INSTRUCTION
stringlengths
1
8.43k
RESPONSE
stringlengths
75
104k
Calculate the purity of a quantum state.
def purity(state): """Calculate the purity of a quantum state. Args: state (ndarray): a quantum state Returns: float: purity. """ rho = np.array(state) if rho.ndim == 1: return 1.0 return np.real(np.trace(rho.dot(rho)))
Return the corresponding OPENQASM string.
def qasm(self, prec=15): """Return the corresponding OPENQASM string.""" string = "gate " + self.name if self.arguments is not None: string += "(" + self.arguments.qasm(prec) + ")" string += " " + self.bitlist.qasm(prec) + "\n" string += "{\n" + self.body.qasm(prec) + "}" return string
Run the pass on the DAG and write the discovered commutation relations into the property_set.
def run(self, dag): """ Run the pass on the DAG, and write the discovered commutation relations into the property_set. """ # Initiate the commutation set self.property_set['commutation_set'] = defaultdict(list) # Build a dictionary to keep track of the gates on each qubit for wire in dag.wires: wire_name = "{0}[{1}]".format(str(wire[0].name), str(wire[1])) self.property_set['commutation_set'][wire_name] = [] # Add edges to the dictionary for each qubit for node in dag.topological_op_nodes(): for (_, _, edge_data) in dag.edges(node): edge_name = edge_data['name'] self.property_set['commutation_set'][(node, edge_name)] = -1 for wire in dag.wires: wire_name = "{0}[{1}]".format(str(wire[0].name), str(wire[1])) for current_gate in dag.nodes_on_wire(wire): current_comm_set = self.property_set['commutation_set'][wire_name] if not current_comm_set: current_comm_set.append([current_gate]) if current_gate not in current_comm_set[-1]: prev_gate = current_comm_set[-1][-1] if _commute(current_gate, prev_gate): current_comm_set[-1].append(current_gate) else: current_comm_set.append([current_gate]) temp_len = len(current_comm_set) self.property_set['commutation_set'][(current_gate, wire_name)] = temp_len - 1
Creates a backend widget.
def backend_widget(backend): """Creates a backend widget. """ config = backend.configuration().to_dict() props = backend.properties().to_dict() name = widgets.HTML(value="<h4>{name}</h4>".format(name=backend.name()), layout=widgets.Layout()) n_qubits = config['n_qubits'] qubit_count = widgets.HTML(value="<h5><b>{qubits}</b></h5>".format(qubits=n_qubits), layout=widgets.Layout(justify_content='center')) cmap = widgets.Output(layout=widgets.Layout(min_width='250px', max_width='250px', max_height='250px', min_height='250px', justify_content='center', align_items='center', margin='0px 0px 0px 0px')) with cmap: _cmap_fig = plot_gate_map(backend, plot_directed=False, label_qubits=False) if _cmap_fig is not None: display(_cmap_fig) # Prevents plot from showing up twice. plt.close(_cmap_fig) pending = generate_jobs_pending_widget() is_oper = widgets.HTML(value="<h5></h5>", layout=widgets.Layout(justify_content='center')) least_busy = widgets.HTML(value="<h5></h5>", layout=widgets.Layout(justify_content='center')) t1_units = props['qubits'][0][0]['unit'] avg_t1 = round(sum([q[0]['value'] for q in props['qubits']])/n_qubits, 1) t1_widget = widgets.HTML(value="<h5>{t1} {units}</h5>".format(t1=avg_t1, units=t1_units), layout=widgets.Layout()) t2_units = props['qubits'][0][1]['unit'] avg_t2 = round(sum([q[1]['value'] for q in props['qubits']])/n_qubits, 1) t2_widget = widgets.HTML(value="<h5>{t2} {units}</h5>".format(t2=avg_t2, units=t2_units), layout=widgets.Layout()) out = widgets.VBox([name, cmap, qubit_count, pending, least_busy, is_oper, t1_widget, t2_widget], layout=widgets.Layout(display='inline-flex', flex_flow='column', align_items='center')) out._is_alive = True return out
Updates the monitor info Called from another thread.
def update_backend_info(self, interval=60): """Updates the monitor info Called from another thread. """ my_thread = threading.currentThread() current_interval = 0 started = False all_dead = False stati = [None]*len(self._backends) while getattr(my_thread, "do_run", True) and not all_dead: if current_interval == interval or started is False: for ind, back in enumerate(self._backends): _value = self.children[ind].children[2].value _head = _value.split('<b>')[0] try: _status = back.status() stati[ind] = _status except Exception: # pylint: disable=W0703 self.children[ind].children[2].value = _value.replace( _head, "<h5 style='color:#ff5c49'>") self.children[ind]._is_alive = False else: self.children[ind]._is_alive = True self.children[ind].children[2].value = _value.replace( _head, "<h5>") idx = list(range(len(self._backends))) pending = [s.pending_jobs for s in stati] _, least_idx = zip(*sorted(zip(pending, idx))) # Make sure least pending is operational for ind in least_idx: if stati[ind].operational: least_pending_idx = ind break for var in idx: if var == least_pending_idx: self.children[var].children[4].value = "<h5 style='color:#34bc6e'>True</h5>" else: self.children[var].children[4].value = "<h5 style='color:#dc267f'>False</h5>" self.children[var].children[3].children[1].value = pending[var] self.children[var].children[3].children[1].max = max( self.children[var].children[3].children[1].max, pending[var]+10) if stati[var].operational: self.children[var].children[5].value = "<h5 style='color:#34bc6e'>True</h5>" else: self.children[var].children[5].value = "<h5 style='color:#dc267f'>False</h5>" started = True current_interval = 0 time.sleep(1) all_dead = not any([wid._is_alive for wid in self.children]) current_interval += 1
Generates a jobs_pending progress bar widget.
def generate_jobs_pending_widget(): """Generates a jobs_pending progress bar widget. """ pbar = widgets.IntProgress( value=0, min=0, max=50, description='', orientation='horizontal', layout=widgets.Layout(max_width='180px')) pbar.style.bar_color = '#71cddd' pbar_current = widgets.Label( value=str(pbar.value), layout=widgets.Layout(min_width='auto')) pbar_max = widgets.Label( value=str(pbar.max), layout=widgets.Layout(min_width='auto')) def _on_max_change(change): pbar_max.value = str(change['new']) def _on_val_change(change): pbar_current.value = str(change['new']) pbar.observe(_on_max_change, names='max') pbar.observe(_on_val_change, names='value') jobs_widget = widgets.HBox([pbar_current, pbar, pbar_max], layout=widgets.Layout(max_width='250px', min_width='250px', justify_content='center')) return jobs_widget
Flips the cx nodes to match the directed coupling map. Args: dag ( DAGCircuit ): DAG to map. Returns: DAGCircuit: The rearranged dag for the coupling map
def run(self, dag): """ Flips the cx nodes to match the directed coupling map. Args: dag (DAGCircuit): DAG to map. Returns: DAGCircuit: The rearranged dag for the coupling map Raises: TranspilerError: If the circuit cannot be mapped just by flipping the cx nodes. """ new_dag = DAGCircuit() if self.layout is None: # LegacySwap renames the register in the DAG and does not match the property set self.layout = Layout.generate_trivial_layout(*dag.qregs.values()) for layer in dag.serial_layers(): subdag = layer['graph'] for cnot_node in subdag.named_nodes('cx', 'CX'): control = cnot_node.qargs[0] target = cnot_node.qargs[1] physical_q0 = self.layout[control] physical_q1 = self.layout[target] if self.coupling_map.distance(physical_q0, physical_q1) != 1: raise TranspilerError('The circuit requires a connection between physical ' 'qubits %s and %s' % (physical_q0, physical_q1)) if (physical_q0, physical_q1) not in self.coupling_map.get_edges(): # A flip needs to be done # Create the involved registers if control[0] not in subdag.qregs.values(): subdag.add_qreg(control[0]) if target[0] not in subdag.qregs.values(): subdag.add_qreg(target[0]) # Add H gates around subdag.apply_operation_back(HGate(), [target], []) subdag.apply_operation_back(HGate(), [control], []) subdag.apply_operation_front(HGate(), [target], []) subdag.apply_operation_front(HGate(), [control], []) # Flips the CX cnot_node.qargs[0], cnot_node.qargs[1] = target, control new_dag.extend_back(subdag) return new_dag
Run one pass of cx cancellation on the circuit
def run(self, dag): """ Run one pass of cx cancellation on the circuit Args: dag (DAGCircuit): the directed acyclic graph to run on. Returns: DAGCircuit: Transformed DAG. """ cx_runs = dag.collect_runs(["cx"]) for cx_run in cx_runs: # Partition the cx_run into chunks with equal gate arguments partition = [] chunk = [] for i in range(len(cx_run) - 1): chunk.append(cx_run[i]) qargs0 = cx_run[i].qargs qargs1 = cx_run[i + 1].qargs if qargs0 != qargs1: partition.append(chunk) chunk = [] chunk.append(cx_run[-1]) partition.append(chunk) # Simplify each chunk in the partition for chunk in partition: if len(chunk) % 2 == 0: for n in chunk: dag.remove_op_node(n) else: for n in chunk[1:]: dag.remove_op_node(n) return dag
Return a single backend matching the specified filtering.
def get_backend(self, name=None, **kwargs): """Return a single backend matching the specified filtering. Args: name (str): name of the backend. **kwargs (dict): dict used for filtering. Returns: BaseBackend: a backend matching the filtering. Raises: QiskitBackendNotFoundError: if no backend could be found or more than one backend matches. """ backends = self.backends(name, **kwargs) if len(backends) > 1: raise QiskitBackendNotFoundError('More than one backend matches the criteria') elif not backends: raise QiskitBackendNotFoundError('No backend matches the criteria') return backends[0]
Return the shape for bipartite matrix
def _bipartite_shape(self): """Return the shape for bipartite matrix""" return (self._input_dim, self._output_dim, self._input_dim, self._output_dim)
Return the conjugate of the QuantumChannel.
