Add function to replicate "ccb" slice flag

auxiliary_tools/cdat_regression_testing/759-slice-flag/prototype_ccb.py

@@ -0,0 +1,64 @@
+# %%
+import xcdat as xc
+
+# Parameters
+# Time coordinates at the first day of the month (1850-01-01)
+fn1 = "/global/cfs/cdirs/e3sm/e3sm_diags/test_model_data_for_acme_diags/time-series/E3SM_v1/FSNS_185001_201312.nc"
+var = "FSNS"
+start_time = "2011-01-15"
+end_time = "2013-12-15"
+
+slice_flag = "ccb"
+
+# %%
+ds_xcdat = xc.open_dataset(fn1, decode_times=True)
+
+ds_xcdat_s = ds_xcdat.sel(time=slice(start_time, end_time))
+
+# %%
+# 35 2013-12-01 00:00:00
+print(len(ds_xcdat_s.time), ds_xcdat_s.time.values[-1])
+
+# [cftime.DatetimeNoLeap(2013, 11, 1, 0, 0, 0, 0, has_year_zero=True)
+# cftime.DatetimeNoLeap(2013, 12, 1, 0, 0, 0, 0, has_year_zero=True)]
+print(ds_xcdat_s.time_bnds.values[-1])
+
+
+"""Possible solutions:
+1. Use last time coordinate (2014, 1, 1) with subsetting
+2. Use start value of the last bounds
+  - (2013, 12, 1), (2014, 1, 1)
+"""
+
+# 1. Get the last time coordinate as ds1
+# 2. Combine with ds2 (subsetted dataset)
+
+ds1 = ds_xcdat.isel(time=-1)
+
+# %%
+import xarray as xr
+
+ds_final = xr.concat([ds_xcdat_s, ds1], dim="time")
+
+# %%
+import cdms2
+import xcdat as xc
+
+# Parameters
+# Time coordinates at the first day of the month (1850-01-01)
+fn1 = "/global/cfs/cdirs/e3sm/e3sm_diags/test_model_data_for_acme_diags/time-series/E3SM_v1/FSNS_185001_201312.nc"
+var = "FSNS"
+start_time = "2011-01-15"
+end_time = "2013-12-15"
+
+slice_flag = "ccb"
+
+
+ds_cdat2 = cdms2.open(fn1)
+var_s = ds_cdat2(var, time=(start_time, end_time, slice_flag))(squeeze=1)
+
+# %%
+import numpy as np
+
+np.testing.assert_allclose(ds_final["FSNS"].values, var_s.data, rtol=0, atol=0)
+# %%

e3sm_diags/driver/utils/dataset_xr.py

@@ -979,8 +979,43 @@ def _get_time_series_dataset_obj(self, var) -> xr.Dataset:
         ds = xr.open_dataset(filepath, decode_times=True, use_cftime=True)
         ds_subset = ds.sel(time=time_slice).squeeze()
 
+        if not self.is_sub_monthly:
+            ds_subset = self._extend_time_for_non_submonthly_data(ds_subset)
+
         return ds_subset
 
+    def _extend_time_for_non_submonthly_data(self, ds: xr.Dataset) -> xr.Dataset:
+        """Extend the time coordinates for non-sub-monthly data.
+
+        This function replicates the cdms2/cdutil "ccb" slice flag used for
+        subsetting. "ccb" only allows the right side to be closed. It will use
+        bounds to determine the right bound value to add the coordinate point.
+
+        For example, with "2013-12-01" and "ccb":
+            1. Actual end time: "2013-12-01"
+            2. Slice end time: "2013-12-15"
+            3. Bound values: ["2013-12-01", "2014-1-1"]
+            4. Use "2014-1-1" as last coordinate point.
+
+        More info can be found in the API docstrings here: https://github.com/CDAT/cdms/blob/3f8c7baa359f428628a666652ecf361764dc7b7a/Lib/axis.py#L392-L414
+
+        Parameters
+        ----------
+        ds : xr.Dataset
+            The non-sub-monthly dataset.
+
+        Returns
+        -------
+        xr.Dataset
+            The non-sub-monthly dataset with an extra time coordinate point.12
+        """
+        time_dim = xc.get_dim_keys(ds, axis="T")
+
+        ds_last_time = ds.isel({time_dim: -1})
+        ds_final = xr.concat([ds, ds_last_time], dim=time_dim)
+
+        return ds_final
+
     def _get_timeseries_filepath(self, root_path: str, var_key: str) -> str:
         """Get the matching variable time series filepath.