Prepare 0.7.6 release

.travis.yml

@@ -0,0 +1,29 @@
+---
+notifications:
+  email: false
+
+cache:
+  pip: true
+
+os: linux
+dist: bionic
+language: python
+python: 3.7
+jobs:
+  include:
+    - name: Build aarch64 wheels
+      arch: arm64
+      services:
+        - docker
+      install:
+        - echo ""
+      env:
+        - CIBW_BEFORE_ALL_LINUX="yum install -y https://dl.fedoraproject.org/pub/epel/7/aarch64/Packages/e/epel-release-7-12.noarch.rpm && yum install -y openblas-devel"
+        - CIBW_SKIP="cp27-* cp34-* cp35-* pp*"
+        - TWINE_USERNAME=qiskit
+        - CIBW_TEST_COMMAND="python {project}/tools/verify_wheels.py"
+      if: tag IS present
+      script:
+        - pip install -U twine importlib-metadata keyring cibuildwheel==1.9.0
+        - cibuildwheel --output-dir wheelhouse
+        - twine upload wheelhouse/*

docs/conf.py

@@ -46,7 +46,7 @@
 # The short X.Y version
 version = ''
 # The full version, including alpha/beta/rc tags
-release = '0.7.5'
+release = '0.7.6'
 
 # -- General configuration ---------------------------------------------------
 

qiskit/providers/aer/VERSION.txt

@@ -1 +1 @@
-0.7.5
+0.7.6

qiskit/providers/aer/backends/qasm_simulator.py

@@ -142,7 +142,7 @@ class QasmSimulator(AerBackend):
       to store a state vector. If a state vector needs more, an error
       is thrown. In general, a state vector of n-qubits uses 2^n complex
       values (16 Bytes). If set to 0, the maximum will be automatically
-      set to half the system memory size (Default: 0).
+      set to the system memory size (Default: 0).
 
     * ``optimize_ideal_threshold`` (int): Sets the qubit threshold for
       applying circuit optimization passes on ideal circuits.

qiskit/providers/aer/backends/statevector_simulator.py

@@ -81,7 +81,7 @@ class StatevectorSimulator(AerBackend):
       to store a state vector. If a state vector needs more, an error
       is thrown. In general, a state vector of n-qubits uses 2^n complex
       values (16 Bytes). If set to 0, the maximum will be automatically
-      set to half the system memory size (Default: 0).
+      set to the system memory size (Default: 0).
 
     * ``statevector_parallel_threshold`` (int): Sets the threshold that
       "n_qubits" must be greater than to enable OpenMP

qiskit/providers/aer/backends/unitary_simulator.py

@@ -87,7 +87,7 @@ class UnitarySimulator(AerBackend):
       to store a state vector. If a state vector needs more, an error
       is thrown. In general, a state vector of n-qubits uses 2^n complex
       values (16 Bytes). If set to 0, the maximum will be automatically
-      set to half the system memory size (Default: 0).
+      set to the system memory size (Default: 0).
 
     * ``"statevector_parallel_threshold"`` (int): Sets the threshold that
       2 * "n_qubits" must be greater than to enable OpenMP

qiskit/providers/aer/noise/noise_model.py

@@ -19,6 +19,11 @@
 
 from qiskit.circuit import Instruction
 from qiskit.providers import BaseBackend
+try:
+    from qiskit.providers import Backend as _Backend
+    BACKEND = (BaseBackend, _Backend)
+except ImportError:
+    BACKEND = BaseBackend
 from qiskit.providers.models import BackendProperties
 
 from ..backends.aerbackend import AerJSONEncoder
@@ -269,7 +274,7 @@ def from_backend(cls, backend,
         Raises:
             NoiseError: If the input backend is not valid.
         """
-        if isinstance(backend, BaseBackend):
+        if isinstance(backend, BACKEND):
             properties = backend.properties()
             basis_gates = backend.configuration().basis_gates
             if not properties:

qiskit/providers/aer/pulse/system_models/pulse_system_model.py

@@ -18,6 +18,11 @@
 from warnings import warn
 from collections import OrderedDict
 from qiskit.providers import BaseBackend
+try:
+    from qiskit.providers import Backend as _Backend
+    Backend = (BaseBackend, _Backend)
+except ImportError:
+    Backend = BaseBackend
 from ...aererror import AerError
 from .hamiltonian_model import HamiltonianModel
 
@@ -94,7 +99,7 @@ def from_backend(cls, backend, subsystem_list=None):
             AerError: If channel or u_channel_lo are invalid.
         """
 
-        if not isinstance(backend, BaseBackend):
+        if not isinstance(backend, Backend):
             raise AerError("{} is not a Qiskit backend".format(backend))
 
         # get relevant information from backend

releasenotes/notes/fix-conditional-noise-178f5d03b97a8dd5.yaml

@@ -0,0 +1,8 @@
+---
+fixes:
+  - |
+    Fixes a bug ([#1153](https://github.com/Qiskit/qiskit-aer/issues/1153))
+    where noise on conditional gates was always being applied regardless of
+    whether the conditional gate was actually applied based on the classical
+    register value. Now noise on a conditional gate will only be applied in
+    the case where the conditional gate is applied.

