Prepare 0.16.2 release (#5686)

* Prepare 0.16.2 release

This commit prepares for the 0.16.2 release by bumping the version
strings to reflect the new version. This is just a bugfix release
that several fixes for bugs introduced in 0.16.1.

* Mark DAGCircuit collect_1q_runs private

The collect_1q_runs method was rewritten in python as part of the
backport of a larger bugfix in the Optimize1qGatesDecomposition
transpiler pass in #5655. However, it is not part of the public api in
0.16.x and was only backported to fix the bug in
Optimize1qGatesDecomposition. Since the version included on the master
branch will be subtlely different in return type (after #5685) Since we
don't want to advertise the method until it's included in the public api
this commit prepends '_' making the method name _collect_1q_runs to
indicate it is internal only as part of the 0.16.2 release.

* Cleanup release notes

docs/conf.py

@@ -44,7 +44,7 @@
 # The short X.Y version
 version = ''
 # The full version, including alpha/beta/rc tags
-release = '0.16.1'
+release = '0.16.2'
 
 # -- General configuration ---------------------------------------------------
 

qiskit/VERSION.txt

@@ -1 +1 @@
-0.16.1
+0.16.2

qiskit/dagcircuit/dagcircuit.py

@@ -1422,7 +1422,7 @@ def collect_runs(self, namelist):
 
     # pylint: disable=too-many-boolean-expressions
 
-    def collect_1q_runs(self):
+    def _collect_1q_runs(self):
         """Return a set of non-conditional runs of 1q "op" nodes."""
         group_list = []
         # Iterate through the nodes of self in topological order

qiskit/transpiler/passes/optimization/optimize_1q_decomposition.py

@@ -68,7 +68,7 @@ def run(self, dag):
         if not self.basis:
             LOG.info("Skipping pass because no basis is set")
             return dag
-        runs = dag.collect_1q_runs()
+        runs = dag._collect_1q_runs()
         for run in runs:
             # Don't try to optimize a single 1q gate
             if len(run) <= 1:

releasenotes/notes/bugfix-assemble-delay-32a96b59bb84badd.yaml

@@ -1,9 +1,14 @@
 ---
 fixes:
   - |
-    Pulse :py:class:`~qiskit.pulse.instructions.Delay` is now explicitly
-    assembled as qobj instructions.
+    Pulse :py:class:`~qiskit.pulse.instructions.Delay` instructions are now
+    explicitly assembled as :class:`~qiskit.qobj.PulseQobjInstruction` objects
+    included in the :class:`~qiskit.qobj.PulseQobj` output from
+    :func:`~qiskit.compiler.assemble`.
 
-    Previously, we could ignore delays rather than assembling them. Now, with
-    pulse gates, there are times that we want to schedule ONLY a delay, and not
-    including the delay itself would remove the delay.
+    Previously, we could ignore :py:class:`~qiskit.pulse.instructions.Delay`
+    instructions in a :class:`~qiskit.pulse.Schedule` as part of
+    :func:`~qiskit.compiler.assemble` as the time was explicit in the
+    :class:`~qiskit.qobj.PulseQobj` objects. But, now with pulse gates, there
+    are situations where we can schedule ONLY a delay, and not including the
+    delay itself would remove the delay.

releasenotes/notes/fix-global-phase-upon-repeat-f742f4c0201fea97.yaml

@@ -1,8 +1,12 @@
 ---
 fixes:
   - |
-    Fix the global phase of the output of ``circuit.repeat``. If a circuit with global
-    phase is appended to another circuit, the global phase is currently not propagated.
-    The simulators rely on this, since the phase otherwise gets applied multiple times.
-    This sets the global phase of ``circuit.repeat`` to 0 instead of multiplying the existing
-    phase times the number of repetitions.
+    Fix the global phase of the output of the
+    :class:`~qiskit.circuit.QuantumCircuit` method
+    :meth:`~qiskit.circuit.QuantumCircuit.repeat`. If a circuit with global
+    phase is appended to another circuit, the global phase is currently not
+    propagated. Simulators rely on this, since the phase otherwise gets
+    applied multiple times. This sets the global phase of
+    :meth:`~qiskit.circuit.QuantumCircuit.repeat` to 0 before appending the
+    repeated circuit instead of multiplying the existing phase times the
+    number of repetitions.

