Adds function to concatenate runs along trainId dimension

Concatenate a list of runs and sort by trainId

2019-10-22_Concatenate_runs.pdf

2019-10-22_Concatenate_runs.ipynb

Load.py

@@ -451,15 +451,17 @@ def load(fields, runNB, proposalNB, semesterNB, topic='SCS', display=False,
     return result
 
 def concatenateRuns(runs):
-    """ Concatenate two runs with identical data variables along the trainId dimension
+    """ Concatenate a list of two runs with identical data variables along the
+        trainId dimension.
+        
         Input:
             runs: (list) the xarray Datasets to concatenate
         Output:
             a concatenated xarray Dataset
     """
-    keys = runs[0].keys()
+    keys = sorted(runs[0].keys())
     for run in runs[1:]:
-        if run.keys() != keys:
+        if sorted(run.keys()) != keys:
             print('data fields between different runs are not identical. Cannot combine runs.')
             return