implement TM5_subset in python

scripts/testdata-minimal/create_subsets_tm5.py

@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+from __future__ import annotations
+
+from pathlib import Path
+
+import xarray as xr
+
+from tests.fixtures.tm5 import TM5_DATA_PATH
+
+SRC_DATA_PATH = Path("/lustre/storeA/project/aerocom/aerocom-users-database")
+SRC_DATA_PATH /= "AEROCOM-PHASE-III-2019/TM5-met2010_AP3-CTRL2019/renamed"
+
+LON, LAT = slice(20, 30), slice(20, 30)
+
+PATHS = {
+    TM5_DATA_PATH / "aerocom3_TM5-met2010_AP3-CTRL2019_abs550aer_Column_2010_daily.nc",
+    TM5_DATA_PATH / "aerocom3_TM5-met2010_AP3-CTRL2019_od550aer_Column_2010_daily.nc",
+}
+
+
+def reduce_dims(ds: xr.Dataset) -> xr.Dataset:
+    """crop domain"""
+    return ds.isel(lon=LON, lat=LAT)
+
+
+def atomic_write(ds: xr.Dataset, path: Path, **kwargs) -> None:
+    """write dataset to a netcdf file atomically"""
+    tmp = path.with_suffix(".tmp")
+    try:
+        ds.to_netcdf(tmp, **kwargs)
+        tmp.rename(path)
+    finally:
+        tmp.unlink(missing_ok=True)
+
+
+def main():
+    for path in PATHS:
+        ds = xr.open_dataset(SRC_DATA_PATH / path.name).pipe(reduce_dims)
+        atomic_write(ds, path)
+
+
+if __name__ == "__main__":
+    main()