class numpy.lib.NumpyVersion(vstring)[source]

Parse and compare numpy version strings.

NumPy has the following versioning scheme (numbers given are examples; they can be > 9) in principle):

  • Released version: ‘1.8.0’, ‘1.8.1’, etc.

  • Alpha: ‘1.8.0a1’, ‘1.8.0a2’, etc.

  • Beta: ‘1.8.0b1’, ‘1.8.0b2’, etc.

  • Release candidates: ‘1.8.0rc1’, ‘1.8.0rc2’, etc.

  • Development versions: ‘’ (git commit hash appended)

  • Development versions after a1: ‘’,

    ‘’, ‘’, etc.

  • Development versions (no git hash available): ‘’

Comparing needs to be done against a valid version string or other NumpyVersion instance. Note that all development versions of the same (pre-)release compare equal.

New in version 1.9.0.


NumPy version string (np.__version__).


>>> from numpy.lib import NumpyVersion
>>> if NumpyVersion(np.__version__) < '1.7.0':
...     print('skip')
>>> # skip
>>> NumpyVersion('1.7')  # raises ValueError, add ".0"
Traceback (most recent call last):
ValueError: Not a valid numpy version string