README

TAIDER -- storing and manipulating TAI dates and times in Erlang
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Taider is the Erlang port of libtai. As such, it is aimed at providing
the means for storing and manipulating dates and times in Erlang.

As libtai, Taider supports two time scales: (1) TAI64, covering a few 
hundred billion years with 1-second precision; (2) TAI64NA, covering 
the same period with 1-attosecond precision. Both scales are defined 
in terms of TAI, the current international real time standard.

Taider provides an internal format for TAI64, record tai, designed for
fast time manipulations. The taider_tai:pack() and taider_tai:unpack() 
functions convert between record tai and the portable 8-byte TAI64 
storage format introduced by libtai. Taider provides similar internal
and external formats for TAI64NA.

Taider provides a record, caldate, to store dates in year-month-day 
form. It can convert record caldate, under the Gregorian calendar, 
to a modified Julian day number for easy date arithmetic.

Taider provides also a caltime record to store calendar dates and 
times along with UTC offsets. It converts from record tai to record 
caltime in UTC, accounting for leap seconds, for accurate date and 
time display. It also converts back from record caltime to record 
tai for user input.

Taider is intended to be an homophone of tider (tide in Old English 
meant "time period").