def conjugate(self): """Return the conjugate of the QuantumChannel.""" return Choi(np.conj(self._data), self.input_dims(), self.output_dims())
Return the transpose of the QuantumChannel.
def transpose(self): """Return the transpose of the QuantumChannel.""" # Make bipartite matrix d_in, d_out = self.dim data = np.reshape(self._data, (d_in, d_out, d_in, d_out)) # Swap input and output indicies on bipartite matrix data = np.transpose(data, (1, 0, 3, 2)) # Transpose channel has input and output dimensions swapped data = np.reshape(data, (d_in * d_out, d_in * d_out)) return Choi( data, input_dims=self.output_dims(), output_dims=self.input_dims())
Return the composition channel self∘other.
def compose(self, other, qargs=None, front=False): """Return the composition channel self∘other. Args: other (QuantumChannel): a quantum channel. qargs (list): a list of subsystem positions to compose other on. front (bool): If False compose in standard order other(self(input)) otherwise compose in reverse order self(other(input)) [default: False] Returns: Choi: The composition channel as a Choi object. Raises: QiskitError: if other cannot be converted to a channel or has incompatible dimensions. """ if qargs is not None: return Choi( SuperOp(self).compose(other, qargs=qargs, front=front)) # Convert to Choi matrix if not isinstance(other, Choi): other = Choi(other) # Check dimensions match up if front and self._input_dim != other._output_dim: raise QiskitError( 'input_dim of self must match output_dim of other') if not front and self._output_dim != other._input_dim: raise QiskitError( 'input_dim of other must match output_dim of self') if front: first = np.reshape(other._data, other._bipartite_shape) second = np.reshape(self._data, self._bipartite_shape) input_dim = other._input_dim input_dims = other.input_dims() output_dim = self._output_dim output_dims = self.output_dims() else: first = np.reshape(self._data, self._bipartite_shape) second = np.reshape(other._data, other._bipartite_shape) input_dim = self._input_dim input_dims = self.input_dims() output_dim = other._output_dim output_dims = other.output_dims() # Contract Choi matrices for composition data = np.reshape( np.einsum('iAjB,AkBl->ikjl', first, second), (input_dim * output_dim, input_dim * output_dim)) return Choi(data, input_dims, output_dims)
The matrix power of the channel.
def power(self, n): """The matrix power of the channel. Args: n (int): compute the matrix power of the superoperator matrix. Returns: Choi: the matrix power of the SuperOp converted to a Choi channel. Raises: QiskitError: if the input and output dimensions of the QuantumChannel are not equal, or the power is not an integer. """ if n > 0: return super().power(n) return Choi(SuperOp(self).power(n))
Evolve a quantum state by the QuantumChannel.
def _evolve(self, state, qargs=None): """Evolve a quantum state by the QuantumChannel. Args: state (QuantumState): The input statevector or density matrix. qargs (list): a list of QuantumState subsystem positions to apply the operator on. Returns: DensityMatrix: the output quantum state as a density matrix. Raises: QiskitError: if the operator dimension does not match the specified QuantumState subsystem dimensions. """ # If subsystem evolution we use the SuperOp representation if qargs is not None: return SuperOp(self)._evolve(state, qargs) # Otherwise we compute full evolution directly state = self._format_state(state, density_matrix=True) if state.shape[0] != self._input_dim: raise QiskitError( "QuantumChannel input dimension is not equal to state dimension." ) return np.einsum('AB,AiBj->ij', state, np.reshape(self._data, self._bipartite_shape))
Return the tensor product channel.
def _tensor_product(self, other, reverse=False): """Return the tensor product channel. Args: other (QuantumChannel): a quantum channel. reverse (bool): If False return self ⊗ other, if True return if True return (other ⊗ self) [Default: False Returns: Choi: the tensor product channel as a Choi object. Raises: QiskitError: if other is not a QuantumChannel subclass. """ # Convert other to Choi if not isinstance(other, Choi): other = Choi(other) if reverse: input_dims = self.input_dims() + other.input_dims() output_dims = self.output_dims() + other.output_dims() data = _bipartite_tensor( other.data, self._data, shape1=other._bipartite_shape, shape2=self._bipartite_shape) else: input_dims = other.input_dims() + self.input_dims() output_dims = other.output_dims() + self.output_dims() data = _bipartite_tensor( self._data, other.data, shape1=self._bipartite_shape, shape2=other._bipartite_shape) return Choi(data, input_dims, output_dims)
Get the number and size of unique registers from bit_labels list.
def _get_register_specs(bit_labels): """Get the number and size of unique registers from bit_labels list. Args: bit_labels (list): this list is of the form:: [['reg1', 0], ['reg1', 1], ['reg2', 0]] which indicates a register named "reg1" of size 2 and a register named "reg2" of size 1. This is the format of classic and quantum bit labels in qobj header. Yields: tuple: iterator of register_name:size pairs. """ it = itertools.groupby(bit_labels, operator.itemgetter(0)) for register_name, sub_it in it: yield register_name, max(ind[1] for ind in sub_it) + 1
Truncate long floats
def _truncate_float(matchobj, format_str='0.2g'): """Truncate long floats Args: matchobj (re.Match): contains original float format_str (str): format specifier Returns: str: returns truncated float """ if matchobj.group(0): return format(float(matchobj.group(0)), format_str) return ''
Return LaTeX string representation of circuit.
def latex(self, aliases=None): """Return LaTeX string representation of circuit. This method uses the LaTeX Qconfig package to create a graphical representation of the circuit. Returns: string: for writing to a LaTeX file. """ self._initialize_latex_array(aliases) self._build_latex_array(aliases) header_1 = r"""% \documentclass[preview]{standalone} % If the image is too large to fit on this documentclass use \documentclass[draft]{beamer} """ beamer_line = "\\usepackage[size=custom,height=%d,width=%d,scale=%.1f]{beamerposter}\n" header_2 = r"""% instead and customize the height and width (in cm) to fit. % Large images may run out of memory quickly. % To fix this use the LuaLaTeX compiler, which dynamically % allocates memory. \usepackage[braket, qm]{qcircuit} \usepackage{amsmath} \pdfmapfile{+sansmathaccent.map} % \usepackage[landscape]{geometry} % Comment out the above line if using the beamer documentclass. \begin{document} \begin{equation*}""" qcircuit_line = r""" \Qcircuit @C=%.1fem @R=%.1fem @!R { """ output = io.StringIO() output.write(header_1) output.write('%% img_width = %d, img_depth = %d\n' % (self.img_width, self.img_depth)) output.write(beamer_line % self._get_beamer_page()) output.write(header_2) output.write(qcircuit_line % (self.column_separation, self.row_separation)) for i in range(self.img_width): output.write("\t \t") for j in range(self.img_depth + 1): cell_str = self._latex[i][j] # Don't truncate offset float if drawing a barrier if 'barrier' in cell_str: output.write(cell_str) else: # floats can cause "Dimension too large" latex error in # xymatrix this truncates floats to avoid issue. cell_str = re.sub(r'[-+]?\d*\.\d{2,}|\d{2,}', _truncate_float, cell_str) output.write(cell_str) if j != self.img_depth: output.write(" & ") else: output.write(r'\\' + '\n') output.write('\t }\n') output.write('\\end{equation*}\n\n') output.write('\\end{document}') contents = output.getvalue() output.close() return contents
Get depth information for the circuit.
def _get_image_depth(self): """Get depth information for the circuit. Returns: int: number of columns in the circuit int: total size of columns in the circuit """ max_column_widths = [] for layer in self.ops: # store the max width for the layer current_max = 0 for op in layer: # update current op width arg_str_len = 0 # the wide gates for arg in op.op.params: arg_str = re.sub(r'[-+]?\d*\.\d{2,}|\d{2,}', _truncate_float, str(arg)) arg_str_len += len(arg_str) # the width of the column is the max of all the gates in the column current_max = max(arg_str_len, current_max) max_column_widths.append(current_max) # wires in the beginning and end columns = 2 # each layer is one column columns += len(self.ops) # every 3 characters is roughly one extra 'unit' of width in the cell # the gate name is 1 extra 'unit' # the qubit/cbit labels plus initial states is 2 more # the wires poking out at the ends is 2 more sum_column_widths = sum(1 + v / 3 for v in max_column_widths) # could be a fraction so ceil return columns, math.ceil(sum_column_widths) + 4
Get height width & scale attributes for the beamer page.
def _get_beamer_page(self): """Get height, width & scale attributes for the beamer page. Returns: tuple: (height, width, scale) desirable page attributes """ # PIL python package limits image size to around a quarter gigabyte # this means the beamer image should be limited to < 50000 # if you want to avoid a "warning" too, set it to < 25000 PIL_limit = 40000 # the beamer latex template limits each dimension to < 19 feet # (i.e. 575cm) beamer_limit = 550 # columns are roughly twice as big as rows aspect_ratio = self.sum_row_heights / self.sum_column_widths # choose a page margin so circuit is not cropped margin_factor = 1.5 height = min(self.sum_row_heights * margin_factor, beamer_limit) width = min(self.sum_column_widths * margin_factor, beamer_limit) # if too large, make it fit if height * width > PIL_limit: height = min(np.sqrt(PIL_limit * aspect_ratio), beamer_limit) width = min(np.sqrt(PIL_limit / aspect_ratio), beamer_limit) # if too small, give it a minimum size height = max(height, 10) width = max(width, 10) return (height, width, self.scale)
Returns an array of strings containing \\ LaTeX for this circuit.
