Remove usage of qiskit.extensions

qiskit_aer/backends/aer_compiler.py

@@ -24,7 +24,7 @@
 from qiskit.circuit import QuantumCircuit, Clbit, ClassicalRegister, ParameterExpression
 from qiskit.circuit.classical.expr import Expr, Unary, Binary, Var, Value, ExprVisitor, iter_vars
 from qiskit.circuit.classical.types import Bool, Uint
-from qiskit.extensions import Initialize
+from qiskit.circuit.library import Initialize
 from qiskit.providers.options import Options
 from qiskit.pulse import Schedule, ScheduleBlock
 from qiskit.circuit.controlflow import (

qiskit_aer/backends/name_mapping.py

@@ -34,6 +34,8 @@
     CRZGate,
     MCU1Gate,
     MCXGrayCode,
+    Initialize,
+    UCGate,
 )
 from qiskit.circuit.controlflow import (
     IfElseOp,
@@ -43,8 +45,6 @@
     BreakLoopOp,
     SwitchCaseOp,
 )
-from qiskit.extensions import Initialize
-from qiskit.extensions.quantum_initializer import UCGate
 from qiskit.quantum_info.operators.channel.kraus import Kraus
 from qiskit.quantum_info.operators.channel import SuperOp
 from qiskit.quantum_info.operators.channel.quantum_channel import QuantumChannel

qiskit_aer/library/default_qubits.py

@@ -14,7 +14,6 @@
 """
 
 from qiskit.circuit import QuantumRegister
-from qiskit.extensions.exceptions import ExtensionError
 
 
 def default_qubits(circuit, qubits=None):
@@ -27,7 +26,7 @@ def default_qubits(circuit, qubits=None):
             [Default: None]
 
     Raises:
-            ExtensionError: if default qubits fails.
+        ValueError: if default qubits fails.
 
     Returns:
         list: qubits list.
@@ -37,9 +36,9 @@ def default_qubits(circuit, qubits=None):
     # This is needed for full register snapshots like statevector
     if isinstance(qubits, QuantumRegister):
         qubits = qubits[:]
-    if not qubits:
+    if qubits is None:
         qubits = list(circuit.qubits)
         if len(qubits) == 0:
-            raise ExtensionError("no qubits for snapshot")
+            raise ValueError("no qubits for snapshot")
 
     return qubits

qiskit_aer/library/save_instructions/save_amplitudes.py

@@ -14,7 +14,6 @@
 """
 
 from qiskit.circuit import QuantumCircuit
-from qiskit.extensions.exceptions import ExtensionError
 from .save_data import SaveSingleData, SaveAverageData
 from ..default_qubits import default_qubits
 
@@ -37,7 +36,7 @@ def __init__(self, num_qubits, params, label="amplitudes", pershot=False, condit
                                 [Default: False].
 
         Raises:
-            ExtensionError: if params is invalid for the specified number of qubits.
+            ValueError: if params is invalid for the specified number of qubits.
         """
         params = _format_amplitude_params(params, num_qubits)
         super().__init__(
@@ -78,7 +77,7 @@ def __init__(
                                 [Default: False].
 
         Raises:
-            ExtensionError: if params is invalid for the specified number of qubits.
+            ValueError: if params is invalid for the specified number of qubits.
         """
         params = _format_amplitude_params(params, num_qubits)
         super().__init__(
@@ -109,7 +108,7 @@ def save_amplitudes(self, params, label="amplitudes", pershot=False, conditional
         QuantumCircuit: with attached instruction.
 
     Raises:
-        ExtensionError: if params is invalid for the specified number of qubits.
+        ValueError: if params is invalid for the specified number of qubits.
     """
     qubits = default_qubits(self)
     instr = SaveAmplitudes(
@@ -139,7 +138,7 @@ def save_amplitudes_squared(
         QuantumCircuit: with attached instruction.
 
     Raises:
-        ExtensionError: if params is invalid for the specified number of qubits.
+        ValueError: if params is invalid for the specified number of qubits.
     """
     qubits = default_qubits(self)
     instr = SaveAmplitudesSquared(
@@ -161,7 +160,7 @@ def _format_amplitude_params(params, num_qubits=None):
         else:
             params = [int(i, 2) for i in params]
     if num_qubits and max(params) >= 2**num_qubits:
-        raise ExtensionError("Param values contain a state larger than the number of qubits")
+        raise ValueError("Param values contain a state larger than the number of qubits")
     return params
 
 

qiskit_aer/library/save_instructions/save_data.py

@@ -16,7 +16,6 @@
 import copy
 
 from qiskit.circuit import Instruction
-from qiskit.extensions.exceptions import ExtensionError
 
 
 class SaveData(Instruction):
@@ -39,19 +38,17 @@ def __init__(self, name, num_qubits, label, subtype="single", params=None):
                                    [Default: None].
 
