Add ShiftFrequency instruction to pulse (#4390)

* Add ShiftFrequency

* Review suggestions

* Lint

* remove unwanted newlines

* lint

* add newline

* Review suggestions and bugfix

* Reno

* Hz -> GHz conversion for ShiftFrequency -> PulseQobjInstruction

* Logic fixes

* review suggestion

* review suggestions

Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

qiskit/pulse/__init__.py

@@ -137,7 +137,8 @@ from .commands import AcquireInstruction, FrameChange, PersistentValue
 from .configuration import LoConfig, LoRange, Kernel, Discriminator
 from .exceptions import PulseError
 from .instruction_schedule_map import InstructionScheduleMap
-from .instructions import Acquire, Instruction, Delay, Play, ShiftPhase, Snapshot, SetFrequency
+from .instructions import (Acquire, Instruction, Delay, Play, ShiftPhase, Snapshot,
+                           SetFrequency, ShiftFrequency)
 from .interfaces import ScheduleComponent
 from .pulse_lib import (SamplePulse, Gaussian, GaussianSquare, Drag,
                         Constant, ConstantPulse, ParametricPulse)

qiskit/pulse/instructions/__init__.py

@@ -39,6 +39,7 @@ sequence of scheduled Pulse ``Instruction`` s over many channels. ``Instruction`
    Delay
    Play
    SetFrequency
+   ShiftFrequency
    ShiftPhase
    Snapshot
 
@@ -53,7 +54,7 @@ Abstract Classes
 from .acquire import Acquire
 from .delay import Delay
 from .instruction import Instruction
-from .frequency import SetFrequency
+from .frequency import SetFrequency, ShiftFrequency
 from .phase import ShiftPhase
 from .play import Play
 from .snapshot import Snapshot

qiskit/pulse/instructions/frequency.py

@@ -60,3 +60,34 @@ class SetFrequency(Instruction):
         scheduled on.
         """
         return self._channel
+
+
+class ShiftFrequency(Instruction):
+    """Shift the channel frequency away from the current frequency."""
+
+    def __init__(self,
+                 frequency: float,
+                 channel: PulseChannel,
+                 name: Optional[str] = None):
+        """Creates a new shift frequency instruction.
+
+        Args:
+            frequency: Frequency shift of the channel in Hz.
+            channel: The channel this instruction operates on.
+            name: Name of this set channel frequency command.
+        """
+        self._frequency = float(frequency)
+        self._channel = channel
+        super().__init__((frequency, channel), 0, (channel,), name=name)
+
+    @property
+    def frequency(self) -> float:
+        """Frequency shift from the set frequency."""
+        return self._frequency
+
+    @property
+    def channel(self) -> PulseChannel:
+        """Return the :py:class:`~qiskit.pulse.channels.Channel` that this instruction is
+        scheduled on.
+        """
+        return self._channel

qiskit/qobj/converters/pulse_instruction.py

@@ -273,6 +273,25 @@ class InstructionToQobjConverter:
         }
         return self._qobj_model(**command_dict)
 
+    @bind_instruction(instructions.ShiftFrequency)
+    def convert_shift_frequency(self, shift, instruction):
+        """Return converted `ShiftFrequency`.
+
+        Args:
+            shift (int): Offset time.
+            instruction (ShiftFrequency): Shift frequency instruction.
+
+        Returns:
+            dict: Dictionary of required parameters.
+        """
+        command_dict = {
+            'name': 'shiftf',
+            't0': shift+instruction.start_time,
+            'ch': instruction.channel.name,
+            'frequency': instruction.frequency / 1e9
+        }
+        return self._qobj_model(**command_dict)
+
     @bind_instruction(instructions.ShiftPhase)
     def convert_shift_phase(self, shift, instruction):
         """Return converted `ShiftPhase`.
@@ -545,6 +564,31 @@ class QobjToInstructionConverter:
 
