Extract by time in iris

extract_by_time.py

"""Extract a cube slice using a time constraint."""
from datetime import datetime

import iris

# The cube with a time dimension
cube = mycubelist.extract_cube("some_variable")

# For example, we want to extract the time slice at 2020-04-29 12:00 model time,
# which corresponds to a time index of 123.
# Method 1.
time_constr = iris.Constraint(time=lambda t: t.point == datetime(2020, 4, 29, 12))

# Method 2.
tcoord = cube.coord("time")
time_constr = iris.Constraint(time=lambda t: t.point == tcoord.units.num2date(tcoord.points[123]))

# Extraction
cube_slice = cube.extract(time_constr)

# We can also extract several slices across the time dimension
dates = [tcoord.units.num2date(tcoord.points[i]) for i in [123, 234, 345]]  # or use an explicit list of datetime objects
cube.extract(iris.Constraint(time=lambda t: t.point in dates))