def available_backends(filters=None, compact=True):
"""
Return names of backends that are available in the SDK, optionally filtering
them based on their capabilities.
Note:
In order for this function to return online backends, a connection with
an online backend provider needs to be established by calling the
`register()` function.
Note:
If two or more providers have backends with the same name, those names
will be shown only once. To disambiguate and choose a backend from a
specific provider, get the backend from that specific provider.
Example::
p1 = register(token1)
p2 = register(token2)
execute(circuit, p1.get_backend('ibmq_5_tenerife'))
execute(circuit, p2.get_backend('ibmq_5_tenerife'))
Args:
filters (dict or callable): filtering conditions.
compact (bool): group backend names based on compact group names.
Returns:
list[str]: the names of the available backends.
.. deprecated:: 0.6+
After 0.6, this function is deprecated. Please use the methods in
`qiskit.IBMQ` and `qiskit.backends.local.Aer` instead
(`backends()`).
"""
warnings.warn(
'available_backends() will be deprecated after 0.6. Please '
'use the qiskit.IBMQ.backends() and qiskit.Aer.backends() '
'method instead.', DeprecationWarning)
if isinstance(filters, dict):
kwargs = filters
else:
kwargs = {'filters': filters}
ibmq_names = [backend.name() for backend in IBMQ.backends(**kwargs)]
aer_names = [backend.name() for backend in Aer.backends(**kwargs)]
if compact:
# Hack for backwards compatibility: reverse the groups for local.
aer_groups = Aer.grouped_backend_names()
reversed_aer_groups = {}
for group, items in aer_groups.items():
for alias in items:
reversed_aer_groups[alias] = group
aer_names = list(set(reversed_aer_groups[name] for name in aer_names))
return ibmq_names + aer_names
def test_groups(self):
"""Test that aggregate group names map to the first available backend
of their list of backends."""
aer_groups = Aer.grouped_backend_names()
for group_name, priority_list in aer_groups.items():
with self.subTest(group_name=group_name,
priority_list=priority_list):
target_backend = _get_first_available_backend(priority_list)
if target_backend:
self.assertEqual(Aer.get_backend(group_name),
Aer.get_backend(target_backend))
