text: from common import *
  import collections
  import numpy as np
  
  def test_astype(ds_local):
      ds = ds_local
      ds_original = ds.copy()
      #ds.columns['x'] = (ds.columns['x']*1).copy()  # convert non non-big endian for now
      ds['x'] = ds['x'].astype('f4')
  
      assert ds.x.evaluate().dtype == np.float32
      assert ds.x.tolist() == ds_original.x.evaluate().astype(np.float32).tolist()
  