releasenotes/notes/issue1126-e2d51f660b0078db.yaml

@@ -0,0 +1,7 @@
+---
+
+fixes:
+  - |
+    Fixed issue #1126: bug in reporting measurement of a single qubit. The bug 
+    occured when copying the measured value to the output data structure.
+

src/controllers/controller.hpp

@@ -302,7 +302,7 @@ void Controller::clear_parallelization() {
   parallel_nested_ = false;
 
   explicit_parallelization_ = false;
-  max_memory_mb_ = get_system_memory_mb() / 2;
+  max_memory_mb_ = get_system_memory_mb();
 }
 
 void Controller::set_parallelization_experiments(

src/framework/linalg/vector.hpp

@@ -203,6 +203,7 @@ template <class T>
 Vector<T>::Vector(Vector<T> &&other) noexcept
     : size_(other.size_), data_(other.data_) {
   other.data_ = nullptr;
+  other.size_ = 0;
 }
 
 //-----------------------------------------------------------------------
@@ -214,6 +215,7 @@ template <class T> Vector<T> &Vector<T>::operator=(Vector<T> &&other) noexcept {
   size_ = other.size_;
   data_ = other.data_;
   other.data_ = nullptr;
+  other.size_ = 0;
   return *this;
 }
 

src/noise/noise_model.hpp

@@ -284,38 +284,57 @@ NoiseModel::param_gate_table_ = {
 
 NoiseModel::NoiseOps NoiseModel::sample_noise(const Operations::Op &op,
                                               RngEngine &rng) const {
+  // Noise operations
+  NoiseOps noise_ops;
   // Look to see if gate is a waltz gate for this error model
+  // NOTE this is deprecated and waltz gate noise sampling should be removed
   auto it = x90_gates_.find(op.name);
   if (it == x90_gates_.end()) {
     // Non-X90 based gate, run according to base model
-    return sample_noise_helper(op, rng);
+    noise_ops = sample_noise_helper(op, rng);
+  } else {
+    // Decompose ops in terms of their waltz implementation
+    auto gate = waltz_gate_table_.find(op.name);
+    if (gate != waltz_gate_table_.end()) {
+      switch (gate->second) {
+        case WaltzGate::u3:
+          noise_ops = sample_noise_x90_u3(op.qubits[0],
+                                          op.params[0], op.params[1], op.params[2],
+                                          rng);
+          break;
+        case WaltzGate::u2:
+          noise_ops = sample_noise_x90_u2(op.qubits[0],
+                                          op.params[0], op.params[1],
+                                           rng);
+          break;
+        case WaltzGate::x:
+          noise_ops =  sample_noise_x90_u3(op.qubits[0], M_PI, 0., M_PI, rng);
+          break;
+        case WaltzGate::y:
+          noise_ops = sample_noise_x90_u3(op.qubits[0],  M_PI, 0.5 * M_PI, 0.5 * M_PI, rng);
+          break;
+        case WaltzGate::h:
+          noise_ops = sample_noise_x90_u2(op.qubits[0], 0., M_PI, rng);
+          break;
+        default:
+          // The rest of the Waltz operations are noise free (u1 only)
+          noise_ops = {op};
+          break;
+      }
+    } else {
+      // something went wrong if we end up here
+      throw std::invalid_argument("Invalid waltz gate.");
+    }
   }
-  // Decompose ops in terms of their waltz implementation
-  auto gate = waltz_gate_table_.find(op.name);
-  if (gate != waltz_gate_table_.end()) {
-    switch (gate->second) {
-      case WaltzGate::u3:
-        return sample_noise_x90_u3(op.qubits[0],
-                                   op.params[0], op.params[1], op.params[2],
-                                   rng);
-      case WaltzGate::u2:
-        return sample_noise_x90_u2(op.qubits[0],
-                                   op.params[0], op.params[1],
-                                   rng);
-      case WaltzGate::x:
-        return sample_noise_x90_u3(op.qubits[0], M_PI, 0., M_PI, rng);
-      case WaltzGate::y:
-        return sample_noise_x90_u3(op.qubits[0],  M_PI, 0.5 * M_PI, 0.5 * M_PI, rng);
-      case WaltzGate::h:
-        return sample_noise_x90_u2(op.qubits[0], 0., M_PI, rng);
-      default:
-        // The rest of the Waltz operations are noise free (u1 only)
-        return {op};
+  // If original op is conditional, make all the noise operations also conditional
+  if (op.conditional) {
+    for (auto& noise_op : noise_ops) {
+      noise_op.conditional = op.conditional;
+      noise_op.conditional_reg = op.conditional_reg;
+      noise_op.bfunc = op.bfunc;
     }
-  } else {
-    // something went wrong if we end up here
-    throw std::invalid_argument("Invalid waltz gate.");
   }
+  return noise_ops;
 }
 
