Resample NWP to half hourly. Closes #143

power_perceiver/transforms/nwp.py

@@ -0,0 +1,25 @@
+from dataclasses import dataclass
+from typing import Union
+
+import xarray as xr
+
+from power_perceiver.time import set_new_sample_period_and_t0_idx_attrs
+
+
+@dataclass
+class NWPInterpolate:
+    """Interpolate NWPs.
+
+    The xr.Dataset is modified in-place, and is returned.
+
+    Initialisation arguments:
+        freq:
+    """
+
+    freq: str = "30T"
+    kind: str = "cubic"
+
+    def __call__(self, xr_data: Union[xr.Dataset, xr.DataArray]) -> Union[xr.Dataset, xr.DataArray]:
+        xr_data = xr_data.resample(target_time_utc=self.freq).interpolate(kind=self.kind)
+        xr_data = set_new_sample_period_and_t0_idx_attrs(xr_data, new_sample_period=self.freq)
+        return xr_data