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.
- 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.
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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