toqito.channel_metrics.completely_bounded_spectral_norm
=======================================================

.. py:module:: toqito.channel_metrics.completely_bounded_spectral_norm

.. autoapi-nested-parse::

   Computes the completely bounded spectral norm of a quantum channel.





Module Contents
---------------

.. py:function:: completely_bounded_spectral_norm(phi)

   Compute the completely bounded spectral norm of a quantum channel.

   As defined in [@Watrous_2009_Semidefinite] and [@QETLAB_link].

   .. rubric:: Examples

   To compute the completely bounded spectral norm of a depolarizing channel:

   ```python exec="1" source="above"
   from toqito.channels import depolarizing
   from toqito.channel_metrics import completely_bounded_spectral_norm
   # Define the depolarizing channel
   choi_depolarizing = depolarizing(dim=2, param_p=0.2)
   print(completely_bounded_spectral_norm(choi_depolarizing))
   ```

   :param phi: superoperator

   :returns: The completely bounded spectral norm of the channel