CIF Date and Time
Many CIF data items take as value a date or a date and time (e.g.
_audit_creation_date) or may include a date/time string as part of their
expected content (e.g. _audit_update_record). The convention for
expressing a date/time string is as follows, and is consistent with the ISO
standard ISO 8601:1988(E).
A unique instant in time may be defined by concatenating
- a date string in the format YYYY-MM-DD, where YYYY
represents the year number in the Occidental Gregorian calendar, MM
is the (zero-padded) month number, and DD is the (zero-padded) day
number
and optionally
- the character "T" followed by a time in the 24-hour clock format
hh:mm:ss, where hh, mm and ss are respectively
the hour, minute and second, zero-padded as necessary
- a plus or minus character, corresponding to time zone offsets
respectively east and west of Greenwich, followed by the offset value in the
format hh:mm (representing hours and minutes difference from
Coordinated Universal Time)
Depending on the required precision of the date/time, the full string may be
truncated from the right as appropriate.
Examples
-
1997-08-12T13:55:58-05:00
-
Four minutes and two seconds before two o'clock on the afternoon
of 12 August 1997, at the latitude of Hamilton, Ontario (corresponding to
supper time at Greenwich).
-
1997-08-12T13:55:58+05:45
-
Four minutes and two seconds before two o'clock on the afternoon
of 12 August 1997, at the latitude of Kathmandu, Nepal
-
1997-08-12T13:55:58
-
Four minutes and two seconds before two o'clock on the afternoon
of 12 August 1997, local time
-
1997-08-12T13:55
-
Five minutes to two, afternoon of 12 August 1997
-
1997-08-12
-
12 August 1997
Updated 12 August 1997
Copyright © 1997 International Union of Crystallography
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