releasenotes/notes/fix_hellinger_fidelity_def-7f60d53e3577fdaf.yaml

@@ -2,5 +2,6 @@
 fixes:
   - |
     The definition of the Hellinger fidelity from has been corrected from the
-    previous defition of :math`1-H(P,Q)` to :math:`[1-H(P,Q)**2]**2` so that it
-    is equal to the quantum state fidelity of P, Q as diagonal density matrices.
+    previous defition of :math:`1-H(P,Q)` to :math:`[1-H(P,Q)^2]^2` so that it
+    is equal to the quantum state fidelity of P, Q as diagonal density
+    matrices.

releasenotes/notes/transpile_singleton-61755c5cf1970111.yaml

@@ -4,7 +4,7 @@ fixes:
     When running :func:`qiskit.compiler.transpile` on a list of circuits with a
     single element, the function used to return a circuit instead of a list. Now,
     when :func:`qiskit.compiler.transpile` is called with a list, it will return a
-    list if when that list has a single element. See
+    list even if that list has a single element. See
     `#5260 <https://github.com/Qiskit/qiskit-terra/issues/5260>`__.
 
     .. code-block:: python
@@ -20,4 +20,4 @@ fixes:
       print(type(transpiled), len(transpiled))
 
     .. parsed-literal::
-     <class 'list'> 1
+     <class 'list'> 1

setup.py

@@ -77,7 +77,7 @@
 
 setup(
     name="qiskit-terra",
-    version="0.16.1",
+    version="0.16.2",
     description="Software for developing quantum computing programs",
     long_description=README,
     long_description_content_type='text/markdown',

test/python/dagcircuit/test_dagcircuit.py

@@ -718,7 +718,7 @@ def test_dag_collect_1q_runs(self):
         self.dag.apply_operation_back(CXGate(), [self.qubit2, self.qubit1])
         self.dag.apply_operation_back(CXGate(), [self.qubit1, self.qubit2])
         self.dag.apply_operation_back(HGate(), [self.qubit2])
-        collected_runs = self.dag.collect_1q_runs()
+        collected_runs = self.dag._collect_1q_runs()
         self.assertEqual(len(collected_runs), 2)
         for run in collected_runs:
             if run[0].name == 'h':
@@ -742,7 +742,7 @@ def test_dag_collect_1q_runs_start_with_conditional(self):
             h_gate, [self.qubit0])
         self.dag.apply_operation_back(HGate(), [self.qubit0])
         self.dag.apply_operation_back(HGate(), [self.qubit0])
-        collected_runs = self.dag.collect_1q_runs()
+        collected_runs = self.dag._collect_1q_runs()
         self.assertEqual(len(collected_runs), 1)
         run = collected_runs.pop()
         self.assertEqual(len(run), 2)
@@ -758,7 +758,7 @@ def test_dag_collect_1q_runs_conditional_in_middle(self):
         self.dag.apply_operation_back(
             h_gate, [self.qubit0])
         self.dag.apply_operation_back(HGate(), [self.qubit0])
-        collected_runs = self.dag.collect_1q_runs()
+        collected_runs = self.dag._collect_1q_runs()
         # Should return 2 single h gate runs (1 before condition, 1 after)
         self.assertEqual(len(collected_runs), 2)
         for run in collected_runs:
@@ -774,7 +774,7 @@ def test_dag_collect_1q_runs_with_parameterized_gate(self):
         self.dag.apply_operation_back(U1Gate(theta), [self.qubit0])
         self.dag.apply_operation_back(XGate(), [self.qubit0])
         self.dag.apply_operation_back(XGate(), [self.qubit0])
-        collected_runs = self.dag.collect_1q_runs()
+        collected_runs = self.dag._collect_1q_runs()
         self.assertEqual(len(collected_runs), 2)
         run_gates = [[x.name for x in run] for run in collected_runs]
         self.assertIn(['h', 'h'], run_gates)
@@ -794,7 +794,7 @@ def test_dag_collect_1q_runs_with_cx_in_middle(self):
         self.dag.apply_operation_back(YGate(), [self.qubit0])
         self.dag.apply_operation_back(XGate(), [self.qubit1])
         self.dag.apply_operation_back(XGate(), [self.qubit1])
-        collected_runs = self.dag.collect_1q_runs()
+        collected_runs = self.dag._collect_1q_runs()
         self.assertEqual(len(collected_runs), 4)
         for run in collected_runs:
             if run[0].name == 'h':