Making sure all pulse durations are positive in DDS to controls conversion (#68)

* Improving checks to make sure that the outputted controls contain only pulses with positive durations

* Writing more helpful error messages

Author: leoadec

qctrlopencontrols/dynamic_decoupling_sequences/driven_controls.py

@@ -77,21 +77,20 @@ def _check_maximum_rotation_rate(
     """
 
     # check against global parameters
-    if maximum_rabi_rate < 0. or maximum_rabi_rate > UPPER_BOUND_RABI_RATE:
+    if maximum_rabi_rate <= 0. or maximum_rabi_rate > UPPER_BOUND_RABI_RATE:
         raise ArgumentsValueError(
-            'Maximum rabi rate must be between 0. and maximum value of {0}'.format(
+            'Maximum rabi rate must be greater than 0 and less or equal to {0}'.format(
                 UPPER_BOUND_RABI_RATE),
             {'maximum_rabi_rate': maximum_rabi_rate},
             extras={'maximum_detuning_rate': maximum_detuning_rate,
                     'allowed_maximum_rabi_rate': UPPER_BOUND_RABI_RATE})
 
-    if maximum_detuning_rate < 0. or maximum_detuning_rate > UPPER_BOUND_DETUNING_RATE:
+    if maximum_detuning_rate <= 0. or maximum_detuning_rate > UPPER_BOUND_DETUNING_RATE:
         raise ArgumentsValueError(
-            'Maximum detuning rate must be between 0. and maximum value of {0}'.format(
+            'Maximum detuning rate must be greater than 0 and less or equal to {0}'.format(
                 UPPER_BOUND_DETUNING_RATE),
             {'maximum_detuning_rate': maximum_detuning_rate, },
             extras={'maximum_rabi_rate': maximum_rabi_rate,
-                    'allowed_maximum_rabi_rate': UPPER_BOUND_RABI_RATE,
                     'allowed_maximum_detuning_rate': UPPER_BOUND_DETUNING_RATE})
 
 
@@ -112,9 +111,11 @@ def convert_dds_to_driven_control(
     dynamic_decoupling_sequence : qctrlopencontrols.DynamicDecouplingSequence
         The base DDS
     maximum_rabi_rate : float, optional
-        Maximum Rabi Rate; Defaults to 2*pi
+        Maximum Rabi Rate; Defaults to 2*pi.
+        Must be greater than 0 and less or equal to UPPER_BOUND_RABI_RATE, if set.
     maximum_detuning_rate : float, optional
-        Maximum Detuning Rate; Defaults to 2*pi
+        Maximum Detuning Rate; Defaults to 2*pi.
+        Must be greater than 0 and less or equal to UPPER_BOUND_DETUNING_RATE, if set.
     minimum_segment_duration : float, optional
         If set, further restricts the duration of every segment of the Driven Controls.
         Defaults to 0, in which case it does not affect the duration of the pulses.
@@ -172,6 +173,12 @@ def convert_dds_to_driven_control(
     azimuthal_angles = dynamic_decoupling_sequence.azimuthal_angles
     detuning_rotations = dynamic_decoupling_sequence.detuning_rotations
 
+    # check if all Rabi rotations are valid (i.e. have positive values)
+    if np.any(np.less(rabi_rotations, 0.)):
+        raise ArgumentsValueError(
+            'Sequence contains negative values for Rabi rotations.',
+            {'dynamic_decoupling_sequence': str(dynamic_decoupling_sequence)})
+
     # check for valid operation
     if not _check_valid_operation(rabi_rotations=rabi_rotations,
                                   detuning_rotations=detuning_rotations):
@@ -182,15 +189,6 @@ def convert_dds_to_driven_control(
             extras={'maximum_rabi_rate': maximum_rabi_rate,
                     'maximum_detuning_rate': maximum_detuning_rate})
 
-    # check if detuning rate is supplied if there is a detuning_rotation > 0
-    if np.any(detuning_rotations > 0.) and maximum_detuning_rate is None:
-        raise ArgumentsValueError(
-            'Sequence operation includes detuning rotations. Please supply a valid '
-            'maximum_detuning_rate.',
-            {'detuning_rotations': dynamic_decoupling_sequence.detuning_rotations,
-             'maximum_detuning_rate': maximum_detuning_rate},
-            extras={'maximum_rabi_rate': maximum_rabi_rate})
-
     if offsets.size == 0:
         offsets = np.array([0, sequence_duration])
         rabi_rotations = np.array([0, 0])
@@ -239,29 +237,19 @@ def convert_dds_to_driven_control(
     # check if any of the pulses have gone outside the time limit [0, sequence_duration]
     # if yes, adjust the segment timing
     if pulse_start_ends[0, 0] < 0.:
-
-        if np.sum(np.abs(pulse_start_ends[0, :])) == 0:
-            pulse_start_ends[0, 0] = 0
-        else:
-            translation = 0. - (pulse_start_ends[0, 0])
-            pulse_start_ends[0, :] = pulse_start_ends[0, :] + translation
+        translation = 0. - (pulse_start_ends[0, 0])
+        pulse_start_ends[0, :] = pulse_start_ends[0, :] + translation
 
     if pulse_start_ends[-1, 1] > sequence_duration:
+        translation = pulse_start_ends[-1, 1] - sequence_duration
+        pulse_start_ends[-1, :] = pulse_start_ends[-1, :] - translation
 
-        if np.sum(np.abs(pulse_start_ends[0, :])) == 2 * sequence_duration:
-            pulse_start_ends[-1, 1] = sequence_duration
-        else:
-            translation = pulse_start_ends[-1, 1] - sequence_duration
-            pulse_start_ends[-1, :] = pulse_start_ends[-1, :] - translation
-
-    # four conditions to check
+    # three conditions to check
     # 1. Control segment start times should be monotonically increasing
     # 2. Control segment end times should be monotonically increasing
-    # 3. Control segment start time must be less than its end time
-    # 4. Adjacent segments should not be overlapping
+    # 3. Adjacent segments should not be overlapping
     if (np.any(pulse_start_ends[0:-1, 0] - pulse_start_ends[1:, 0] > 0.) or
             np.any(pulse_start_ends[0:-1, 1] - pulse_start_ends[1:, 1] > 0.) or
-            np.any(pulse_start_ends[:, 0] - pulse_start_ends[:, 1] > 0.) or
             np.any(pulse_start_ends[1:, 0]-pulse_start_ends[0:-1, 1] < 0.)):
 
         raise ArgumentsValueError('Pulse timing could not be properly deduced from '
@@ -284,7 +272,8 @@ def convert_dds_to_driven_control(
                                    'maximum_detuning_rate': maximum_detuning_rate,
                                    'minimum_segment_duration': minimum_segment_duration},
                                   extras={'deduced_pulse_start_timing': pulse_start_ends[:, 0],
-                                          'deduced_pulse_end_timing': pulse_start_ends[:, 1]})
+                                          'deduced_pulse_end_timing': pulse_start_ends[:, 1],
+                                          'gap_durations': gap_durations})
 
 
     if np.allclose(pulse_start_ends, 0.0):