def _build_latex_array(self, aliases=None): """Returns an array of strings containing \\LaTeX for this circuit. If aliases is not None, aliases contains a dict mapping the current qubits in the circuit to new qubit names. We will deduce the register names and sizes from aliases. """ columns = 1 # Rename qregs if necessary if aliases: qregdata = {} for q in aliases.values(): if q[0] not in qregdata: qregdata[q[0]] = q[1] + 1 elif qregdata[q[0]] < q[1] + 1: qregdata[q[0]] = q[1] + 1 else: qregdata = self.qregs for column, layer in enumerate(self.ops, 1): for op in layer: if op.condition: mask = self._get_mask(op.condition[0]) cl_reg = self.clbit_list[self._ffs(mask)] if_reg = cl_reg[0] pos_2 = self.img_regs[cl_reg] if_value = format(op.condition[1], 'b').zfill(self.cregs[if_reg])[::-1] if op.name not in ['measure', 'barrier', 'snapshot', 'load', 'save', 'noise']: nm = op.name qarglist = op.qargs if aliases is not None: qarglist = map(lambda x: aliases[x], qarglist) if len(qarglist) == 1: pos_1 = self.img_regs[(qarglist[0][0], qarglist[0][1])] if op.condition: mask = self._get_mask(op.condition[0]) cl_reg = self.clbit_list[self._ffs(mask)] if_reg = cl_reg[0] pos_2 = self.img_regs[cl_reg] if nm == "x": self._latex[pos_1][column] = "\\gate{X}" elif nm == "y": self._latex[pos_1][column] = "\\gate{Y}" elif nm == "z": self._latex[pos_1][column] = "\\gate{Z}" elif nm == "h": self._latex[pos_1][column] = "\\gate{H}" elif nm == "s": self._latex[pos_1][column] = "\\gate{S}" elif nm == "sdg": self._latex[pos_1][column] = "\\gate{S^\\dag}" elif nm == "t": self._latex[pos_1][column] = "\\gate{T}" elif nm == "tdg": self._latex[pos_1][column] = "\\gate{T^\\dag}" elif nm == "u0": self._latex[pos_1][column] = "\\gate{U_0(%s)}" % ( op.op.params[0]) elif nm == "u1": self._latex[pos_1][column] = "\\gate{U_1(%s)}" % ( op.op.params[0]) elif nm == "u2": self._latex[pos_1][column] = \ "\\gate{U_2\\left(%s,%s\\right)}" % ( op.op.params[0], op.op.params[1]) elif nm == "u3": self._latex[pos_1][column] = ("\\gate{U_3(%s,%s,%s)}" % ( op.op.params[0], op.op.params[1], op.op.params[2])) elif nm == "rx": self._latex[pos_1][column] = "\\gate{R_x(%s)}" % ( op.op.params[0]) elif nm == "ry": self._latex[pos_1][column] = "\\gate{R_y(%s)}" % ( op.op.params[0]) elif nm == "rz": self._latex[pos_1][column] = "\\gate{R_z(%s)}" % ( op.op.params[0]) else: self._latex[pos_1][columns] = "\\gate{%s}" % nm gap = pos_2 - pos_1 for i in range(self.cregs[if_reg]): if if_value[i] == '1': self._latex[pos_2 + i][column] = \ "\\control \\cw \\cwx[-" + str(gap) + "]" gap = 1 else: self._latex[pos_2 + i][column] = \ "\\controlo \\cw \\cwx[-" + str(gap) + "]" gap = 1 else: if nm == "x": self._latex[pos_1][column] = "\\gate{X}" elif nm == "y": self._latex[pos_1][column] = "\\gate{Y}" elif nm == "z": self._latex[pos_1][column] = "\\gate{Z}" elif nm == "h": self._latex[pos_1][column] = "\\gate{H}" elif nm == "s": self._latex[pos_1][column] = "\\gate{S}" elif nm == "sdg": self._latex[pos_1][column] = "\\gate{S^\\dag}" elif nm == "t": self._latex[pos_1][column] = "\\gate{T}" elif nm == "tdg": self._latex[pos_1][column] = "\\gate{T^\\dag}" elif nm == "u0": self._latex[pos_1][column] = "\\gate{U_0(%s)}" % ( op.op.params[0]) elif nm == "u1": self._latex[pos_1][column] = "\\gate{U_1(%s)}" % ( op.op.params[0]) elif nm == "u2": self._latex[pos_1][column] = \ "\\gate{U_2\\left(%s,%s\\right)}" % ( op.op.params[0], op.op.params[1]) elif nm == "u3": self._latex[pos_1][column] = ("\\gate{U_3(%s,%s,%s)}" % ( op.op.params[0], op.op.params[1], op.op.params[2])) elif nm == "rx": self._latex[pos_1][column] = "\\gate{R_x(%s)}" % ( op.op.params[0]) elif nm == "ry": self._latex[pos_1][column] = "\\gate{R_y(%s)}" % ( op.op.params[0]) elif nm == "rz": self._latex[pos_1][column] = "\\gate{R_z(%s)}" % ( op.op.params[0]) elif nm == "reset": self._latex[pos_1][column] = ( "\\push{\\rule{.6em}{0em}\\ket{0}\\" "rule{.2em}{0em}} \\qw") else: self._latex[pos_1][columns] = "\\gate{%s}" % nm elif len(qarglist) == 2: pos_1 = self.img_regs[(qarglist[0][0], qarglist[0][1])] pos_2 = self.img_regs[(qarglist[1][0], qarglist[1][1])] if op.condition: pos_3 = self.img_regs[(if_reg, 0)] temp = [pos_1, pos_2, pos_3] temp.sort(key=int) bottom = temp[1] gap = pos_3 - bottom for i in range(self.cregs[if_reg]): if if_value[i] == '1': self._latex[pos_3 + i][column] = \ "\\control \\cw \\cwx[-" + str(gap) + "]" gap = 1 else: self._latex[pos_3 + i][column] = \ "\\controlo \\cw \\cwx[-" + str(gap) + "]" gap = 1 if nm == "cx": self._latex[pos_1][column] = \ "\\ctrl{" + str(pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\targ" elif nm == "cz": self._latex[pos_1][column] = \ "\\ctrl{" + str(pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\control\\qw" elif nm == "cy": self._latex[pos_1][column] = \ "\\ctrl{" + str(pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\gate{Y}" elif nm == "ch": self._latex[pos_1][column] = \ "\\ctrl{" + str(pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\gate{H}" elif nm == "swap": self._latex[pos_1][column] = "\\qswap" self._latex[pos_2][column] = \ "\\qswap \\qwx[" + str(pos_1 - pos_2) + "]" elif nm == "crz": self._latex[pos_1][column] = \ "\\ctrl{" + str(pos_2 - pos_1) + "}" self._latex[pos_2][column] = \ "\\gate{R_z(%s)}" % (op.op.params[0]) elif nm == "cu1": self._latex[pos_1][column - 1] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column - 1] = "\\control\\qw" self._latex[min(pos_1, pos_2)][column] = \ "\\dstick{%s}\\qw" % (op.op.params[0]) self._latex[max(pos_1, pos_2)][column] = "\\qw" elif nm == "cu3": self._latex[pos_1][column] = \ "\\ctrl{" + str(pos_2 - pos_1) + "}" self._latex[pos_2][column] = \ "\\gate{U_3(%s,%s,%s)}" % (op.op.params[0], op.op.params[1], op.op.params[2]) else: temp = [pos_1, pos_2] temp.sort(key=int) if nm == "cx": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\targ" elif nm == "cz": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\control\\qw" elif nm == "cy": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\gate{Y}" elif nm == "ch": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\gate{H}" elif nm == "swap": self._latex[pos_1][column] = "\\qswap" self._latex[pos_2][column] = \ "\\qswap \\qwx[" + str(pos_1 - pos_2) + "]" elif nm == "crz": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = \ "\\gate{R_z(%s)}" % (op.op.params[0]) elif nm == "cu1": self._latex[pos_1][column - 1] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column - 1] = "\\control\\qw" self._latex[min(pos_1, pos_2)][column] = \ "\\dstick{%s}\\qw" % (op.op.params[0]) self._latex[max(pos_1, pos_2)][column] = "\\qw" elif nm == "cu3": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = ("\\gate{U_3(%s,%s,%s)}" % ( op.op.params[0], op.op.params[1], op.op.params[2])) else: start_pos = min([pos_1, pos_2]) stop_pos = max([pos_1, pos_2]) if stop_pos - start_pos >= 2: delta = stop_pos - start_pos self._latex[start_pos][columns] = ( "\\multigate{%s}{%s}" % (delta, nm)) for i_pos in range(start_pos + 1, stop_pos + 1): self._latex[i_pos][columns] = "\\ghost{%s}" % nm else: self._latex[start_pos][columns] = ( "\\multigate{1}{%s}" % nm) self._latex[stop_pos][columns] = "\\ghost{%s}" % nm elif len(qarglist) == 3: pos_1 = self.img_regs[(qarglist[0][0], qarglist[0][1])] pos_2 = self.img_regs[(qarglist[1][0], qarglist[1][1])] pos_3 = self.img_regs[(qarglist[2][0], qarglist[2][1])] if op.condition: pos_4 = self.img_regs[(if_reg, 0)] temp = [pos_1, pos_2, pos_3, pos_4] temp.sort(key=int) bottom = temp[2] prev_column = [x[column - 1] for x in self._latex] for item, prev_entry in enumerate(prev_column): if 'barrier' in prev_entry: span = re.search('barrier{(.*)}', prev_entry) if span and any(i in temp for i in range( item, int(span.group(1)))): self._latex[item][column - 1] = \ prev_entry.replace( '\\barrier{', '\\barrier[-0.65em]{') gap = pos_4 - bottom for i in range(self.cregs[if_reg]): if if_value[i] == '1': self._latex[pos_4 + i][column] = \ "\\control \\cw \\cwx[-" + str(gap) + "]" gap = 1 else: self._latex[pos_4 + i][column] = \ "\\controlo \\cw \\cwx[-" + str(gap) + "]" gap = 1 if nm == "ccx": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\ctrl{" + str( pos_3 - pos_2) + "}" self._latex[pos_3][column] = "\\targ" if nm == "cswap": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\qswap" self._latex[pos_3][column] = \ "\\qswap \\qwx[" + str(pos_2 - pos_3) + "]" else: temp = [pos_1, pos_2, pos_3] temp.sort(key=int) prev_column = [x[column - 1] for x in self._latex] for item, prev_entry in enumerate(prev_column): if 'barrier' in prev_entry: span = re.search('barrier{(.