class_docstr: A uniform accessor that wraps data/schemas of varying formats with a
  common :func:`marshal` function.
docstr: For columnar datasets, return the :obj:`list`/Numpy array that
  contains the data for a single column.
  
  Args:
      name (:obj:`str`): the column name to look up
  
  Returns:
      (:obj:`list`/numpy.array/None): returns the column's data, or None
          if it cannot be found.
docstr_tok: ["For","columnar","datasets",",","return","the",":","obj",":","`","list","`","\/Numpy","array","that","contains","the","data","for","a","single","column",".","Args",":","name","(",":","obj",":","`","str","`",")",":","the","column","name","to","look","up","Returns",":","(",":","obj",":","`","list","`","\/numpy.array\/None",")",":","returns","the","column","'s","data",",","or","None","if","it","can","not","be","found","."]
code: def _get_numpy_column(self, name):
      """For columnar datasets, return the :obj:`list`/Numpy array that
      contains the data for a single column.
  
      Args:
          name (:obj:`str`): the column name to look up
  
      Returns:
          (:obj:`list`/numpy.array/None): returns the column's data, or None
              if it cannot be found.
      """
      data = self._data_or_schema.get(name, None)
      if data is None:
          raise PerspectiveError(
              "Column `{0}` does not exist.".format(name)
          )
      mask = self._numpy_column_masks.get(name, None)
      return deconstruct_numpy(data, mask)
  
imports: from distutils.util import strtobool
  from math import isnan
  import numpy
  import pandas
  from ..core.data import deconstruct_numpy, deconstruct_pandas, make_null_mask
  from ..core.data.pd import _parse_datetime_index
  from ..core.exception import PerspectiveError
  from ._date_validator import _PerspectiveDateValidator
  from .libpsppy import t_dtype
label_desc: Use image node_id 11 for calling the _PerspectiveAccessor obj's underlying member method code with example usage: obj._get_numpy_column(name) and returns: deconstruct_numpy