Converts date and time values to fractional Julian date values.
DT2DATE(date, time, "timezone")
date |
- |
Optional. A string or series of Julian integer dates, the input date. Defaults to the current date. |
time |
- |
Optional. A string or series of time of day values, the input time. Defaults to the current time. |
"timezone" |
- |
Optional. A string, the local time zone. Defaults to the current time zone. If specified, the resulting timestamps are based on UTC time. |
DT2DATE(datetime, "timezone")
datetime |
- |
An array, a datetime series where the date and time values are in adjacent columns. |
"timezone" |
- |
Optional. A string, the local time zone. Defaults to the current time zone. If specified, the resulting timestamps are based on UTC time. |
A series of fractional Julian date values.
W1: dt2date()
W1 contains a 1x1 series with the current date and time as fractional Julian date,
W2: dt2date("1/1/2024", "12:30:00")
W2 contains a 1x1 series with the following value:
{2460311.020833}
W2: dt2date("1/1/2024", "12:30:00")
W3: date2dt(w2)
Same as above except W3 converts the fractional Julian date value in W2 to a date time series. W3 contains the date time:
1/01/2024 12:30:00.000
W1: {{2030, 10, 30, 18, 0, 0},
{2030, 10, 31, 0, 0, 0},
{2030, 10, 31, 6, 0, 0},
{2030, 10, 31, 12, 0, 0}}
W2: ymdhms2dt(w1)
W3: dt2date(w2)
W4: date2dt(w3)
W1 contains raw date time values in year, month, date, hours, minutes, seconds format.
W2 converts the raw YMDHMS values in W1 to date time values. W2 contains the date times:
10/30/2030 18:00:00
10/31/2030 00:00:00
10/31/2030 06:00:00
10/31/2030 12:00:00
W3 converts the date time values of W2 into fractional Julian dates. W3 contains the values:
{2462805.25,
2462805.50,
2462805.75,
2462806.00}
W4 converts the fractional Julian date values in W3 to date time values. W4 contains the same date time values as W2:
10/30/2030 18:00:00
10/31/2030 00:00:00
10/31/2030 06:00:00
10/31/2030 12:00:00
DT2DATE converts a datetime series to fractional or astronomical Julian date values.
A datetime series consists of 2 columns of values where the first column contains integer Julian dates starting at midnight and the second column contains time in seconds starting from midnight.
A fractional Julian day is a real-valued count of days since January 1, 4713 BCE at noon UTC. The integer part represents the number of full days elapsed, while the fractional part represents the time of day, measured from noon, not midnight. For example, a fraction of 0.25 represents time 18:00:00 or 6 hours (one quarter of a day) after noon. The noon-based convention avoids discontinuities in astronomical observations that span midnight.
See DATE2DT to convert fractional Julian date values to date time values.
See YMDHMS2DT to convert a series of years, months, days, hours, minutes, seconds to a date time series.