*)}', prev_entry) if span and any(i in temp for i in range( item, int(span.group(1)))): self._latex[item][column - 1] = \ prev_entry.replace( '\\barrier{', '\\barrier[-0.65em]{') if nm == "ccx": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\ctrl{" + str( pos_3 - pos_2) + "}" self._latex[pos_3][column] = "\\targ" elif nm == "cswap": self._latex[pos_1][column] = "\\ctrl{" + str( pos_2 - pos_1) + "}" self._latex[pos_2][column] = "\\qswap" self._latex[pos_3][column] = \ "\\qswap \\qwx[" + str(pos_2 - pos_3) + "]" else: start_pos = min([pos_1, pos_2, pos_3]) stop_pos = max([pos_1, pos_2, pos_3]) if stop_pos - start_pos >= 3: delta = stop_pos - start_pos self._latex[start_pos][columns] = ( "\\multigate{%s}{%s}" % (delta, nm)) for i_pos in range(start_pos + 1, stop_pos + 1): self._latex[i_pos][columns] = "\\ghost{%s}" % nm else: self._latex[pos_1][columns] = ( "\\multigate{2}{%s}" % nm) self._latex[pos_2][columns] = "\\ghost{%s}" % nm self._latex[pos_3][columns] = "\\ghost{%s}" % nm elif len(qarglist) > 3: nbits = len(qarglist) pos_array = [self.img_regs[(qarglist[0][0], qarglist[0][1])]] for i in range(1, nbits): pos_array.append(self.img_regs[(qarglist[i][0], qarglist[i][1])]) pos_start = min(pos_array) pos_stop = max(pos_array) delta = pos_stop - pos_start self._latex[pos_start][columns] = ( "\\multigate{%s}{%s}" % (nbits - 1, nm)) for pos in range(pos_start + 1, pos_stop + 1): self._latex[pos][columns] = "\\ghost{%s}" % nm elif op.name == "measure": if (len(op.cargs) != 1 or len(op.qargs) != 1 or op.op.params): raise exceptions.VisualizationError("bad operation record") if op.condition: raise exceptions.VisualizationError( "If controlled measures currently not supported.") qname, qindex = op.qargs[0] cname, cindex = op.cargs[0] if aliases: newq = aliases[(qname, qindex)] qname = newq[0] qindex = newq[1] pos_1 = self.img_regs[(qname, qindex)] pos_2 = self.img_regs[(cname, cindex)] try: self._latex[pos_1][column] = "\\meter" prev_column = [x[column - 1] for x in self._latex] for item, prev_entry in enumerate(prev_column): if 'barrier' in prev_entry: span = re.search('barrier{(.*)}', prev_entry) if span and ( item + int(span.group(1))) - pos_1 >= 0: self._latex[item][column - 1] = \ prev_entry.replace( '\\barrier{', '\\barrier[-1.15em]{') self._latex[pos_2][column] = \ "\\cw \\cwx[-" + str(pos_2 - pos_1) + "]" except Exception as e: raise exceptions.VisualizationError( 'Error during Latex building: %s' % str(e)) elif op.name in ['barrier', 'snapshot', 'load', 'save', 'noise']: if self.plot_barriers: qarglist = op.qargs indexes = [self._get_qubit_index(x) for x in qarglist] start_bit = self.qubit_list[min(indexes)] if aliases is not None: qarglist = map(lambda x: aliases[x], qarglist) start = self.img_regs[start_bit] span = len(op.qargs) - 1 self._latex[start][column] = "\\qw \\barrier{" + str( span) + "}" else: raise exceptions.VisualizationError("bad node data")
Get the index number for a quantum bit Args: qubit ( tuple ): The tuple of the bit of the form ( register_name bit_number ) Returns: int: The index in the bit list Raises: VisualizationError: If the bit isn t found
def _get_qubit_index(self, qubit): """Get the index number for a quantum bit Args: qubit (tuple): The tuple of the bit of the form (register_name, bit_number) Returns: int: The index in the bit list Raises: VisualizationError: If the bit isn't found """ for i, bit in enumerate(self.qubit_list): if qubit == bit: qindex = i break else: raise exceptions.VisualizationError("unable to find bit for operation") return qindex
Loads the QObj schema for use in future validations.
def _load_schema(file_path, name=None): """Loads the QObj schema for use in future validations. Caches schema in _SCHEMAS module attribute. Args: file_path(str): Path to schema. name(str): Given name for schema. Defaults to file_path filename without schema. Return: schema(dict): Loaded schema. """ if name is None: # filename without extension name = os.path.splitext(os.path.basename(file_path))[0] if name not in _SCHEMAS: with open(file_path, 'r') as schema_file: _SCHEMAS[name] = json.load(schema_file) return _SCHEMAS[name]
Generate validator for JSON schema.
def _get_validator(name, schema=None, check_schema=True, validator_class=None, **validator_kwargs): """Generate validator for JSON schema. Args: name (str): Name for validator. Will be validator key in `_VALIDATORS` dict. schema (dict): JSON schema `dict`. If not provided searches for schema in `_SCHEMAS`. check_schema (bool): Verify schema is valid. validator_class (jsonschema.IValidator): jsonschema IValidator instance. Default behavior is to determine this from the schema `$schema` field. **validator_kwargs (dict): Additional keyword arguments for validator. Return: jsonschema.IValidator: Validator for JSON schema. Raises: SchemaValidationError: Raised if validation fails. """ if schema is None: try: schema = _SCHEMAS[name] except KeyError: raise SchemaValidationError("Valid schema name or schema must " "be provided.") if name not in _VALIDATORS: # Resolve JSON spec from schema if needed if validator_class is None: validator_class = jsonschema.validators.validator_for(schema) # Generate and store validator in _VALIDATORS _VALIDATORS[name] = validator_class(schema, **validator_kwargs) validator = _VALIDATORS[name] if check_schema: validator.check_schema(schema) return validator
Load all default schemas into _SCHEMAS.
def _load_schemas_and_validators(): """Load all default schemas into `_SCHEMAS`.""" schema_base_path = os.path.join(os.path.dirname(__file__), '../..') for name, path in _DEFAULT_SCHEMA_PATHS.items(): _load_schema(os.path.join(schema_base_path, path), name) _get_validator(name)
Validates JSON dict against a schema.
def validate_json_against_schema(json_dict, schema, err_msg=None): """Validates JSON dict against a schema. Args: json_dict (dict): JSON to be validated. schema (dict or str): JSON schema dictionary or the name of one of the standards schemas in Qiskit to validate against it. The list of standard schemas is: ``backend_configuration``, ``backend_properties``, ``backend_status``, ``default_pulse_configuration``, ``job_status``, ``qobj``, ``result``. err_msg (str): Optional error message. Raises: SchemaValidationError: Raised if validation fails. """ try: if isinstance(schema, str): schema_name = schema schema = _SCHEMAS[schema_name] validator = _get_validator(schema_name) validator.validate(json_dict) else: jsonschema.validate(json_dict, schema) except jsonschema.ValidationError as err: if err_msg is None: err_msg = "JSON failed validation. Set Qiskit log level to DEBUG " \ "for further information." newerr = SchemaValidationError(err_msg) newerr.__cause__ = _SummaryValidationError(err) logger.debug('%s', _format_causes(err)) raise newerr
Return a cascading explanation of the validation error.
def _format_causes(err, level=0): """Return a cascading explanation of the validation error. Returns a cascading explanation of the validation error in the form of:: <validator> failed @ <subfield_path> because of: <validator> failed @ <subfield_path> because of: ... <validator> failed @ <subfield_path> because of: ... ... For example:: 'oneOf' failed @ '<root>' because of: 'required' failed @ '<root>.config' because of: 'meas_level' is a required property Meaning the validator 'oneOf' failed while validating the whole object because of the validator 'required' failing while validating the property 'config' because its 'meas_level' field is missing. The cascade repeats the format "<validator> failed @ <path> because of" until there are no deeper causes. In this case, the string representation of the error is shown. Args: err (jsonschema.ValidationError): the instance to explain. level (int): starting level of indentation for the cascade of explanations. Return: str: a formatted string with the explanation of the error. """ lines = [] def _print(string, offset=0): lines.append(_pad(string, offset=offset)) def _pad(string, offset=0): padding = ' ' * (level + offset) padded_lines = [padding + line for line in string.split('\n')] return '\n'.join(padded_lines) def _format_path(path): def _format(item): if isinstance(item, str): return '.{}'.format(item) return '[{}]'.format(item) return ''.join(['<root>'] + list(map(_format, path))) _print('\'{}\' failed @ \'{}\' because of:'.format( err.validator, _format_path(err.absolute_path))) if not err.context: _print(str(err.message), offset=1) else: for suberr in err.context: lines.append(_format_causes(suberr, level+1)) return '\n'.join(lines)
Return the corresponding OPENQASM string.
def qasm(self, prec=15): """Return the corresponding OPENQASM string.""" return ",".join([self.children[j].qasm(prec) for j in range(self.size())])
Majority gate.
def majority(p, a, b, c): """Majority gate.""" p.cx(c, b) p.cx(c, a) p.ccx(a, b, c)
Unmajority gate.
