take ICON edge node connectivity from grid file (#927)

* take edge node connectivity from icon grid file Saves a lot of time when reading a big grid, as n_edge is used in _map_dims_to_ugrid, and will call _populate_edge_node_connectivity(self) if "edge_node_connectivity" is not defined. * update documentation. --------- Co-authored-by: Philip Chmielowiec <[email protected]>
UXARRAY · Sep 6, 2024 · ff9ec76 · ff9ec76
1 parent e50c879
commit ff9ec76
Show file tree

Hide file tree

Showing 2 changed files with 8 additions and 1 deletion.
diff --git a/docs/user-guide/grid-formats.rst b/docs/user-guide/grid-formats.rst
@@ -328,7 +328,7 @@ Connectivity
        <td class="no-cell">No</td>
        <td class="no-cell">No</td>
        <td class="no-cell">No</td>
-       <td class="no-cell">No</td>
+       <td class="yes-cell">Yes</td>
      </tr>
      <tr>
        <td>edge_edge</td>

diff --git a/uxarray/io/_icon.py b/uxarray/io/_icon.py
@@ -75,6 +75,13 @@ def _primal_to_ugrid(in_ds, out_ds):
         attrs=ugrid.EDGE_FACE_CONNECTIVITY_ATTRS,
     )
 
+    edge_node_connectivity = in_ds["edge_vertices"].T - 1
+    out_ds["edge_node_connectivity"] = xr.DataArray(
+        data=edge_node_connectivity,
+        dims=ugrid.EDGE_NODE_CONNECTIVITY_DIMS,
+        attrs=ugrid.EDGE_NODE_CONNECTIVITY_ATTRS,
+    )
+
     return out_ds, source_dims_dict