Fixturize and clean imports for test_arithmetic

Author: h-vetinari

Diff for: pandas/tests/frame/conftest.py

@@ -82,9 +82,10 @@ def mixed_float_frame():
     Columns are ['A', 'B', 'C', 'D'].
     """
     df = DataFrame(tm.getSeriesData())
-    df.A = df.A.astype('float16')
+    df.A = df.A.astype('float32')
     df.B = df.B.astype('float32')
-    df.C = df.C.astype('float64')
+    df.C = df.C.astype('float16')
+    df.D = df.D.astype('float64')
     return df
 
 
@@ -96,9 +97,10 @@ def mixed_float_frame2():
     Columns are ['A', 'B', 'C', 'D'].
     """
     df = DataFrame(tm.getSeriesData())
-    df.D = df.D.astype('float16')
+    df.D = df.D.astype('float32')
     df.C = df.C.astype('float32')
-    df.B = df.B.astype('float64')
+    df.B = df.B.astype('float16')
+    df.D = df.D.astype('float64')
     return df
 
 
@@ -111,10 +113,10 @@ def mixed_int_frame():
     """
     df = DataFrame({k: v.astype(int)
                    for k, v in compat.iteritems(tm.getSeriesData())})
-    df.A = df.A.astype('uint8')
-    df.B = df.B.astype('int32')
-    df.C = df.C.astype('int64')
-    df.D = np.ones(len(df.D), dtype='uint64')
+    df.A = df.A.astype('int32')
+    df.B = np.ones(len(df.B), dtype='uint64')
+    df.C = df.C.astype('uint8')
+    df.D = df.C.astype('int64')
     return df