def unmajority(p, a, b, c): """Unmajority gate.""" p.ccx(a, b, c) p.cx(c, a) p.cx(a, b)
Returns a dict of DAGNode: Barrier objects where the barrier needs to be inserted where the corresponding DAGNode appears in the main DAG
def _collect_potential_merges(dag, barriers): """ Returns a dict of DAGNode : Barrier objects, where the barrier needs to be inserted where the corresponding DAGNode appears in the main DAG """ # if only got 1 or 0 barriers then can't merge if len(barriers) < 2: return None # mapping from the node that will be the main barrier to the # barrier object that gets built up node_to_barrier_qubits = {} # Start from the first barrier current_barrier = barriers[0] end_of_barrier = current_barrier current_barrier_nodes = [current_barrier] current_qubits = set(current_barrier.qargs) current_ancestors = dag.ancestors(current_barrier) current_descendants = dag.descendants(current_barrier) barrier_to_add = Barrier(len(current_qubits)) for next_barrier in barriers[1:]: # Remove all barriers that have already been included in this new barrier from the set # of ancestors/descendants as they will be removed from the new DAG when it is created next_ancestors = {nd for nd in dag.ancestors(next_barrier) if nd not in current_barrier_nodes} next_descendants = {nd for nd in dag.descendants(next_barrier) if nd not in current_barrier_nodes} next_qubits = set(next_barrier.qargs) if ( not current_qubits.isdisjoint(next_qubits) and current_ancestors.isdisjoint(next_descendants) and current_descendants.isdisjoint(next_ancestors) ): # can be merged current_ancestors = current_ancestors | next_ancestors current_descendants = current_descendants | next_descendants current_qubits = current_qubits | next_qubits # update the barrier that will be added back to include this barrier barrier_to_add = Barrier(len(current_qubits)) else: # store the previously made barrier if barrier_to_add: node_to_barrier_qubits[end_of_barrier] = current_qubits # reset the properties current_qubits = set(next_barrier.qargs) current_ancestors = dag.ancestors(next_barrier) current_descendants = dag.descendants(next_barrier) barrier_to_add = Barrier(len(current_qubits)) current_barrier_nodes = [] end_of_barrier = next_barrier current_barrier_nodes.append(end_of_barrier) if barrier_to_add: node_to_barrier_qubits[end_of_barrier] = current_qubits return node_to_barrier_qubits
Draw a quantum circuit to different formats ( set by output parameter ): 0. text: ASCII art TextDrawing that can be printed in the console. 1. latex: high - quality images but heavy external software dependencies 2. matplotlib: purely in Python with no external dependencies
def circuit_drawer(circuit, scale=0.7, filename=None, style=None, output='text', interactive=False, line_length=None, plot_barriers=True, reverse_bits=False, justify=None): """Draw a quantum circuit to different formats (set by output parameter): 0. text: ASCII art TextDrawing that can be printed in the console. 1. latex: high-quality images, but heavy external software dependencies 2. matplotlib: purely in Python with no external dependencies Args: circuit (QuantumCircuit): the quantum circuit to draw scale (float): scale of image to draw (shrink if < 1) filename (str): file path to save image to style (dict or str): dictionary of style or file name of style file. This option is only used by the `mpl`, `latex`, and `latex_source` output types. If a str is passed in that is the path to a json file which contains that will be open, parsed, and then used just as the input dict. output (TextDrawing): Select the output method to use for drawing the circuit. Valid choices are `text`, `latex`, `latex_source`, `mpl`. Note if one is not specified it will use latex and if that fails fallback to mpl. However this behavior is deprecated and in a future release the default will change. interactive (bool): when set true show the circuit in a new window (for `mpl` this depends on the matplotlib backend being used supporting this). Note when used with either the `text` or the `latex_source` output type this has no effect and will be silently ignored. line_length (int): Sets the length of the lines generated by `text` output type. This useful when the drawing does not fit in the console. If None (default), it will try to guess the console width using shutil.get_terminal_size(). However, if you're running in jupyter the default line length is set to 80 characters. If you don't want pagination at all, set `line_length=-1`. reverse_bits (bool): When set to True reverse the bit order inside registers for the output visualization. plot_barriers (bool): Enable/disable drawing barriers in the output circuit. Defaults to True. justify (string): Options are `left`, `right` or `none`, if anything else is supplied it defaults to left justified. It refers to where gates should be placed in the output circuit if there is an option. `none` results in each gate being placed in its own column. Currently only supported by text drawer. Returns: PIL.Image: (output `latex`) an in-memory representation of the image of the circuit diagram. matplotlib.figure: (output `mpl`) a matplotlib figure object for the circuit diagram. String: (output `latex_source`). The LaTeX source code. TextDrawing: (output `text`). A drawing that can be printed as ascii art Raises: VisualizationError: when an invalid output method is selected ImportError: when the output methods requieres non-installed libraries. .. _style-dict-doc: The style dict kwarg contains numerous options that define the style of the output circuit visualization. While the style dict is used by the `mpl`, `latex`, and `latex_source` outputs some options in that are only used by the `mpl` output. These options are defined below, if it is only used by the `mpl` output it is marked as such: textcolor (str): The color code to use for text. Defaults to `'#000000'` (`mpl` only) subtextcolor (str): The color code to use for subtext. Defaults to `'#000000'` (`mpl` only) linecolor (str): The color code to use for lines. Defaults to `'#000000'` (`mpl` only) creglinecolor (str): The color code to use for classical register lines `'#778899'`(`mpl` only) gatetextcolor (str): The color code to use for gate text `'#000000'` (`mpl` only) gatefacecolor (str): The color code to use for gates. Defaults to `'#ffffff'` (`mpl` only) barrierfacecolor (str): The color code to use for barriers. Defaults to `'#bdbdbd'` (`mpl` only) backgroundcolor (str): The color code to use for the background. Defaults to `'#ffffff'` (`mpl` only) fontsize (int): The font size to use for text. Defaults to 13 (`mpl` only) subfontsize (int): The font size to use for subtext. Defaults to 8 (`mpl` only) displaytext (dict): A dictionary of the text to use for each element type in the output visualization. The default values are: { 'id': 'id', 'u0': 'U_0', 'u1': 'U_1', 'u2': 'U_2', 'u3': 'U_3', 'x': 'X', 'y': 'Y', 'z': 'Z', 'h': 'H', 's': 'S', 'sdg': 'S^\\dagger', 't': 'T', 'tdg': 'T^\\dagger', 'rx': 'R_x', 'ry': 'R_y', 'rz': 'R_z', 'reset': '\\left|0\\right\\rangle' } You must specify all the necessary values if using this. There is no provision for passing an incomplete dict in. (`mpl` only) displaycolor (dict): The color codes to use for each circuit element. By default all values default to the value of `gatefacecolor` and the keys are the same as `displaytext`. Also, just like `displaytext` there is no provision for an incomplete dict passed in. (`mpl` only) latexdrawerstyle (bool): When set to True enable latex mode which will draw gates like the `latex` output modes. (`mpl` only) usepiformat (bool): When set to True use radians for output (`mpl` only) fold (int): The number of circuit elements to fold the circuit at. Defaults to 20 (`mpl` only) cregbundle (bool): If set True bundle classical registers (`mpl` only) showindex (bool): If set True draw an index. (`mpl` only) compress (bool): If set True draw a compressed circuit (`mpl` only) figwidth (int): The maximum width (in inches) for the output figure. (`mpl` only) dpi (int): The DPI to use for the output image. Defaults to 150 (`mpl` only) margin (list): `mpl` only creglinestyle (str): The style of line to use for classical registers. Choices are `'solid'`, `'doublet'`, or any valid matplotlib `linestyle` kwarg value. Defaults to `doublet`(`mpl` only) """ image = None if output == 'text': return _text_circuit_drawer(circuit, filename=filename, line_length=line_length, reverse_bits=reverse_bits, plotbarriers=plot_barriers, justify=justify) elif output == 'latex': image = _latex_circuit_drawer(circuit, scale=scale, filename=filename, style=style, plot_barriers=plot_barriers, reverse_bits=reverse_bits, justify=justify) elif output == 'latex_source': return _generate_latex_source(circuit, filename=filename, scale=scale, style=style, plot_barriers=plot_barriers, reverse_bits=reverse_bits, justify=justify) elif output == 'mpl': image = _matplotlib_circuit_drawer(circuit, scale=scale, filename=filename, style=style, plot_barriers=plot_barriers, reverse_bits=reverse_bits, justify=justify) else: raise exceptions.VisualizationError( 'Invalid output type %s selected. The only valid choices ' 'are latex, latex_source, text, and mpl' % output) if image and interactive: image.show() return image
Draws a circuit using ascii art. Args: circuit ( QuantumCircuit ): Input circuit filename ( str ): optional filename to write the result line_length ( int ): Optional. Breaks the circuit drawing to this length. This useful when the drawing does not fit in the console. If None ( default ) it will try to guess the console width using shutil. get_terminal_size (). If you don t want pagination at all set line_length = - 1. reverse_bits ( bool ): Rearrange the bits in reverse order. plotbarriers ( bool ): Draws the barriers when they are there. justify ( str ): left right or none. Defaults to left. Says how the circuit should be justified. vertically_compressed ( bool ): Default is True. It merges the lines so the drawing will take less vertical room. Returns: TextDrawing: An instances that when printed draws the circuit in ascii art.
