TimeConverter.reltime with time_origin = np.timedelta64 sensitive to precision #1738
Description
Parcels version
master
Description
The internals of TimeConverter with np.timedelta64 assumes that the precision is in seconds, when that might not actually be the case. Hence np.timedelta64(1, "D") - 1 gives 0 when in reality it should be treated in seconds all the way.
What would be a suitable precision for the object? I assume nanoseconds and then convert to float seconds for output?
Code sample
import cftime
import numpy as np
from parcels.tools.converters import TimeConverter, _get_cftime_datetimes
DAY = 24 * 60 * 60
def test_TimeConverter_timedelta64_float():
tc = TimeConverter(np.timedelta64(0, "s"))
assert tc.reltime(1 * DAY) == 1 * DAY
tc = TimeConverter(np.timedelta64(0, "D"))
assert tc.reltime(1 * DAY) == 1 * DAY________________________________________________ test_TimeConverter_timedelta64_float _________________________________________________
def test_TimeConverter_timedelta64_float():
tc = TimeConverter(np.timedelta64(0, "s"))
assert tc.reltime(1 * DAY) == 1 * DAY
tc = TimeConverter(np.timedelta64(0, "D"))
> assert tc.reltime(1 * DAY) == 1 * DAY
E assert np.float64(7464960000.0) == (1 * 86400)
E + where np.float64(7464960000.0) = reltime((1 * 86400))
E + where reltime = 0 days.reltime
tests/tools/test_converters.py:24: AssertionError
======================================================= short test summary info =======================================================
FAILED tests/tools/test_converters.py::test_TimeConverter_timedelta64_float - assert np.float64(7464960000.0) == (1 * 86400)