Fix concatenation of datasets when some are empty (#123)

Author: smithara

docs/release_notes.rst

@@ -4,6 +4,12 @@ Release notes
 Change log
 ----------
 
+Changes from 0.12.2 to 0.12.3
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+- Added support for Swarm FAST TEC ``SW_FAST_TECxTMS_2F`` products.
+- Fixed error when loading some chunked data with xarray, when one of the chunks has zero length
+
 Changes from 0.12.1 to 0.12.2
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 

src/viresclient/__init__.py

@@ -35,4 +35,4 @@
 from ._config import ClientConfig, set_token
 from ._data_handling import ReturnedData, ReturnedDataFile
 
-__version__ = "0.12.2"
+__version__ = "0.12.3"

src/viresclient/_data_handling.py

@@ -783,7 +783,11 @@ def as_dataframe(self, expand=False):
             pandas.DataFrame
 
         """
-        return pandas.concat([d.as_dataframe(expand=expand) for d in self.contents])
+        dataframes = [data.as_dataframe(expand=expand) for data in self.contents]
+        if len(dataframes) > 1:
+            return pandas.concat([df for df in dataframes if not df.empty])
+        else:
+            return dataframes[0]
 
     def as_xarray(self, reshape=False):
         """Convert the data to an xarray Dataset.
@@ -821,6 +825,8 @@ def as_xarray(self, reshape=False):
         elif self._time_variable in ds_list[0].dims:
             # Address simpler concatenation case for VirES for Swarm
             # Timestamp always exists for Swarm, but is not present in Aeolus
+            # Remove datasets of length 0 so that concatenation works
+            ds_list = [ds for ds in ds_list if ds[self._time_variable].size != 0]
             ds = xarray.concat(ds_list, dim=self._time_variable)
         else:
             # Address complex concatenation case for VirES for Aeolus