def _text_circuit_drawer(circuit, filename=None, line_length=None, reverse_bits=False, plotbarriers=True, justify=None, vertically_compressed=True): """ Draws a circuit using ascii art. Args: circuit (QuantumCircuit): Input circuit filename (str): optional filename to write the result line_length (int): Optional. Breaks the circuit drawing to this length. This useful when the drawing does not fit in the console. If None (default), it will try to guess the console width using shutil.get_terminal_size(). If you don't want pagination at all, set line_length=-1. reverse_bits (bool): Rearrange the bits in reverse order. plotbarriers (bool): Draws the barriers when they are there. justify (str) : `left`, `right` or `none`. Defaults to `left`. Says how the circuit should be justified. vertically_compressed (bool): Default is `True`. It merges the lines so the drawing will take less vertical room. Returns: TextDrawing: An instances that, when printed, draws the circuit in ascii art. """ qregs, cregs, ops = utils._get_layered_instructions(circuit, reverse_bits=reverse_bits, justify=justify) text_drawing = _text.TextDrawing(qregs, cregs, ops) text_drawing.plotbarriers = plotbarriers text_drawing.line_length = line_length text_drawing.vertically_compressed = vertically_compressed if filename: text_drawing.dump(filename) return text_drawing
Draw a quantum circuit based on latex ( Qcircuit package )
def _latex_circuit_drawer(circuit, scale=0.7, filename=None, style=None, plot_barriers=True, reverse_bits=False, justify=None): """Draw a quantum circuit based on latex (Qcircuit package) Requires version >=2.6.0 of the qcircuit LaTeX package. Args: circuit (QuantumCircuit): a quantum circuit scale (float): scaling factor filename (str): file path to save image to style (dict or str): dictionary of style or file name of style file reverse_bits (bool): When set to True reverse the bit order inside registers for the output visualization. plot_barriers (bool): Enable/disable drawing barriers in the output circuit. Defaults to True. justify (str) : `left`, `right` or `none`. Defaults to `left`. Says how the circuit should be justified. Returns: PIL.Image: an in-memory representation of the circuit diagram Raises: OSError: usually indicates that ```pdflatex``` or ```pdftocairo``` is missing. CalledProcessError: usually points errors during diagram creation. """ tmpfilename = 'circuit' with tempfile.TemporaryDirectory() as tmpdirname: tmppath = os.path.join(tmpdirname, tmpfilename + '.tex') _generate_latex_source(circuit, filename=tmppath, scale=scale, style=style, plot_barriers=plot_barriers, reverse_bits=reverse_bits, justify=justify) image = None try: subprocess.run(["pdflatex", "-halt-on-error", "-output-directory={}".format(tmpdirname), "{}".format(tmpfilename + '.tex')], stdout=subprocess.PIPE, stderr=subprocess.DEVNULL, check=True) except OSError as ex: if ex.errno == errno.ENOENT: logger.warning('WARNING: Unable to compile latex. ' 'Is `pdflatex` installed? ' 'Skipping latex circuit drawing...') raise except subprocess.CalledProcessError as ex: with open('latex_error.log', 'wb') as error_file: error_file.write(ex.stdout) logger.warning('WARNING Unable to compile latex. ' 'The output from the pdflatex command can ' 'be found in latex_error.log') raise else: try: base = os.path.join(tmpdirname, tmpfilename) subprocess.run(["pdftocairo", "-singlefile", "-png", "-q", base + '.pdf', base]) image = Image.open(base + '.png') image = utils._trim(image) os.remove(base + '.png') if filename: image.save(filename, 'PNG') except OSError as ex: if ex.errno == errno.ENOENT: logger.warning('WARNING: Unable to convert pdf to image. ' 'Is `poppler` installed? ' 'Skipping circuit drawing...') raise return image
Convert QuantumCircuit to LaTeX string.
def _generate_latex_source(circuit, filename=None, scale=0.7, style=None, reverse_bits=False, plot_barriers=True, justify=None): """Convert QuantumCircuit to LaTeX string. Args: circuit (QuantumCircuit): input circuit scale (float): image scaling filename (str): optional filename to write latex style (dict or str): dictionary of style or file name of style file reverse_bits (bool): When set to True reverse the bit order inside registers for the output visualization. plot_barriers (bool): Enable/disable drawing barriers in the output circuit. Defaults to True. justify (str) : `left`, `right` or `none`. Defaults to `left`. Says how the circuit should be justified. Returns: str: Latex string appropriate for writing to file. """ qregs, cregs, ops = utils._get_layered_instructions(circuit, reverse_bits=reverse_bits, justify=justify) qcimg = _latex.QCircuitImage(qregs, cregs, ops, scale, style=style, plot_barriers=plot_barriers, reverse_bits=reverse_bits) latex = qcimg.latex() if filename: with open(filename, 'w') as latex_file: latex_file.write(latex) return latex
Draw a quantum circuit based on matplotlib. If %matplotlib inline is invoked in a Jupyter notebook it visualizes a circuit inline. We recommend %config InlineBackend. figure_format = svg for the inline visualization.
def _matplotlib_circuit_drawer(circuit, scale=0.7, filename=None, style=None, plot_barriers=True, reverse_bits=False, justify=None): """Draw a quantum circuit based on matplotlib. If `%matplotlib inline` is invoked in a Jupyter notebook, it visualizes a circuit inline. We recommend `%config InlineBackend.figure_format = 'svg'` for the inline visualization. Args: circuit (QuantumCircuit): a quantum circuit scale (float): scaling factor filename (str): file path to save image to style (dict or str): dictionary of style or file name of style file reverse_bits (bool): When set to True reverse the bit order inside registers for the output visualization. plot_barriers (bool): Enable/disable drawing barriers in the output circuit. Defaults to True. justify (str) : `left`, `right` or `none`. Defaults to `left`. Says how the circuit should be justified. Returns: matplotlib.figure: a matplotlib figure object for the circuit diagram """ qregs, cregs, ops = utils._get_layered_instructions(circuit, reverse_bits=reverse_bits, justify=justify) qcd = _matplotlib.MatplotlibDrawer(qregs, cregs, ops, scale=scale, style=style, plot_barriers=plot_barriers, reverse_bits=reverse_bits) return qcd.draw(filename)
Return a random quantum state from the uniform ( Haar ) measure on state space.
def random_state(dim, seed=None): """ Return a random quantum state from the uniform (Haar) measure on state space. Args: dim (int): the dim of the state spaxe seed (int): Optional. To set a random seed. Returns: ndarray: state(2**num) a random quantum state. """ if seed is None: seed = np.random.randint(0, np.iinfo(np.int32).max) rng = np.random.RandomState(seed) # Random array over interval (0, 1] x = rng.rand(dim) x += x == 0 x = -np.log(x) sumx = sum(x) phases = rng.rand(dim)*2.0*np.pi return np.sqrt(x/sumx)*np.exp(1j*phases)
Return a random dim x dim unitary Operator from the Haar measure.
def random_unitary(dim, seed=None): """ Return a random dim x dim unitary Operator from the Haar measure. Args: dim (int): the dim of the state space. seed (int): Optional. To set a random seed. Returns: Operator: (dim, dim) unitary operator. Raises: QiskitError: if dim is not a positive power of 2. """ if dim == 0 or not math.log2(dim).is_integer(): raise QiskitError("Desired unitary dimension not a positive power of 2.") matrix = np.zeros([dim, dim], dtype=complex) for j in range(dim): if j == 0: a = random_state(dim, seed) else: a = random_state(dim) matrix[:, j] = np.copy(a) # Grahm-Schmidt Orthogonalize i = j-1 while i >= 0: dc = np.vdot(matrix[:, i], a) matrix[:, j] = matrix[:, j]-dc*matrix[:, i] i = i - 1 # normalize matrix[:, j] = matrix[:, j] * (1.0 / np.sqrt(np.vdot(matrix[:, j], matrix[:, j]))) return Operator(matrix)
Generate a random density matrix rho.
def random_density_matrix(length, rank=None, method='Hilbert-Schmidt', seed=None): """ Generate a random density matrix rho. Args: length (int): the length of the density matrix. rank (int or None): the rank of the density matrix. The default value is full-rank. method (string): the method to use. 'Hilbert-Schmidt': sample rho from the Hilbert-Schmidt metric. 'Bures': sample rho from the Bures metric. seed (int): Optional. To set a random seed. Returns: ndarray: rho (length, length) a density matrix. Raises: QiskitError: if the method is not valid. """ if method == 'Hilbert-Schmidt': return __random_density_hs(length, rank, seed) elif method == 'Bures': return __random_density_bures(length, rank, seed) else: raise QiskitError('Error: unrecognized method {}'.format(method))
Return a normally distributed complex random matrix.
def __ginibre_matrix(nrow, ncol=None, seed=None): """ Return a normally distributed complex random matrix. Args: nrow (int): number of rows in output matrix. ncol (int): number of columns in output matrix. seed (int): Optional. To set a random seed. Returns: ndarray: A complex rectangular matrix where each real and imaginary entry is sampled from the normal distribution. """ if ncol is None: ncol = nrow if seed is not None: np.random.seed(seed) G = np.random.normal(size=(nrow, ncol)) + \ np.random.normal(size=(nrow, ncol)) * 1j return G
Generate a random density matrix from the Hilbert - Schmidt metric.
def __random_density_hs(N, rank=None, seed=None): """ Generate a random density matrix from the Hilbert-Schmidt metric. Args: N (int): the length of the density matrix. rank (int or None): the rank of the density matrix. The default value is full-rank. seed (int): Optional. To set a random seed. Returns: ndarray: rho (N,N a density matrix. """ G = __ginibre_matrix(N, rank, seed) G = G.dot(G.conj().T) return G / np.trace(G)
Generate a random density matrix from the Bures metric.
def __random_density_bures(N, rank=None, seed=None): """ Generate a random density matrix from the Bures metric. Args: N (int): the length of the density matrix. rank (int or None): the rank of the density matrix. The default value is full-rank. seed (int): Optional. To set a random seed. Returns: ndarray: rho (N,N) a density matrix. """ P = np.eye(N) + random_unitary(N).data G = P.dot(__ginibre_matrix(N, rank, seed)) G = G.dot(G.conj().T) return G / np.trace(G)
Return the corresponding OPENQASM string.
def qasm(self, prec=15): """Return the corresponding OPENQASM string.""" string = "" for children in self.children: string += " " + children.qasm(prec) + "\n" return string
Return a list of custom gate names in this gate body.
def calls(self): """Return a list of custom gate names in this gate body.""" lst = [] for children in self.children: if children.type == "custom_unitary": lst.append(children.name) return lst
Return the corresponding OPENQASM string.
def qasm(self, prec=15): """Return the corresponding OPENQASM string.""" if self.value == pi: return "pi" return ccode(self.value, precision=prec)
gate sdg a { u1 ( - pi/ 2 ) a ; }
def _define(self): """ gate sdg a { u1(-pi/2) a; } """ definition = [] q = QuantumRegister(1, "q") rule = [ (U1Gate(-pi/2), [q[0]], []) ] for inst in rule: definition.append(inst) self.definition = definition
Return the composition channel self∘other.
def compose(self, other, qargs=None, front=False): """Return the composition channel self∘other. Args: other (QuantumChannel): a quantum channel. qargs (list): a list of subsystem positions to compose other on. front (bool): If False compose in standard order other(self(input)) otherwise compose in reverse order self(other(input)) [default: False] Returns: Chi: The composition channel as a Chi object. Raises: QiskitError: if other is not a QuantumChannel subclass, or has incompatible dimensions. """ if qargs is not None: return Chi( SuperOp(self).compose(other, qargs=qargs, front=front)) # Convert other to Choi since we convert via Choi if not isinstance(other, Choi): other = Choi(other) # Check dimensions match up if front and self._input_dim != other._output_dim: raise QiskitError( 'input_dim of self must match output_dim of other') if not front and self._output_dim != other._input_dim: raise QiskitError( 'input_dim of other must match output_dim of self') # Since we cannot directly add two channels in the Chi # representation we convert to the Choi representation return Chi(Choi(self).compose(other, front=front))
The matrix power of the channel.
