removed unnecessary exception definitions and check_package method; simply moved the imports of the libraries inside the relevant methods

Author: Rajib Chakravorty

qctrlopencontrols/base/check_packages.py

@@ -20,14 +20,12 @@
 
 import numpy as np
 
-import cirq
-
 from ..dynamic_decoupling_sequences.dynamic_decoupling_sequence import DynamicDecouplingSequence
 from ..exceptions.exceptions import ArgumentsValueError
 from ..globals import (FIX_DURATION_UNITARY, INSTANT_UNITARY)
 
 
-def convert_dds_to_cirq_circuit(
+def convert_dds_to_cirq_circuit(    #pylint: disable=too-many-locals
         dynamic_decoupling_sequence,
         target_qubits=None,
         gate_time=0.1,
@@ -93,6 +91,8 @@ def convert_dds_to_cirq_circuit(
     any offset.
     """
 
+    import cirq
+
     if dynamic_decoupling_sequence is None:
         raise ArgumentsValueError('No dynamic decoupling sequence provided.',
                                   {'dynamic_decoupling_sequence': dynamic_decoupling_sequence})

qctrlopencontrols/cirq/circuit.py

@@ -20,13 +20,11 @@
 
 import numpy as np
 
-import cirq
-
 from ..dynamic_decoupling_sequences.dynamic_decoupling_sequence import DynamicDecouplingSequence
 from ..exceptions.exceptions import ArgumentsValueError
 
 
-def convert_dds_to_cirq_schedule(
+def convert_dds_to_cirq_schedule(   #pylint: disable=too-many-locals
         dynamic_decoupling_sequence,
         target_qubits=None,
         gate_time=0.1,
@@ -87,6 +85,8 @@ def convert_dds_to_cirq_schedule(
     any offset.
     """
 
+    import cirq
+
     if dynamic_decoupling_sequence is None:
         raise ArgumentsValueError('No dynamic decoupling sequence provided.',
                                   {'dynamic_decoupling_sequence': dynamic_decoupling_sequence})
@@ -146,8 +146,8 @@ def convert_dds_to_cirq_schedule(
         nonzero_pulse_counts = 3 - np.sum(zero_pulses)
         if nonzero_pulse_counts > 1:
             raise ArgumentsValueError(
-                'Open Controls support a sequence with one '
-                'valid pulse at any offset. Found sequence '
+                'Open Controls support a sequence with one'
+                'valid pulse at any offset. Found sequence'
                 'with multiple rotation operations at an offset.',
                 {'dynamic_decoupling_sequence': str(dynamic_decoupling_sequence),
                  'offset': dynamic_decoupling_sequence.offsets[op_idx],

qctrlopencontrols/cirq/schedule.py

@@ -57,79 +57,3 @@ def __init__(self, description, arguments, extras=None):
             for key in self.extras:
                 self.message += '\n' + str(key) + '=' + repr(self.extras[key])
         super(ArgumentsValueError, self).__init__(self.message)
-
-
-class PackageVersionMismatchError(QctrlError):
-    """Exception raised when the version of required third party packages found but is
-    below the minimum required.
-
-    Parameters
-    ----------
-    description : string
-        Description of the why the error is raised.
-    arguments : dict
-        Dictionary that contains the package name, required minimum version.
-    extras : dict, optional
-        Other variables, such as the version found in the system,
-        that may be relevant to the error. Defaults to None.
-    """
-
-    def __init__(self, description, arguments, extras=None):
-        self.description = description
-        self.arguments = arguments
-        self.extras = extras
-        self.message = self.description
-
-        for key in self.arguments:
-            self.message += '\n' + str(key) + '=' + repr(self.arguments[key])
-        if extras is not None:
-            for key in self.extras:
-                self.message += '\n' + str(key) + '=' + repr(self.extras[key])
-        super(PackageVersionMismatchError, self).__init__(self.message)
-
-
-class PackageNotFoundError(QctrlError):
-    """Exception raised when the required third party packages is not found.
-
-    Parameters
-    ----------
-    description : string
-        Description of the why the error is raised.
-    arguments : dict
-        Dictionary that contains the package name and the required minimum version.
-    extras : dict, optional
-        Other variables that may be relevant to the error. Defaults to None.
-    """
-
-    def __init__(self, description, arguments, extras=None):
-        self.description = description
-        self.arguments = arguments
-        self.extras = extras
-        self.message = self.description
-
-        for key in self.arguments:
-            self.message += '\n' + str(key) + '=' + repr(self.arguments[key])
-        if extras is not None:
-            for key in self.extras:
-                self.message += '\n' + str(key) + '=' + repr(self.extras[key])
-        super(PackageNotFoundError, self).__init__(self.message)
-
-
-class PackageImportError(QctrlError):
-    """Exception raised when a package cannot be imported.
-
-    Parameters
-    ----------
-    description : string
-        Description of the why the error is raised.
-    package_name : string, optional
-        The name of the package that could not be imported. Defaults to None.
-    """
-    def __init__(self, description, package_name=None):
-        self.description = description
-        self.package_name = package_name
-        self.message = self.description
-
-        if package_name:
-            self.message += '\n' + 'package' + '=' + repr(self.package_name)
-        super(PackageImportError, self).__init__(self.message)

