Fixed bug for inserting to back of Dataframe (#116)

* fixed bug for inserting to back of dataframe

* removed unused import

modin/data_management/data_manager.py

@@ -8,7 +8,6 @@
 from pandas.compat import string_types
 from pandas.core.dtypes.cast import find_common_type
 from pandas.core.dtypes.common import (
-    _get_dtype_from_object,
     is_list_like,
     is_numeric_dtype,
     is_datetime_or_timedelta_dtype,
@@ -2056,13 +2055,7 @@ def insert(df, internal_indices=[]):
         )
         new_columns = self.columns.insert(loc, column)
 
-        # Because a Pandas Series does not allow insert, we make a DataFrame
-        # and insert the new dtype that way.
-        temp_dtypes = pandas.DataFrame(self.dtypes).T
-        temp_dtypes.insert(loc, column, _get_dtype_from_object(value))
-        new_dtypes = temp_dtypes.iloc[0]
-
-        return self.__constructor__(new_data, self.index, new_columns, new_dtypes)
+        return self.__constructor__(new_data, self.index, new_columns)
 
     # END Insert
 

modin/data_management/partitioning/partition_collections.py

@@ -510,6 +510,8 @@ def _get_blocks_containing_index(self, axis, index):
         if not axis:
             cumulative_column_widths = np.array(self.block_widths).cumsum()
             block_idx = int(np.digitize(index, cumulative_column_widths))
+            if block_idx == len(cumulative_column_widths):
+                block_idx -= 1
             # Compute the internal index based on the previous lengths. This
             # is a global index, so we must subtract the lengths first.
             internal_idx = (