Pip: IOError : [Errno 13] Autorisation refusée : '/usr/local/bin/pip'

• Version du pip : 1.5.4
• Version Python : 2.7.6
• Système d'exploitation : Ubuntu 14.04

La description:

Comment puis-je résoudre le problème suivant :

J'essayais d'installer autograd et scikit-learn , tous deux via la commande pip. Cependant, les deux installations ont échoué, avec l'erreur
OSError: [Errno 13] Permission denied: '/usr/local/lib/python2.7/dist-packages/pip'

donc je suppose que ces erreurs peuvent être causées par pip, donc je teste pip avec la commande de mise à jour 'pip install -U pip', il a répondu
IOError: [Errno 13] Permission denied: '/usr/local/bin/pip'

Je suppose que le pip de ma machine est cassé? Tout conseil est très apprécié, merci.

Ce que j'ai couru :

Le journal de la commande en cours d'exécution 'pip install -U pip' répertorié ci-dessous :

Downloading/unpacking pip from https://pypi.python.org/packages/b6/ac/7015eb97dc749283ffdec1c3a88ddb8ae03b8fad0f0e611408f196358da3/pip-9.0.1-py2.py3-none-any.whl#md5=297dbd16ef53bcef0447d245815f5144
  Downloading pip-9.0.1-py2.py3-none-any.whl (1.3MB): 1.3MB downloaded
Installing collected packages: pip
  Found existing installation: pip 1.5.4
    Not uninstalling pip at /usr/lib/python2.7/dist-packages, owned by OS
  Can't roll back pip; was not uninstalled
Cleaning up...
Exception:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 122, in main
    status = self.run(options, args)
  File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 283, in run
    requirement_set.install(install_options, global_options, root=options.root_path)
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 1436, in install
    requirement.install(install_options, global_options, *args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 672, in install
    self.move_wheel_files(self.source_dir, root=root)
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 902, in move_wheel_files
    pycompile=self.pycompile,
  File "/usr/lib/python2.7/dist-packages/pip/wheel.py", line 312, in move_wheel_files
    generated.extend(maker.make(spec))
  File "/usr/share/python-wheels/distlib-0.1.8-py2.py3-none-any.whl/distlib/scripts.py", line 311, in make
    self._make_script(entry, filenames, options=options)
  File "/usr/share/python-wheels/distlib-0.1.8-py2.py3-none-any.whl/distlib/scripts.py", line 215, in _make_script
    self._write_script(scriptnames, shebang, script, filenames, ext)
  File "/usr/share/python-wheels/distlib-0.1.8-py2.py3-none-any.whl/distlib/scripts.py", line 195, in _write_script
    self._fileop.write_binary_file(outname, script_bytes)
  File "/usr/share/python-wheels/distlib-0.1.8-py2.py3-none-any.whl/distlib/util.py", line 384, in write_binary_file
    with open(path, 'wb') as f:
IOError: [Errno 13] Permission denied: '/usr/local/bin/pip'

Storing debug log for failure in /home/eric/.pip/pip.log