Experimenting with Zarr chunking

zarr-chunks.py

import xarray as xr
import numpy as np

d1 = np.random.rand(133, 10, 10)
t1 = np.arange(1, 134)
xs = np.arange(1, 11)
ys = np.arange(1, 11)

chunking = {"time": 100, "x": 10, "y": 10}

dat1 = xr.Dataset(
    {"data": (["time", "x", "y"], d1)},
    coords = {"time": t1}
)#.chunk(chunking)

dat1.to_zarr("test_1.zarr", mode="w")
dat1.to_zarr("test_append.zarr", mode="w")

dat1z = xr.open_zarr("test_1.zarr")

d2 = np.random.rand(3, 10, 10)
t2 = np.arange(np.max(t1)+1, np.max(t1)+1+d2.shape[0])
dat2 = xr.Dataset(
    {"data": (["time", "x", "y"], d2)},
    coords = {"time": t2}
).chunk({"time": 3})

dat2.to_zarr("test_append.zarr", mode="a", append_dim="time")

d3 = np.random.rand(15, 10, 10)
t3 = np.arange(np.max(t2)+1, np.max(t2)+1+d3.shape[0])
dat3 = xr.Dataset(
    {"data": (["time", "x", "y"], d3)},
    coords = {"time": t3}
).chunk({"time": 15})

dat3.to_zarr("test_append.zarr", mode="a", append_dim="time")

dat_123 = xr.open_zarr("test_append.zarr")
dat_123.chunks

dat_combined = xr.concat((dat1z, dat2, dat3), dim="time")
dat_combined.to_zarr("test_combined.zarr", mode="w", safe_chunks=False)

dat_combinedz = xr.open_zarr("test_combined.zarr")
dat_combinedz.chunks