PERF: some cython opts

Author: jreback

pandas/io/sas/sas7bdat.py

@@ -20,7 +20,7 @@
 import numpy as np
 import struct
 import pandas.io.sas.sas_constants as const
-from pandas.io.sas.saslib import do_read
+from pandas.io.sas.saslib import Parser
 
 
 class _subheader_pointer(object):
@@ -583,7 +583,8 @@ def read(self, nrows=None):
         self._byte_chunk = np.empty((nd, 8 * nrows), dtype=np.uint8)
 
         self._current_row_in_chunk_index = 0
-        do_read(self, nrows)
+        p = Parser(self)
+        p.read(nrows)
 
         rslt = self._chunk_to_dataframe()
         if self.index is not None: