
? ? ? ? assumed origin of "1970-01-01 00:00:00". ?However, this same
assumption does
? ? ? ? not underlie the conversion *back* to a POSIX time, e.g., through
? ? ? ? as.POSIXct() function. ?Therefore, whenever a time is "accidentally"
? ? ? ? converted to a numeric, I have to force it back to a time through
? ? ? ? as.POSIXct(), *providing my own details* as to the origin. ?There
? ? ? ? is no easy way to find the underlying origin. ?This makes me
nervous for any
? ? ? ? persistent functions I create. ?If the underlying origin ever
changes, then
? ? ? ? all this code will be inaccurate. ?Maybe the origin will
never change, but
? ? ? ? regardless it makes more sense to allow for the same underlying origin
? ? ? ? default for "as.POSIXct" that is used when unlisting, or
similar activities
? ? ? ? that force the time into a numeric.

? ? ? ? 2. you cannot perform functions that otherwise seem trivial, such
? ? ?as a "max" or "min". ?I understand why, for instance, adding is
hard. ?But
? ? ?what about max or min? ?Greater than or less than are possible, as is
? ? ?order(). ?I have my own simple scripts using these 2 functions
in order to
? ? ?create a "max" & "min" for times, but it would be nice to have something
? ? ?vetted & official.

min(Sys.time()+1:10)

max(Sys.time()+1:10)

? ?If others could chime in with any strange behaviors they've seen in
working with times, maybe we could get a critical mass of issues that are
worthy of an overhaul.

? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?Thanks & Regards,
? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ?Mike


"Telescopes and bathyscaphes and sonar probes of Scottish lakes,
Tacoma Narrows bridge collapse explained with abstract phase-space maps,
Some x-ray slides, a music score, Minard's Napoleanic war:
The most exciting frontier is charting what's already here."
?-- xkcd

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