Adds cross-chi2 comparison script

cross_compare.py

@@ -0,0 +1,23 @@
+#!/usr/bin/env python3
+import sys
+import pickle
+
+from copycat import Problem
+from copycat.statistics import cross_chi_squared
+
+def compare_sets():
+    pass
+
+def main(args):
+    branchProblemSets = dict()
+    problemSets = []
+    for filename in args:
+        with open(filename, 'rb') as infile:
+            pSet = pickle.load(infile)
+            branchProblemSets[filename] = pSet
+            problemSets.append(pSet)
+    cross_chi_squared(problemSets)
+    return 0
+
+if __name__ == '__main__':
+    sys.exit(main(sys.argv[1:]))