Convert DEM to dask array.

climax/core/dataset.py

@@ -142,7 +142,9 @@ class EoDataset(torch.utils.data.Dataset):
             alg='Horn').ReadAsArray().astype(np.float32)
 
         # read digital elevation model
-        dem = img2np(dem).astype(np.float32)
+        dem = da.asarray(img2np(dem).astype(np.float32))
+        slope = da.asarray(slope)
+        aspect = da.asarray(aspect)
 
         # digital elevation model features: elevation, slope and aspect
         dem_vars = {