Note open_dataset, mfdataset open files as read-only (closes pydata#2345

).
dcherian · Mar 7, 2019 · 83f92ac · 83f92ac
1 parent e5c04dc
commit 83f92ac
Showing 1 changed file with 14 additions and 0 deletions.
diff --git a/xarray/backends/api.py b/xarray/backends/api.py
@@ -247,6 +247,13 @@ def open_dataset(filename_or_obj, group=None, decode_cf=True,
     dataset : Dataset
         The newly created dataset.
 
+    Notes
+    -----
+    ``open_dataset`` opens the file with read-only access. When you modify
+    values of a Dataset, even one linked to files on disk, only the in-memory
+    copy you are manipulating in xarray is modified: the original file on disk
+    is never touched.
+
     See Also
     --------
     open_mfdataset
@@ -597,6 +604,13 @@ def open_mfdataset(paths, chunks=None, concat_dim=_CONCAT_DIM_DEFAULT,
     -------
     xarray.Dataset
 
+    Notes
+    -----
+    ``open_mfdataset`` opens files with read-only access. When you modify values
+    of a Dataset, even one linked to files on disk, only the in-memory copy you
+    are manipulating in xarray is modified: the original file on disk is never
+    touched.
+
     See Also
     --------
     auto_combine