 

src/simulators/matrix_product_state/matrix_product_state.hpp

@@ -757,7 +757,6 @@ rvector_t State::measure_probs(const reg_t &qubits) const {
 std::vector<reg_t> State::sample_measure(const reg_t &qubits,
                                          uint_t shots,
                                          RngEngine &rng) {
-
   // There are two alternative algorithms for sample measure
   // We choose the one that is optimal relative to the total number 
   // of qubits,and the number of shots.
@@ -820,11 +819,11 @@ sample_measure_using_probabilities(const reg_t &qubits,
   std::vector<reg_t> all_samples;
   all_samples.reserve(shots);
   for (int_t val : allbit_samples) {
-    reg_t allbit_sample = Utils::int2reg(val, 2, qreg_.num_qubits());
+    reg_t allbit_sample = Utils::int2reg(val, 2, qubits.size());
     reg_t sample;
     sample.reserve(qubits.size());
-    for (uint_t qubit : qubits) {
-      sample.push_back(allbit_sample[qubit]);
+    for (uint_t j=0; j<qubits.size(); j++){
+      sample.push_back(allbit_sample[j]);
     }
     all_samples.push_back(sample);
   }

test/terra/reference/ref_measure.py

@@ -73,6 +73,20 @@ def measure_circuits_deterministic(allow_sampling=True):
         circuit.i(qr)
     circuits.append(circuit)
 
+    # Measure a single qubit (qubit 1) in |1> state
+    qr = QuantumRegister(3)
+    cr = ClassicalRegister(1)
+    circuit = QuantumCircuit(qr, cr)
+    circuit.h(0)
+    circuit.x(1)
+    circuit.cx(0, 2)
+    circuit.barrier(qr)
+    circuit.measure(1, 0)
+    if not allow_sampling:
+        circuit.barrier(qr)
+        circuit.i(qr)
+    circuits.append(circuit)
+
     return circuits
 
 
@@ -89,6 +103,8 @@ def measure_counts_deterministic(shots, hex_counts=True):
         targets.append({'0x2': shots})
         # Measure |11> state
         targets.append({'0x3': shots})
+        # Measure a single qubit (qubit 1) in |1> state
+        targets.append({'0x1': shots})
     else:
         # Measure |00> state
         targets.append({'00': shots})
@@ -98,6 +114,9 @@ def measure_counts_deterministic(shots, hex_counts=True):
         targets.append({'10': shots})
         # Measure |11> state
         targets.append({'11': shots})
+        # Measure a single qubit (qubit 1) in |1> state
+        targets.append({'0x1': shots})
+
     return targets
 
 

test/terra/reference/ref_pauli_noise.py

@@ -64,6 +64,20 @@ def pauli_gate_error_circuits():
     circuit.measure(qr, cr)
     circuits.append(circuit)
 
+    # 50% Pauli error on conditional gate that doesn't get applied
+    circuit = QuantumCircuit(qr, cr)
+    circuit.x(qr).c_if(cr, 1)
+    circuit.barrier(qr)
+    circuit.measure(qr, cr)
+    circuits.append(circuit)
+
+    # 50% Pauli error on conditional gate that does get applied
+    circuit = QuantumCircuit(qr, cr)
+    circuit.x(qr).c_if(cr, 0)
+    circuit.barrier(qr)
+    circuit.measure(qr, cr)
+    circuits.append(circuit)
+
     # 25% Pauli-X error on spectator for CX gate on [0, 1]
     qr = QuantumRegister(3, 'qr')
     cr = ClassicalRegister(3, 'cr')
@@ -106,6 +120,18 @@ def pauli_gate_error_noise_models():
     noise_model.add_quantum_error(error, 'id', [0])
     noise_models.append(noise_model)
 
+    # 50% Pauli error on conditional gate that doesn't get applied
+    error = pauli_error([('X', 0.5), ('I', 0.5)])
+    noise_model = NoiseModel()
+    noise_model.add_all_qubit_quantum_error(error, 'x')
+    noise_models.append(noise_model)
+
+    # 50% Pauli error on conditional gate that does get applied
+    error = pauli_error([('X', 0.5), ('I', 0.5)])
+    noise_model = NoiseModel()
+    noise_model.add_all_qubit_quantum_error(error, 'x')
+    noise_models.append(noise_model)
+
     # 25% Pauli-X error on spectator for CX gate on [0, 1]
     error = pauli_error([('XII', 0.25), ('III', 0.75)])
     noise_model = NoiseModel()
@@ -135,11 +161,18 @@ def pauli_gate_error_counts(shots, hex_counts=True):
     counts = [3 * shots / 4, shots / 4, 0, 0]
     counts_lists.append(counts)
 
+    # 50% Pauli error on conditional gate that doesn't get applied
+    counts = [shots, 0, 0, 0]
+    counts_lists.append(counts)
+
+    # 50% Pauli error on conditional gate that does get applied
+    counts = 4 * [shots / 4]
+    counts_lists.append(counts)
+
     # 25% Pauli-X error on spectator for CX gate on [0, 1]
     counts = [3 * shots / 4, 0, 0, 0, shots / 4, 0, 0, 0]
     counts_lists.append(counts)
 
-    # Convert to counts dict
     return [list2dict(i, hex_counts) for i in counts_lists]