def power(self, n): """The matrix power of the channel. Args: n (int): compute the matrix power of the superoperator matrix. Returns: Chi: the matrix power of the SuperOp converted to a Chi channel. Raises: QiskitError: if the input and output dimensions of the QuantumChannel are not equal, or the power is not an integer. """ if n > 0: return super().power(n) return Chi(SuperOp(self).power(n))
Return the QuantumChannel self + other.
def add(self, other): """Return the QuantumChannel self + other. Args: other (QuantumChannel): a quantum channel. Returns: Chi: the linear addition self + other as a Chi object. Raises: QiskitError: if other is not a QuantumChannel subclass, or has incompatible dimensions. """ if not isinstance(other, Chi): other = Chi(other) if self.dim != other.dim: raise QiskitError("other QuantumChannel dimensions are not equal") return Chi(self._data + other.data, self._input_dims, self._output_dims)
Return the QuantumChannel self + other.
def multiply(self, other): """Return the QuantumChannel self + other. Args: other (complex): a complex number. Returns: Chi: the scalar multiplication other * self as a Chi object. Raises: QiskitError: if other is not a valid scalar. """ if not isinstance(other, Number): raise QiskitError("other is not a number") return Chi(other * self._data, self._input_dims, self._output_dims)
Return the tensor product channel.
def _tensor_product(self, other, reverse=False): """Return the tensor product channel. Args: other (QuantumChannel): a quantum channel. reverse (bool): If False return self ⊗ other, if True return if True return (other ⊗ self) [Default: False Returns: Chi: the tensor product channel as a Chi object. Raises: QiskitError: if other is not a QuantumChannel subclass. """ if not isinstance(other, Chi): other = Chi(other) if reverse: input_dims = self.input_dims() + other.input_dims() output_dims = self.output_dims() + other.output_dims() data = np.kron(other.data, self._data) else: input_dims = other.input_dims() + self.input_dims() output_dims = other.output_dims() + self.output_dims() data = np.kron(self._data, other.data) return Chi(data, input_dims, output_dims)
Return the conjugate of the QuantumChannel.
def conjugate(self): """Return the conjugate of the QuantumChannel.""" return SuperOp( np.conj(self._data), self.input_dims(), self.output_dims())
Return the transpose of the QuantumChannel.
def transpose(self): """Return the transpose of the QuantumChannel.""" return SuperOp( np.transpose(self._data), input_dims=self.output_dims(), output_dims=self.input_dims())
Return the composition channel self∘other.
def compose(self, other, qargs=None, front=False): """Return the composition channel self∘other. Args: other (QuantumChannel): a quantum channel. qargs (list): a list of subsystem positions to compose other on. front (bool): If False compose in standard order other(self(input)) otherwise compose in reverse order self(other(input)) [default: False] Returns: SuperOp: The composition channel as a SuperOp object. Raises: QiskitError: if other is not a QuantumChannel subclass, or has incompatible dimensions. """ # Convert other to SuperOp if not isinstance(other, SuperOp): other = SuperOp(other) # Check dimensions are compatible if front and self.input_dims(qargs=qargs) != other.output_dims(): raise QiskitError( 'output_dims of other must match subsystem input_dims') if not front and self.output_dims(qargs=qargs) != other.input_dims(): raise QiskitError( 'input_dims of other must match subsystem output_dims') # Full composition of superoperators if qargs is None: if front: # Composition A(B(input)) return SuperOp( np.dot(self._data, other.data), input_dims=other.input_dims(), output_dims=self.output_dims()) # Composition B(A(input)) return SuperOp( np.dot(other.data, self._data), input_dims=self.input_dims(), output_dims=other.output_dims()) # Composition on subsystem return self._compose_subsystem(other, qargs, front)
Return the compose of a QuantumChannel with itself n times.
def power(self, n): """Return the compose of a QuantumChannel with itself n times. Args: n (int): compute the matrix power of the superoperator matrix. Returns: SuperOp: the n-times composition channel as a SuperOp object. Raises: QiskitError: if the input and output dimensions of the QuantumChannel are not equal, or the power is not an integer. """ if not isinstance(n, (int, np.integer)): raise QiskitError("Can only power with integer powers.") if self._input_dim != self._output_dim: raise QiskitError("Can only power with input_dim = output_dim.") # Override base class power so we can implement more efficiently # using Numpy.matrix_power return SuperOp( np.linalg.matrix_power(self._data, n), self.input_dims(), self.output_dims())
Return the QuantumChannel self + other.
def add(self, other): """Return the QuantumChannel self + other. Args: other (QuantumChannel): a quantum channel. Returns: SuperOp: the linear addition self + other as a SuperOp object. Raises: QiskitError: if other cannot be converted to a channel or has incompatible dimensions. """ # Convert other to SuperOp if not isinstance(other, SuperOp): other = SuperOp(other) if self.dim != other.dim: raise QiskitError("other QuantumChannel dimensions are not equal") return SuperOp(self._data + other.data, self.input_dims(), self.output_dims())
Return the QuantumChannel self + other.
def multiply(self, other): """Return the QuantumChannel self + other. Args: other (complex): a complex number. Returns: SuperOp: the scalar multiplication other * self as a SuperOp object. Raises: QiskitError: if other is not a valid scalar. """ if not isinstance(other, Number): raise QiskitError("other is not a number") return SuperOp(other * self._data, self.input_dims(), self.output_dims())
Evolve a quantum state by the QuantumChannel.
def _evolve(self, state, qargs=None): """Evolve a quantum state by the QuantumChannel. Args: state (QuantumState): The input statevector or density matrix. qargs (list): a list of QuantumState subsystem positions to apply the operator on. Returns: DensityMatrix: the output quantum state as a density matrix. Raises: QiskitError: if the operator dimension does not match the specified QuantumState subsystem dimensions. """ state = self._format_state(state, density_matrix=True) if qargs is None: if state.shape[0] != self._input_dim: raise QiskitError( "QuantumChannel input dimension is not equal to state dimension." ) shape_in = self._input_dim * self._input_dim shape_out = (self._output_dim, self._output_dim) # Return evolved density matrix return np.reshape( np.dot(self._data, np.reshape(state, shape_in, order='F')), shape_out, order='F') # Subsystem evolution return self._evolve_subsystem(state, qargs)
Return the composition channel.
def _compose_subsystem(self, other, qargs, front=False): """Return the composition channel.""" # Compute tensor contraction indices from qargs input_dims = list(self.input_dims()) output_dims = list(self.output_dims()) if front: num_indices = len(self.input_dims()) shift = 2 * len(self.output_dims()) right_mul = True for pos, qubit in enumerate(qargs): input_dims[qubit] = other._input_dims[pos] else: num_indices = len(self.output_dims()) shift = 0 right_mul = False for pos, qubit in enumerate(qargs): output_dims[qubit] = other._output_dims[pos] # Reshape current matrix # Note that we must reverse the subsystem dimension order as # qubit 0 corresponds to the right-most position in the tensor # product, which is the last tensor wire index. tensor = np.reshape(self.data, self._shape) mat = np.reshape(other.data, other._shape) # Add first set of indicies indices = [2 * num_indices - 1 - qubit for qubit in qargs ] + [num_indices - 1 - qubit for qubit in qargs] final_shape = [np.product(output_dims)**2, np.product(input_dims)**2] data = np.reshape( self._einsum_matmul(tensor, mat, indices, shift, right_mul), final_shape) return SuperOp(data, input_dims, output_dims)
Evolve a quantum state by the operator.
def _evolve_subsystem(self, state, qargs): """Evolve a quantum state by the operator. Args: state (QuantumState): The input statevector or density matrix. qargs (list): a list of QuantumState subsystem positions to apply the operator on. Returns: QuantumState: the output quantum state. Raises: QiskitError: if the operator dimension does not match the specified QuantumState subsystem dimensions. """ mat = np.reshape(self.data, self._shape) # Hack to assume state is a N-qubit state until a proper class for states # is in place state_size = len(state) state_dims = self._automatic_dims(None, state_size) if self.input_dims() != len(qargs) * (2, ): raise QiskitError( "Channel input dimensions are not compatible with state subsystem dimensions." ) # Return evolved density matrix tensor = np.reshape(state, 2 * state_dims) num_inidices = len(state_dims) indices = [num_inidices - 1 - qubit for qubit in qargs ] + [2 * num_inidices - 1 - qubit for qubit in qargs] tensor = self._einsum_matmul(tensor, mat, indices) return np.reshape(tensor, [state_size, state_size])
Convert a QuantumCircuit or Instruction to a SuperOp.
def _instruction_to_superop(cls, instruction): """Convert a QuantumCircuit or Instruction to a SuperOp.""" # Convert circuit to an instruction if isinstance(instruction, QuantumCircuit): instruction = instruction.to_instruction() # Initialize an identity superoperator of the correct size # of the circuit op = SuperOp(np.eye(4 ** instruction.num_qubits)) op._append_instruction(instruction) return op
Update the current Operator by apply an instruction.
def _append_instruction(self, obj, qargs=None): """Update the current Operator by apply an instruction.""" if isinstance(obj, Instruction): chan = None if obj.name == 'reset': # For superoperator evolution we can simulate a reset as # a non-unitary supeorperator matrix chan = SuperOp( np.array([[1, 0, 0, 1], [0, 0, 0, 0], [0, 0, 0, 0], [0, 0, 0, 0]])) if obj.name == 'kraus': kraus = obj.params dim = len(kraus[0]) chan = SuperOp(_to_superop('Kraus', (kraus, None), dim, dim)) elif hasattr(obj, 'to_matrix'): # If instruction is a gate first we see if it has a # `to_matrix` definition and if so use that. try: kraus = [obj.to_matrix()] dim = len(kraus[0]) chan = SuperOp( _to_superop('Kraus', (kraus, None), dim, dim)) except QiskitError: pass if chan is not None: # Perform the composition and inplace update the current state # of the operator op = self.compose(chan, qargs=qargs) self._data = op.data else: # If the instruction doesn't have a matrix defined we use its # circuit decomposition definition if it exists, otherwise we # cannot compose this gate and raise an error. if obj.definition is None: raise QiskitError('Cannot apply Instruction: {}'.format( obj.name)) for instr, qregs, cregs in obj.definition: if cregs: raise QiskitError( 'Cannot apply instruction with classical registers: {}' .format(instr.name)) # Get the integer position of the flat register new_qargs = [tup[1] for tup in qregs] self._append_instruction(instr, qargs=new_qargs) else: raise QiskitError('Input is not an instruction.')