         return instructions.SetFrequency(frequency, channel) << t0
 
+    @bind_name('shiftf')
+    def convert_shift_frequency(self, instruction):
+        """Return converted `ShiftFrequency`.
+
+        Args:
+            instruction (PulseQobjInstruction): Shift frequency qobj instruction.
+
+        Returns:
+            Schedule: Converted and scheduled Instruction
+        """
+        t0 = instruction.t0
+        channel = self.get_channel(instruction.ch)
+        frequency = instruction.frequency * 1e9
+
+        if isinstance(frequency, str):
+            frequency_expr = parse_string_expr(frequency, partial_binding=False)
+
+            def gen_sf_schedule(*args, **kwargs):
+                _frequency = frequency_expr(*args, **kwargs)
+                return instructions.ShiftFrequency(_frequency, channel) << t0
+
+            return ParameterizedSchedule(gen_sf_schedule, parameters=frequency_expr.params)
+
+        return instructions.ShiftFrequency(frequency, channel) << t0
+
     @bind_name('delay')
     def convert_delay(self, instruction):
         """Return converted `Delay`.

qiskit/visualization/pulse/matplotlib.py

@@ -36,7 +36,7 @@ from qiskit.pulse.channels import (DriveChannel, ControlChannel,
 from qiskit.pulse.commands import FrameChangeInstruction
 from qiskit.pulse import (SamplePulse, FrameChange, PersistentValue, Snapshot, Play,
                           Acquire, PulseError, ParametricPulse, SetFrequency, ShiftPhase,
-                          Instruction, ScheduleComponent)
+                          Instruction, ScheduleComponent, ShiftFrequency)
 
 
 class EventsOutputChannels:
@@ -105,6 +105,14 @@ class EventsOutputChannels:
 
         return self._trim(self._frequencychanges)
 
+    @property
+    def frequencyshift(self) -> Dict[int, ShiftFrequency]:
+        """Set the frequency changes."""
+        if self._frequencychanges is None:
+            self._build_waveform()
+
+        return self._trim(self._frequencychanges)
+
     @property
     def conditionals(self) -> Dict[int, str]:
         """Get conditionals."""
@@ -194,6 +202,8 @@ class EventsOutputChannels:
                     pv[time:] = 0
                 elif isinstance(command, SetFrequency):
                     tmp_sf = command.frequency
+                elif isinstance(command, ShiftFrequency):
+                    tmp_sf = command.frequency
                 elif isinstance(command, Snapshot):
                     self._snapshots[time] = command.name
             if tmp_fc != 0:

releasenotes/notes/implement-shift-frequency-46d4ea16d8be2f58.yaml

@@ -0,0 +1,10 @@
+---
+features:
+  - |
+    The :py:class:`~qiskit.pulse.instructions.ShiftFrequency` instruction allows users
+    to shift the frequency from the set frequency. For example::
+
+       sched += ShiftFrequency(-340e6, DriveChannel(0))
+
+    In this example, all the pulses applied to ``DriveChannel(0)`` after the
+    ``ShiftFrequency`` command will have the envelope a frequency decremented by 340MHz.

test/python/pulse/test_schedule.py

@@ -20,7 +20,7 @@ import numpy as np
 
 from qiskit.pulse import (Play, SamplePulse, ShiftPhase, Instruction, SetFrequency, Acquire,
                           pulse_lib, Snapshot, Delay, Gaussian, Drag, GaussianSquare, Constant,
-                          functional_pulse)
+                          functional_pulse, ShiftFrequency)
 from qiskit.pulse.channels import (MemorySlot, RegisterSlot, DriveChannel, AcquireChannel,
                                    SnapshotChannel, MeasureChannel)
 from qiskit.pulse.commands import PersistentValue, PulseInstruction
@@ -665,6 +665,7 @@ class TestScheduleFilter(BaseTestSchedule):
         sched = sched.insert(10, Play(lp0, self.config.drive(1)))
         sched = sched.insert(30, ShiftPhase(-1.57, self.config.drive(0)))
         sched = sched.insert(40, SetFrequency(8.0, self.config.drive(0)))
+        sched = sched.insert(50, ShiftFrequency(4.0e6, self.config.drive(0)))
         for i in range(2):
             sched = sched.insert(60, Acquire(5, self.config.acquire(i), MemorySlot(i)))
         sched = sched.insert(90, Play(lp0, self.config.drive(0)))
@@ -686,22 +687,30 @@ class TestScheduleFilter(BaseTestSchedule):
         for _, inst in no_pulse_and_fc.instructions:
             self.assertFalse(isinstance(inst, (Play, ShiftPhase)))
         self.assertEqual(len(only_pulse_and_fc.instructions), 4)
-        self.assertEqual(len(no_pulse_and_fc.instructions), 3)
+        self.assertEqual(len(no_pulse_and_fc.instructions), 4)
 