         Raises:
-            ExtensionError: if the subtype string is invalid.
+            TypeError: if the subtype string is invalid.
 
         Additional Information:
             The supported subtypes are 'single', 'list', 'c_list', 'average',
             'c_average', 'accum', 'c_accum'.
         """
         if subtype not in self._allowed_subtypes:
-            raise ExtensionError("Invalid data subtype for SaveData instruction.")
+            raise TypeError("Invalid data subtype for SaveData instruction.")
 
         if not isinstance(label, str):
-            raise ExtensionError(
-                f"Invalid label for save data instruction, {label} must be a string."
-            )
+            raise TypeError(f"Invalid label for save data instruction, {label} must be a string.")
 
         if params is None:
             params = {}

qiskit_aer/library/save_instructions/save_expectation_value.py

@@ -16,7 +16,6 @@
 from numpy import allclose
 from qiskit.quantum_info import Pauli, SparsePauliOp, Operator
 from qiskit.circuit import QuantumCircuit
-from qiskit.extensions.exceptions import ExtensionError
 from .save_data import SaveAverageData
 
 
@@ -51,7 +50,8 @@ def __init__(
                                 values [Default: False].
 
         Raises:
-            ExtensionError: if the input operator is invalid or not Hermitian.
+            ValueError: if the input operator is not Hermitian.
+            TypeError: if the input operator is of invalid type.
 
         .. note::
 
@@ -64,7 +64,7 @@ def __init__(
         elif not isinstance(operator, SparsePauliOp):
             operator = SparsePauliOp.from_operator(Operator(operator))
         if not allclose(operator.coeffs.imag, 0):
-            raise ExtensionError("Input operator is not Hermitian.")
+            raise ValueError("Input operator is not Hermitian.")
         params = _expval_params(operator, variance=False)
         super().__init__(
             "save_expval",
@@ -109,7 +109,8 @@ def __init__(
                                 values [Default: False].
 
         Raises:
-            ExtensionError: if the input operator is invalid or not Hermitian.
+            ValueError: if the input operator is not Hermitian.
+            TypeError: if the input operator is of invalid type.
 
         .. note::
 
@@ -122,7 +123,7 @@ def __init__(
         elif not isinstance(operator, SparsePauliOp):
             operator = SparsePauliOp.from_operator(Operator(operator))
         if not allclose(operator.coeffs.imag, 0):
-            raise ExtensionError("Input operator is not Hermitian.")
+            raise ValueError("Input operator is not Hermitian.")
         params = _expval_params(operator, variance=True)
         super().__init__(
             "save_expval_var",
@@ -142,7 +143,7 @@ def _expval_params(operator, variance=False):
     elif not isinstance(operator, SparsePauliOp):
         operator = SparsePauliOp.from_operator(Operator(operator))
     if not isinstance(operator, SparsePauliOp):
-        raise ExtensionError("Invalid input operator")
+        raise TypeError("Invalid input operator")
 
     params = {}
 
@@ -196,7 +197,8 @@ def save_expectation_value(
         QuantumCircuit: with attached instruction.
 
     Raises:
-        ExtensionError: if the input operator is invalid or not Hermitian.
+        ValueError: if the input operator is not Hermitian.
+        TypeError: if the input operator is of invalid type.
 
     .. note::
 
@@ -237,7 +239,8 @@ def save_expectation_value_variance(
         QuantumCircuit: with attached instruction.
 
     Raises:
-        ExtensionError: if the input operator is invalid or not Hermitian.
+        ValueError: if the input operator is not Hermitian.
+        TypeError: if the input operator is of invalid type.
 
     .. note::
 

qiskit_aer/library/set_instructions/set_density_matrix.py

@@ -14,7 +14,6 @@
 """
 
 from qiskit.circuit import QuantumCircuit, Instruction
-from qiskit.extensions.exceptions import ExtensionError
 from qiskit.quantum_info import DensityMatrix
 from ..default_qubits import default_qubits
 
@@ -31,7 +30,7 @@ def __init__(self, state):
             state (DensityMatrix): a density matrix.
 
         Raises:
-            ExtensionError: if the input density matrix is not valid.
+            ValueError: if the input density matrix is not valid.
 
         .. note::
 
@@ -42,7 +41,7 @@ def __init__(self, state):
         if not isinstance(state, DensityMatrix):
             state = DensityMatrix(state)
         if not state.num_qubits or not state.is_valid():
-            raise ExtensionError("The input state is not valid")
+            raise ValueError("The input state is not valid")
         super().__init__("set_density_matrix", state.num_qubits, 0, [state.data])
 
 
@@ -56,8 +55,8 @@ def set_density_matrix(self, state):
         QuantumCircuit: with attached instruction.
 
