Merge branch 'release/0.21.1'

climetlab/readers/netcdf/field.py

@@ -84,7 +84,7 @@ def to_bounding_box(self):
         )
 
     @cached_property
-    def projection(self):
+    def grid_mapping(self):
         def tidy(x):
             if isinstance(x, np.ndarray):
                 return x.tolist()
@@ -105,9 +105,6 @@ def tidy(x):
     def grid_points(self):
         return DataSet(self.owner.xr_dataset).grid_points(self.variable)
 
-    def grid_points_xy(self):
-        return DataSet(self.owner.xr_dataset).grid_points_xy(self.variable)
-
     def to_numpy(self, reshape=True, dtype=None):
         dimensions = dict((s.name, s.index) for s in self.slices)
         values = self.owner.xr_dataset[self.variable].isel(dimensions).values

climetlab/sources/constants.py

@@ -181,6 +181,37 @@ def cos_solar_zenith_angle(self, date):
         )
         return result.flatten()
 
+    def __getattr__(self, name):
+        if not "+" in name and not "-" in name:
+            # If we are here, we are looking for a method that does not exist,
+            # it has to be a method with a time delta.
+            raise AttributeError(name)
+        if "+" in name:
+            fname, delta = name.split("+")
+            sign = 1
+        if "-" in name:
+            fname, delta = name.split("-")
+            sign = -1
+        method = getattr(self, fname)
+
+        if delta.endswith("h"):
+            factor = 60
+        elif delta.endswith("d"):
+            factor = 24 * 60
+        else:
+            raise ValueError(f"Invalid time delta {delta} in {name}")
+
+        delta = delta[:-1]
+        delta = int(delta)
+        delta = datetime.timedelta(minutes=delta) * factor * sign
+
+        def wrapper(date):
+            date = date + delta
+            value = method(date)
+            return value
+
+        return wrapper
+
 
 class ConstantField:
     def __init__(

climetlab/version

@@ -1 +1 @@
-0.21.0
+0.21.1

tests/sources/test_constants.py

@@ -10,6 +10,7 @@
 #
 
 import datetime
+import numpy as np
 
 from climetlab import load_source
 from climetlab.testing import climetlab_file
@@ -86,6 +87,26 @@ def test_constant_2():
     assert len(ds) == len(params) * len(dates) * ntimes
 
 
+def test_constant_3():
+    sample = load_source("file", climetlab_file("docs/examples/test.grib"))
+
+    date = sample[0].datetime()
+    date_plus_6h = date + datetime.timedelta(hours=6)
+    a = load_source("constants", sample, date=date_plus_6h, param="insolation")
+    b = load_source("constants", sample, date=date, param="insolation+6h")
+    assert np.all(a.to_numpy() == b.to_numpy())
+    assert a.unique_values("param")["param"] == ("insolation",)
+    assert b.unique_values("param")["param"] == ("insolation+6h",)
+
+    date = sample[0].datetime()
+    date_minus_30d = date + datetime.timedelta(days=-30)
+    a = load_source("constants", sample, date=date_minus_30d, param="insolation")
+    b = load_source("constants", sample, date=date, param="insolation-30d")
+    assert np.all(a.to_numpy() == b.to_numpy())
+    assert a.unique_values("param")["param"] == ("insolation",)
+    assert b.unique_values("param")["param"] == ("insolation-30d",)
+
+
 if __name__ == "__main__":
     from climetlab.testing import main