         # test on ShiftPhase
         only_fc, no_fc = \
             self._filter_and_test_consistency(sched, instruction_types={ShiftPhase})
         self.assertEqual(len(only_fc.instructions), 1)
-        self.assertEqual(len(no_fc.instructions), 6)
+        self.assertEqual(len(no_fc.instructions), 7)
 
         # test on SetFrequency
-        only_sf, no_sf = \
-            self._filter_and_test_consistency(sched,
-                                              instruction_types=[SetFrequency])
-        for _, inst in only_sf.instructions:
+        only_setf, no_setf = self._filter_and_test_consistency(
+            sched, instruction_types=[SetFrequency])
+        for _, inst in only_setf.instructions:
             self.assertTrue(isinstance(inst, SetFrequency))
-        self.assertEqual(len(only_sf.instructions), 1)
-        self.assertEqual(len(no_sf.instructions), 6)
+        self.assertEqual(len(only_setf.instructions), 1)
+        self.assertEqual(len(no_setf.instructions), 7)
+
+        # test on ShiftFrequency
+        only_shiftf, no_shiftf = \
+            self._filter_and_test_consistency(sched,
+                                              instruction_types=[ShiftFrequency])
+        for _, inst in only_shiftf.instructions:
+            self.assertTrue(isinstance(inst, ShiftFrequency))
+        self.assertEqual(len(only_shiftf.instructions), 1)
+        self.assertEqual(len(no_shiftf.instructions), 7)
 
     def test_filter_intervals(self):
         """Test filtering on intervals."""

test/python/qobj/test_pulse_converter.py

@@ -23,7 +23,7 @@ from qiskit.qobj.converters import (InstructionToQobjConverter, QobjToInstructio
                                     LoConfigConverter)
 from qiskit.pulse.commands import (SamplePulse, FrameChange, PersistentValue, Snapshot, Acquire,
                                    Gaussian, GaussianSquare, Constant, Drag)
-from qiskit.pulse.instructions import ShiftPhase, SetFrequency, Play, Delay
+from qiskit.pulse.instructions import ShiftPhase, SetFrequency, Play, Delay, ShiftFrequency
 from qiskit.pulse.channels import (DriveChannel, ControlChannel, MeasureChannel, AcquireChannel,
                                    MemorySlot, RegisterSlot)
 from qiskit.pulse.schedule import ParameterizedSchedule, Schedule
@@ -157,6 +157,20 @@ class TestInstructionToQobjConverter(QiskitTestCase):
 
         self.assertEqual(converter(0, instruction), valid_qobj)
 
+    def test_shift_frequency(self):
+        """Test converted qobj from ShiftFrequency."""
+        converter = InstructionToQobjConverter(PulseQobjInstruction, meas_level=2)
+        instruction = ShiftFrequency(8.0e9, DriveChannel(0))
+
+        valid_qobj = PulseQobjInstruction(
+            name='shiftf',
+            ch='d0',
+            t0=0,
+            frequency=8.0
+        )
+
+        self.assertEqual(converter(0, instruction), valid_qobj)
+
     def test_persistent_value(self):
         """Test converted qobj from PersistentValueInstruction."""
         converter = InstructionToQobjConverter(PulseQobjInstruction, meas_level=2)
@@ -301,7 +315,7 @@ class TestQobjToInstructionConverter(QiskitTestCase):
         self.assertEqual(converted_instruction.instructions[0][-1], instruction)
 
     def test_set_frequency(self):
-        """Test converted qobj from FrameChangeInstruction."""
+        """Test converted qobj from SetFrequency."""
         instruction = SetFrequency(8.0e9, DriveChannel(0))
 
         qobj = PulseQobjInstruction(name='setf', ch='d0', t0=0, frequency=8.0)
@@ -312,6 +326,18 @@ class TestQobjToInstructionConverter(QiskitTestCase):
         self.assertEqual(converted_instruction.instructions[0][-1], instruction)
         self.assertTrue('frequency' in qobj.to_dict())
 
