TAI64, TAI64N, TAI64NA implementations for Python.
International Atomic Time (TAI) is the basic standard for measuring time. Universal Coordinated Time (UTC) is derived from TAI by adding or subtracting leap seconds according to the measured rotation speed of the Earth.
TAI64 is a family of formats for TAI times, first implemented in libtai. They have well known serialisations to bytes or hexadecimal.
| Format | Bytes | Resolution | Range |
|---|---|---|---|
| TAI64 | 8 | 1 second | 292 billion years |
| TAI64N | 12 | 1 nanosecond (10**-9 s) | 292 billion years |
| TAI64NA | 16 | 1 attosecond (10**-18 s) | 292 billion years |
The epoch for TAI64 is 1970-01-01 00:00:00 TAI, this is assigned the integer value 2**62.
>>> import tai64
>>> tai64.tai(sec=tai64.EPOCH)
tai64.tai(4611686018427387904)To deserialise a TAI64, TAI64N, or TAI64NA call the from_hex() or
unpack() class method.
>>> tai64.tai.from_hex('400000001dc03c40')
tai64.tai(4611686018926525504)
>>> tai64.tai.unpack(b'@\x00\x00\x00\x1d\xc0<@')
tai64.tai(4611686018926525504)To serialise call the hex() or pack() method
>>> tai64.tai(4611686018926525504).hex()
'400000001dc03c40'
>>> tai64.tai(4611686018926525504).pack()
b'@\x00\x00\x00\x1d\xc0<@'For nanosecond precision (9 decimal places) use tai64.tain(),
or for attosecond (18 decimal places) use tai64.taia().
>>> tai64.tain(4611686018926525504, nano=123).hex()
'400000001dc03c400000007b'
>>> tai64.taia(4611686018926525504, nano=1193046, atto=11259375).hex()
'400000001dc03c400012345600abcdef'
>>> tai64.taia.unpack(b'@\x00\x00\x00\x1d\xc0<@\x00\x124V\x00\xab\xcd\xef')
tai64.taia(4611686018926525504, 1193046, 11259375)- Implement TAI64 <-> UTC
- PyPI package
- Docstrings
- Decide: should
tai()take raw unsigned int (current behaviour) or offset from epoch (time.time()behaviour) - Decide and implement exceptions hierarchy
- Decide and implement
format()behaviour - Decide
int()behaviour of TAI64N and TAI64NA - Decide
__floor__()et al - Decide arithmatic behaviour
- Investigate
CLOCK_TAI
- calends for Go, C/C++, Dart, Javascript, WASM, and PHP
- Go cactus/tai64
- Go paulhammond/tai64
- Javascript tai64
- libtai original C implementation, by D. J. Bernstein.
- Perl Time::TAI64
- Python tai64n
- Python taiconverter
- Rust tai64