Time and date specification

Time and date formats are specified with the following expressions. This is useful to read or write files with custom time and date format. See for instance the documentation of gptime and Custom ASCII formats.

Expression	Comments
C	'C' locale is considered for numbers (dot for decimal separation and omit group separators). Place it at the beginning of the format.
D	For input only, unspecified fields of the format are silently ignored and set to their default values. Place it at the beginning of the format.
d	The day as number without a leading zero (1 to 31)
dd	The day as number with a leading zero (01 to 31)
ddd	The abbreviated localized day name (e.g. 'Mon' to 'Sun')
dddd	The long localized day name (e.g. 'Monday' to 'Sunday')
M	The month as number without a leading zero (1-12)
MM	The month as number with a leading zero (01-12)
MMM	The abbreviated localized month name (e.g. 'Jan' to 'Dec')
MMMM	The long localized month name (e.g. 'January' to 'December')
yy	The year as two digit number (00-99)
yyyy	The year as four digit number
h	The hour without a leading zero (0 to 23 or 1 to 12 if AM/PM display)
hh	The hour with a leading zero (00 to 23 or 01 to 12 if AM/PM display)
H	The hour without a leading zero (0 to 12)
HH	The hour with a leading zero (00 to 12)
m	The minute without a leading zero (0 to 59)
mm	The minute with a leading zero (00 to 59)
s	The second without a leading zero (0 to 59)
ss	The second with a leading zero (00 to 59)
sz	The second including fraction of seconds (0 to 60, excluding 60)
ssz	The second including fraction of seconds (00 to 60, excluding 60)
z	The milliseconds without leading zeroes (0 to 999)
zzz	The milliseconds with leading zeroes (000 to 999)
AP	Interpret as an AM/PM time. AP must be either "AM" or "PM".
ap	Interpret as an AM/PM time. ap must be either "am" or "pm".
'	Any text inside single quotes is considered as a regular expression.

Any text even outside quotes is considered verbatim if it does not match one of the above expressions. In general, to match extra characters, it is safer to put them inside single quotes.

Examples

For input format

Input text	Format	Date time value
11 PM	H AP	1970-01-01 23:00:00.000000
11 pm	H ap	1970-01-01 23:00:00.000000
11	H	1970-01-01 11:00:00.000000
23	H	expected a number between 0 and 12: '23'
23	h	1970-01-01 23:00:00.000000
23 am	h ap	expected a number between 1 and 12: '23'
11:10:08.345	h:m:s	1970-01-01 11:10:08.000000
11:10	h:m:s	truncated date/time specification: '11:10'
11:10	Dh:m:s	1970-01-01 11:10:00.000000
11:10:08.345	h:m:ss	1970-01-01 11:10:08.000000
11:10:08.345	h:m:sz	1970-01-01 11:10:08.345000
11:10:08.345	h:m:ssz	1970-01-01 11:10:08.345000
It's 11:10 am	'It.s +'h:m ap	1970-01-01 11:10:00.000000
11:10 UTC	h:m UTC	1970-01-01 11:10:00.000000
11:10 apéro	h:m apéro	expected am or pm: 'ap'
11:10 apéro	h:m	unmatched characters: ' apéro'

For ouput format

Date time value	Format	Output
1970-01-01 23:00:00.000000	H AP	11 PM
1970-01-01 23:00:00.000000	h ap	23 pm
1970-01-01 11:10:08.345000	h:m:s	11:10:8
1970-01-01 11:10:08.345000	h:mm:s	11:10:08
1970-01-01 11:10:08.345000	hh:mm:sz	11:10:8.345000
1970-01-01 11:10:08.345000	hh:mm:ssz	11:10:08.345000
1970-01-01 11:10:08.345000	hh:mm:ssz UTC	11:10:08.345000 UTC