+    def test_shift_frequency(self):
+        """Test converted qobj from ShiftFrequency."""
+        instruction = ShiftFrequency(8.0e9, DriveChannel(0))
+
+        qobj = PulseQobjInstruction(name='shiftf', ch='d0', t0=0, frequency=8.0)
+        converted_instruction = self.converter(qobj)
+
+        self.assertEqual(converted_instruction.start_time, 0)
+        self.assertEqual(converted_instruction.duration, 0)
+        self.assertEqual(converted_instruction.instructions[0][-1], instruction)
+        self.assertTrue('frequency' in qobj.to_dict())
+
     def test_delay(self):
         """Test converted qobj from Delay."""
         instruction = Delay(10, DriveChannel(0))

test/python/qobj/test_qobj.py

@@ -232,6 +232,7 @@ class TestPulseQobj(QiskitTestCase):
                     PulseQobjInstruction(name='pv', t0=10, ch='d0', val=0.1 + 0.0j),
                     PulseQobjInstruction(name='pv', t0=10, ch='d0', val='P1'),
                     PulseQobjInstruction(name='setf', t0=10, ch='d0', frequency=8.0),
+                    PulseQobjInstruction(name='shiftf', t0=10, ch='d0', frequency=4.0),
                     PulseQobjInstruction(name='acquire', t0=15, duration=5,
                                          qubits=[0], memory_slot=[0],
                                          kernels=[
@@ -266,6 +267,7 @@ class TestPulseQobj(QiskitTestCase):
                     {'name': 'pv', 't0': 10, 'ch': 'd0', 'val': 0.1+0j},
                     {'name': 'pv', 't0': 10, 'ch': 'd0', 'val': 'P1'},
                     {'name': 'setf', 't0': 10, 'ch': 'd0', 'frequency': 8.0},
+                    {'name': 'shiftf', 't0': 10, 'ch': 'd0', 'frequency': 4.0},
                     {'name': 'acquire', 't0': 15, 'duration': 5,
                      'qubits': [0], 'memory_slot': [0],
                      'kernels': [{'name': 'boxcar',

test/python/visualization/test_pulse_visualization_output.py

@@ -23,7 +23,7 @@ from qiskit.pulse import pulse_lib
 from qiskit.pulse.channels import (DriveChannel, MeasureChannel, ControlChannel, AcquireChannel,
                                    MemorySlot, RegisterSlot)
 from qiskit.pulse.commands import FrameChange
-from qiskit.pulse.instructions import SetFrequency, Play, Acquire, Delay, Snapshot
+from qiskit.pulse.instructions import SetFrequency, Play, Acquire, Delay, Snapshot, ShiftFrequency
 from qiskit.pulse.schedule import Schedule
 from qiskit.tools.visualization import HAS_MATPLOTLIB
 from qiskit.visualization import pulse_drawer
@@ -68,6 +68,7 @@ class TestPulseVisualizationImplementation(QiskitVisualizationTestCase):
             ControlChannel(0)))
         sched = sched.insert(60, FrameChange(phase=-1.57)(DriveChannel(0)))
         sched = sched.insert(60, SetFrequency(8.0, DriveChannel(0)))
+        sched = sched.insert(70, ShiftFrequency(4.0e6, DriveChannel(0)))
         sched = sched.insert(30, gp1(DriveChannel(1)))
         sched = sched.insert(60, gp0(ControlChannel(0)))
         sched = sched.insert(60, gs0(MeasureChannel(0)))