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Co-authored-by: Illviljan <14371165+Illviljan@users.noreply.github.com>

xarray/core/dataset.py

@@ -2925,7 +2925,7 @@ def _validate_interp_indexers(
             elif is_scalar(v):
                 yield k, Variable((), v, attrs=self.coords[k].attrs)
             elif isinstance(v, np.ndarray):
-                yield k, Variable(dims=(k,), data=v, attrs=self.coords[k].attrs)
+                yield k, Variable(dims=(k,), data=v, attrs=self.coords[k].attrs, fastpath=True)
             else:
                 raise TypeError(type(v))