xorbits.numpy.fromregex#

xorbits.numpy.fromregex(file, regexp, dtype, encoding=None)#

Construct an array from a text file, using regular expression parsing.

The returned array is always a structured array, and is constructed from all matches of the regular expression in the file. Groups in the regular expression are converted to fields of the structured array.

参数

  • file (path or file) –

    Filename or file object to read.

    在 1.22.0(numpy) 版更改: Now accepts os.PathLike implementations.

  • regexp (str or regexp) – Regular expression used to parse the file. Groups in the regular expression correspond to fields in the dtype.

  • dtype (dtype or list of dtypes) – Dtype for the structured array; must be a structured datatype.

  • encoding (str, optional) –

    Encoding used to decode the inputfile. Does not apply to input streams.

    1.14.0(numpy) 新版功能.

返回

output – The output array, containing the part of the content of file that was matched by regexp. output is always a structured array.

返回类型

ndarray

引发

TypeError – When dtype is not a valid dtype for a structured array.

参见

fromstring, loadtxt

提示

Dtypes for structured arrays can be specified in several forms, but all forms specify at least the data type and field name. For details see basics.rec.

实际案例

>>> from io import StringIO  
>>> text = StringIO("1312 foo\n1534  bar\n444   qux")  

>>> regexp = r"(\d+)\s+(...)"  # match [digits, whitespace, anything]  
>>> output = np.fromregex(text, regexp,  
...                       [('num', np.int64), ('key', 'S3')])
>>> output  
array([(1312, b'foo'), (1534, b'bar'), ( 444, b'qux')],
      dtype=[('num', '<i8'), ('key', 'S3')])
>>> output['num']  
array([1312, 1534,  444])

警告

This method has not been implemented yet. Xorbits will try to execute it with numpy.

This docstring was copied from numpy.