     Raises:
-        ExtensionError: If the density matrix is the incorrect size for the
-                        current circuit.
+        ValueError: If the density matrix is the incorrect size for the
+            current circuit.
 
     .. note:
 
@@ -67,7 +66,7 @@ def set_density_matrix(self, state):
     if not isinstance(state, DensityMatrix):
         state = DensityMatrix(state)
     if not state.num_qubits or state.num_qubits != len(qubits):
-        raise ExtensionError(
+        raise ValueError(
             "The size of the density matrix for the set state"
             " instruction must be equal to the number of qubits"
             f" in the circuit (state.num_qubits ({state.num_qubits})"

qiskit_aer/library/set_instructions/set_matrix_product_state.py

@@ -14,7 +14,6 @@
 """
 
 from qiskit.circuit import QuantumCircuit, Instruction
-from qiskit.extensions.exceptions import ExtensionError
 from ..default_qubits import default_qubits
 
 
@@ -52,29 +51,29 @@ def set_matrix_product_state(self, state):
         QuantumCircuit: with attached instruction.
 
     Raises:
-        ExtensionError: If the structure of the state is incorrect
+        ValueError: If the structure of the state is incorrect
 
     .. note:
 
         This instruction is always defined across all qubits in a circuit.
     """
     qubits = default_qubits(self)
     if not isinstance(state, tuple) or len(state) != 2:
-        raise ExtensionError(
+        raise ValueError(
             "The input matrix product state is not valid.  Should be a list of 2 elements"
         )
     if not isinstance(state[0], list) or not isinstance(state[1], list):
-        raise ExtensionError(
+        raise ValueError(
             "The first element of the input matrix product state is not valid. Should be a list."
         )
     if len(state[0]) != len(state[1]) + 1:
-        raise ExtensionError(
+        raise ValueError(
             "The input matrix product state is not valid. "
             "Length of q_reg vector should be 1 more than length of lambda_reg"
         )
     for elem in state[0]:
         if not isinstance(elem, tuple) or len(elem) != 2:
-            raise ExtensionError(
+            raise ValueError(
                 "The input matrix product state is not valid."
                 "The first element should be a list of length 2"
             )

qiskit_aer/library/set_instructions/set_stabilizer.py

@@ -14,7 +14,6 @@
 """
 
 from qiskit.circuit import QuantumCircuit, Instruction
-from qiskit.extensions.exceptions import ExtensionError
 from qiskit.quantum_info import StabilizerState, Clifford
 from ..default_qubits import default_qubits
 
@@ -53,8 +52,8 @@ def set_stabilizer(self, state):
         QuantumCircuit: with attached instruction.
 
     Raises:
-        ExtensionError: If the state is the incorrect size for the
-                        current circuit.
+        ValueError: If the state is the incorrect size for the
+            current circuit.
 
     .. note:
 
@@ -66,7 +65,7 @@ def set_stabilizer(self, state):
     if not isinstance(state, Clifford):
         state = Clifford(state)
     if state.num_qubits != len(qubits):
-        raise ExtensionError(
+        raise ValueError(
             "The size of the Clifford for the set_stabilizer"
             " instruction must be equal to the number of qubits"
             f" in the circuit (state.num_qubits ({state.num_qubits})"

qiskit_aer/library/set_instructions/set_statevector.py

@@ -14,7 +14,6 @@
 """
 
 from qiskit.circuit import QuantumCircuit, Instruction
-from qiskit.extensions.exceptions import ExtensionError
 from qiskit.quantum_info import Statevector
 from ..default_qubits import default_qubits
 
@@ -31,7 +30,7 @@ def __init__(self, state):
             state (Statevector): a statevector.
 
         Raises:
-            ExtensionError: if the input is not a valid state.
+            ValueError: if the input is not a valid state.
 
         .. note::
 
@@ -42,7 +41,7 @@ def __init__(self, state):
         if not isinstance(state, Statevector):
             state = Statevector(state)
         if not state.num_qubits or not state.is_valid():
-            raise ExtensionError("The input statevector is not valid")
+            raise ValueError("The input statevector is not valid")
         super().__init__("set_statevector", state.num_qubits, 0, [state.data])
 
 
@@ -56,8 +55,8 @@ def set_statevector(self, state):
         QuantumCircuit: with attached instruction.
 
     Raises:
-        ExtensionError: If the state is the incorrect size for the
-                        current circuit.
+        ValueError: If the state is the incorrect size for the
+            current circuit.
 
     .. note:
 
@@ -67,7 +66,7 @@ def set_statevector(self, state):
     if not isinstance(state, Statevector):
         state = Statevector(state)
     if not state.num_qubits or state.num_qubits != len(qubits):
-        raise ExtensionError(
+        raise ValueError(
             "The size of the statevector for the set_statevector"
             " instruction must be equal to the number of qubits"
             f" in the circuit (state.num_qubits ({state.num_qubits})"