numpy.format_parser¶
- class numpy.format_parser(formats, names, titles, aligned=False, byteorder=None)[source]¶
Class to convert formats, names, titles description to a dtype.
After constructing the format_parser object, the dtype attribute is the converted data-type:
dtype = format_parser(formats, names, titles).dtype- Parameters
- formatsstr or list of str
The format description, either specified as a string with comma-separated format descriptions in the form
'f8, i4, a5', or a list of format description strings in the form['f8', 'i4', 'a5'].- namesstr or list/tuple of str
The field names, either specified as a comma-separated string in the form
'col1, col2, col3', or as a list or tuple of strings in the form['col1', 'col2', 'col3']. An empty list can be used, in that case default field names (‘f0’, ‘f1’, …) are used.- titlessequence
Sequence of title strings. An empty list can be used to leave titles out.
- alignedbool, optional
If True, align the fields by padding as the C-compiler would. Default is False.
- byteorderstr, optional
If specified, all the fields will be changed to the provided byte-order. Otherwise, the default byte-order is used. For all available string specifiers, see
dtype.newbyteorder.
See also
Examples
>>> np.format_parser(['<f8', '<i4', '<a5'], ['col1', 'col2', 'col3'], ... ['T1', 'T2', 'T3']).dtype dtype([(('T1', 'col1'), '<f8'), (('T2', 'col2'), '<i4'), (('T3', 'col3'), 'S5')])
names and/or titles can be empty lists. If titles is an empty list, titles will simply not appear. If names is empty, default field names will be used.
>>> np.format_parser(['f8', 'i4', 'a5'], ['col1', 'col2', 'col3'], ... []).dtype dtype([('col1', '<f8'), ('col2', '<i4'), ('col3', '<S5')]) >>> np.format_parser(['<f8', '<i4', '<a5'], [], []).dtype dtype([('f0', '<f8'), ('f1', '<i4'), ('f2', 'S5')])
- Attributes
- dtypedtype
The converted data-type.