Fix #81

Author: chrisburr

root_pandas/readwrite.py

@@ -95,11 +95,11 @@ def get_nonscalar_columns(array):
 def get_matching_variables(branches, patterns, fail=True):
     # Convert branches to a set to make x "in branches" O(1) on average
     branches = set(branches)
-    patterns = set(patterns)
     # Find any trivial matches
-    selected = list(branches.intersection(patterns))
+    selected = sorted(branches.intersection(patterns),
+                      key=lambda s: patterns.index(s))
     # Any matches that weren't trivial need to be looped over...
-    for pattern in patterns.difference(selected):
+    for pattern in set(patterns).difference(selected):
         found = False
         # Avoid using fnmatch if the pattern if possible
         if re.findall(r'(\*)|(\?)|(\[.*\])|(\[\!.*\])', pattern):