qctrlopencontrols/exceptions/exceptions.py

@@ -20,17 +20,13 @@
 
 import numpy as np
 
-from pyquil import Program
-from pyquil.gates import I, RX, RY, RZ, MEASURE
-from pyquil.quil import Pragma
-
 from ..dynamic_decoupling_sequences.dynamic_decoupling_sequence import DynamicDecouplingSequence
 from ..exceptions.exceptions import ArgumentsValueError
 from ..globals import (
     FIX_DURATION_UNITARY, INSTANT_UNITARY)
 
 
-def convert_dds_to_pyquil_program(
+def convert_dds_to_pyquil_program(  #pylint: disable=too-many-locals
         dynamic_decoupling_sequence,
         target_qubits=None,
         gate_time=0.1,
@@ -93,6 +89,10 @@ def convert_dds_to_pyquil_program(
     any offset.
     """
 
+    from pyquil import Program
+    from pyquil.gates import I, RX, RY, RZ, MEASURE
+    from pyquil.quil import Pragma
+
     if dynamic_decoupling_sequence is None:
         raise ArgumentsValueError('No dynamic decoupling sequence provided.',
                                   {'dynamic_decoupling_sequence': dynamic_decoupling_sequence})

qctrlopencontrols/pyquil/program.py

@@ -11,12 +11,3 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-
-"""
-==============
-qiskit module
-==============
-"""
-
-# Minimum Qiskit version required
-QISKIT_TERRA_MINIMUM_VERSION = '0.8.2'

qctrlopencontrols/qiskit/__init__.py

@@ -21,10 +21,8 @@
 import numpy as np
 
 from ..globals import (FIX_DURATION_UNITARY, INSTANT_UNITARY)
-from ..qiskit import QISKIT_TERRA_MINIMUM_VERSION
 from ..dynamic_decoupling_sequences.dynamic_decoupling_sequence import DynamicDecouplingSequence
-from ..exceptions.exceptions import ArgumentsValueError, PackageImportError
-from ..base.check_packages import check_package
+from ..exceptions.exceptions import ArgumentsValueError
 
 
 def convert_dds_to_qiskit_quantum_circuit(
@@ -73,12 +71,6 @@ def convert_dds_to_qiskit_quantum_circuit(
     ------
     ArgumentsValueError
         If any of the input parameters are invalid
-    PackageNotFoundError
-        If Qiskit is not found
-    PackageVersionMismatchError
-        If the required minimum version of Qiskit is not found
-    PackageImportError
-        If Qiskit cannot be imported
 
     Notes
     -----
@@ -101,16 +93,9 @@ def convert_dds_to_qiskit_quantum_circuit(
     any offset.
     """
 
-    check_package('qiskit-terra', QISKIT_TERRA_MINIMUM_VERSION)
-
-    try:
-        from qiskit import (
-            QuantumRegister, ClassicalRegister, QuantumCircuit)
-        from qiskit.qasm import pi
-    except ImportError:
-        raise PackageImportError(
-            'Error while trying to import qiskit-terra.'
-        )
+    from qiskit import (
+        QuantumRegister, ClassicalRegister, QuantumCircuit)
+    from qiskit.qasm import pi
 
     if dynamic_decoupling_sequence is None:
         raise ArgumentsValueError('No dynamic decoupling sequence provided.',