TST: vb for Index.intersection/union

Author: wesm

pandas/src/internals.pyx

@@ -0,0 +1,13 @@
+def get_reverse_indexer(ndarray[int32_t] indexer, Py_ssize_t length):
+    cdef:
+        Py_ssize_t i
+        ndarray[int32_t] rev_indexer
+        int32_t idx
+
+    rev_indexer = np.empty(length, dtype='i4')
+    for i in range(len(indexer)):
+        idx = indexer[i]
+        if idx != -1:
+            rev_indexer[idx] = i
+
+    return rev_indexer

vb_suite/index_object.py

@@ -3,3 +3,20 @@
 
 SECTION = "Index / MultiIndex objects"
 
+
+common_setup = """from pandas_vb_common import *
+"""
+
+#----------------------------------------------------------------------
+# intersection, union
+
+setup = common_setup + """
+rng = DateRange('1/1/2000', periods=10000, offset=datetools.Minute())
+rng = rng.view(Index)
+rng2 = rng[:-1]
+"""
+
+index_datetime_intersection = Benchmark("rng.intersection(rng2)", setup,
+                                        name='index_datetime_intersection')
+index_datetime_union = Benchmark("rng.union(rng2)", setup,
+                                 name='index_datetime_union')