def get_counts(self, experiment=None):
"""Get the histogram data of an experiment.
Args:
experiment (str or QuantumCircuit or Schedule or int or None): the index of the
experiment, as specified by ``get_data()``.
Returns:
dict[str:int]: a dictionary with the counts for each qubit, with
the keys containing a string in binary format and separated
according to the registers in circuit (e.g. ``0100 1110``).
The string is little-endian (cr[0] on the right hand side).
Raises:
QiskitError: if there are no counts for the experiment.
"""
exp = self._get_experiment(experiment)
try:
header = exp.header.to_dict()
except (AttributeError, QiskitError): # header is not available
header = None
if 'counts' in self.data(experiment).keys():
return postprocess.format_counts(
self.data(experiment)['counts'], header)
elif 'statevector' in self.data(experiment).keys():
vec = postprocess.format_statevector(
self.data(experiment)['statevector'])
return state_to_counts(vec)
else:
raise QiskitError(
'No counts for experiment "{0}"'.format(experiment))
def test_state_to_counts(self):
"""Test statevector to counts"""
qc = QuantumCircuit(5)
qc.h(2)
qc.cx(2, 1)
qc.cx(1, 0)
qc.cx(2, 3)
qc.cx(3, 4)
sim = BasicAer.get_backend('statevector_simulator')
res = execute(qc, sim).result()
vec = res.get_statevector()
counts = state_to_counts(vec)
self.assertAlmostEqual(counts['00000'], 0.5)
self.assertAlmostEqual(counts['11111'], 0.5)
def get_counts(self, experiment=None):
"""Get the histogram data of an experiment.
Args:
experiment (str or QuantumCircuit or Schedule or int or None): the index of the
experiment, as specified by ``get_data()``.
Returns:
dict[str:int] or list[dict[str:int]]: a dictionary or a list of
dictionaries. A dictionary has the counts for each qubit with
the keys containing a string in binary format and separated
according to the registers in circuit (e.g. ``0100 1110``).
The string is little-endian (cr[0] on the right hand side).
Raises:
QiskitError: if there are no counts for the experiment.
"""
if experiment is None:
exp_keys = range(len(self.results))
else:
exp_keys = [experiment]
dict_list = []
for key in exp_keys:
exp = self._get_experiment(key)
try:
header = exp.header.to_dict()
except (AttributeError, QiskitError): # header is not available
header = None
if 'counts' in self.data(key).keys():
dict_list.append(postprocess.format_counts(self.data(key)['counts'], header))
elif 'statevector' in self.data(key).keys():
vec = postprocess.format_statevector(self.data(key)['statevector'])
dict_list.append(state_to_counts(vec))
else:
raise QiskitError('No counts for experiment "{0}"'.format(key))
# Return first item of dict_list if size is 1
if len(dict_list) == 1:
return dict_list[0]
else:
return dict_list