Return a circuit with a barrier before last measurements.
def run(self, dag): """Return a circuit with a barrier before last measurements.""" # Collect DAG nodes which are followed only by barriers or other measures. final_op_types = ['measure', 'barrier'] final_ops = [] for candidate_node in dag.named_nodes(*final_op_types): is_final_op = True for _, child_successors in dag.bfs_successors(candidate_node): if any(suc.type == 'op' and suc.name not in final_op_types for suc in child_successors): is_final_op = False break if is_final_op: final_ops.append(candidate_node) if not final_ops: return dag # Create a layer with the barrier and add registers from the original dag. barrier_layer = DAGCircuit() for qreg in dag.qregs.values(): barrier_layer.add_qreg(qreg) for creg in dag.cregs.values(): barrier_layer.add_creg(creg) final_qubits = set(final_op.qargs[0] for final_op in final_ops) barrier_layer.apply_operation_back( Barrier(len(final_qubits)), list(final_qubits), []) # Preserve order of final ops collected earlier from the original DAG. ordered_final_nodes = [node for node in dag.topological_op_nodes() if node in set(final_ops)] # Move final ops to the new layer and append the new layer to the DAG. for final_node in ordered_final_nodes: barrier_layer.apply_operation_back(final_node.op, final_node.qargs, final_node.cargs) for final_op in final_ops: dag.remove_op_node(final_op) dag.extend_back(barrier_layer) # Merge the new barrier into any other barriers adjacent_pass = MergeAdjacentBarriers() return adjacent_pass.run(dag)
Convert a list of circuits into a qobj.
def circuits_to_qobj(circuits, qobj_header=None, qobj_id=None, backend_name=None, config=None, shots=None, max_credits=None, basis_gates=None, coupling_map=None, seed=None, memory=None): """Convert a list of circuits into a qobj. Args: circuits (list[QuantumCircuits] or QuantumCircuit): circuits to compile qobj_header (QobjHeader): header to pass to the results qobj_id (int): TODO: delete after qiskit-terra 0.8 backend_name (str): TODO: delete after qiskit-terra 0.8 config (dict): TODO: delete after qiskit-terra 0.8 shots (int): TODO: delete after qiskit-terra 0.8 max_credits (int): TODO: delete after qiskit-terra 0.8 basis_gates (str): TODO: delete after qiskit-terra 0.8 coupling_map (list): TODO: delete after qiskit-terra 0.8 seed (int): TODO: delete after qiskit-terra 0.8 memory (bool): TODO: delete after qiskit-terra 0.8 Returns: Qobj: the Qobj to be run on the backends """ warnings.warn('circuits_to_qobj is deprecated and will be removed in Qiskit Terra 0.9. ' 'Use qiskit.compiler.assemble() to serialize circuits into a qobj.', DeprecationWarning) qobj_header = qobj_header or QobjHeader() if backend_name: qobj_header.backend_name = backend_name if basis_gates: warnings.warn('basis_gates was unused and will be removed.', DeprecationWarning) if coupling_map: warnings.warn('coupling_map was unused and will be removed.', DeprecationWarning) qobj = assemble(experiments=circuits, qobj_id=qobj_id, qobj_header=qobj_header, shots=shots, memory=memory, max_credits=max_credits, seed_simulator=seed, config=config) return qobj
Expand 3 + qubit gates using their decomposition rules.
def run(self, dag): """Expand 3+ qubit gates using their decomposition rules. Args: dag(DAGCircuit): input dag Returns: DAGCircuit: output dag with maximum node degrees of 2 Raises: QiskitError: if a 3q+ gate is not decomposable """ for node in dag.threeQ_or_more_gates(): # TODO: allow choosing other possible decompositions rule = node.op.definition if not rule: raise QiskitError("Cannot unroll all 3q or more gates. " "No rule to expand instruction %s." % node.op.name) # hacky way to build a dag on the same register as the rule is defined # TODO: need anonymous rules to address wires by index decomposition = DAGCircuit() decomposition.add_qreg(rule[0][1][0][0]) for inst in rule: decomposition.apply_operation_back(*inst) decomposition = self.run(decomposition) # recursively unroll dag.substitute_node_with_dag(node, decomposition) return dag
Expand a given gate into its decomposition.
def run(self, dag): """Expand a given gate into its decomposition. Args: dag(DAGCircuit): input dag Returns: DAGCircuit: output dag where gate was expanded. """ # Walk through the DAG and expand each non-basis node for node in dag.op_nodes(self.gate): # opaque or built-in gates are not decomposable if not node.op.definition: continue # TODO: allow choosing among multiple decomposition rules rule = node.op.definition # hacky way to build a dag on the same register as the rule is defined # TODO: need anonymous rules to address wires by index decomposition = DAGCircuit() decomposition.add_qreg(rule[0][1][0][0]) if rule[0][2]: decomposition.add_creg(rule[0][2][0][0]) for inst in rule: decomposition.apply_operation_back(*inst) dag.substitute_node_with_dag(node, decomposition) return dag
Apply u2 to q.
def unitary(self, obj, qubits, label=None): """Apply u2 to q.""" if isinstance(qubits, QuantumRegister): qubits = qubits[:] return self.append(UnitaryGate(obj, label=label), qubits, [])
Calculate a subcircuit that implements this unitary.
def _define(self): """Calculate a subcircuit that implements this unitary.""" if self.num_qubits == 1: q = QuantumRegister(1, "q") angles = euler_angles_1q(self.to_matrix()) self.definition = [(U3Gate(*angles), [q[0]], [])] if self.num_qubits == 2: self.definition = two_qubit_kak(self.to_matrix())
Validate if the value is of the type of the schema s model.
def check_type(self, value, attr, data): """Validate if the value is of the type of the schema's model. Assumes the nested schema is a ``BaseSchema``. """ if self.many and not is_collection(value): raise self._not_expected_type( value, Iterable, fields=[self], field_names=attr, data=data) _check_type = super().check_type errors = [] values = value if self.many else [value] for idx, v in enumerate(values): try: _check_type(v, idx, values) except ValidationError as err: errors.append(err.messages) if errors: errors = errors if self.many else errors[0] raise ValidationError(errors) return value
Validate if it s a list of valid item - field values.
def check_type(self, value, attr, data): """Validate if it's a list of valid item-field values. Check if each element in the list can be validated by the item-field passed during construction. """ super().check_type(value, attr, data) errors = [] for idx, v in enumerate(value): try: self.container.check_type(v, idx, value) except ValidationError as err: errors.append(err.messages) if errors: raise ValidationError(errors) return value
Plot the directed acyclic graph ( dag ) to represent operation dependencies in a quantum circuit.
def dag_drawer(dag, scale=0.7, filename=None, style='color'): """Plot the directed acyclic graph (dag) to represent operation dependencies in a quantum circuit. Note this function leverages `pydot <https://github.com/erocarrera/pydot>`_ (via `nxpd <https://github.com/chebee7i/nxpd`_) to generate the graph, which means that having `Graphviz <https://www.graphviz.org/>`_ installed on your system is required for this to work. Args: dag (DAGCircuit): The dag to draw. scale (float): scaling factor filename (str): file path to save image to (format inferred from name) style (str): 'plain': B&W graph 'color' (default): color input/output/op nodes Returns: Ipython.display.Image: if in Jupyter notebook and not saving to file, otherwise None. Raises: VisualizationError: when style is not recognized. ImportError: when nxpd or pydot not installed. """ try: import nxpd import pydot # pylint: disable=unused-import except ImportError: raise ImportError("dag_drawer requires nxpd, pydot, and Graphviz. " "Run 'pip install nxpd pydot', and install graphviz") G = dag.to_networkx() G.graph['dpi'] = 100 * scale if style == 'plain': pass elif style == 'color': for node in G.nodes: n = G.nodes[node] n['label'] = node.name if node.type == 'op': n['color'] = 'blue' n['style'] = 'filled' n['fillcolor'] = 'lightblue' if node.type == 'in': n['color'] = 'black' n['style'] = 'filled' n['fillcolor'] = 'green' if node.type == 'out': n['color'] = 'black' n['style'] = 'filled' n['fillcolor'] = 'red' for e in G.edges(data=True): e[2]['label'] = e[2]['name'] else: raise VisualizationError("Unrecognized style for the dag_drawer.") if filename: show = False elif ('ipykernel' in sys.modules) and ('spyder' not in sys.modules): show = 'ipynb' else: show = True return nxpd.draw(G, filename=filename, show=show)
Set the absolute tolerence parameter for float comparisons.
def _atol(self, atol): """Set the absolute tolerence parameter for float comparisons.""" # NOTE: that this overrides the class value so applies to all # instances of the class. max_tol = self.__class__.MAX_TOL if atol < 0: raise QiskitError("Invalid atol: must be non-negative.") if atol > max_tol: raise QiskitError( "Invalid atol: must be less than {}.".format(max_tol)) self.__class__.ATOL = atol
Set the relative tolerence parameter for float comparisons.
def _rtol(self, rtol): """Set the relative tolerence parameter for float comparisons.""" # NOTE: that this overrides the class value so applies to all # instances of the class. max_tol = self.__class__.MAX_TOL if rtol < 0: raise QiskitError("Invalid rtol: must be non-negative.") if rtol > max_tol: raise QiskitError( "Invalid rtol: must be less than {}.".format(max_tol)) self.__class__.RTOL = rtol
Reshape input and output dimensions of operator.
def _reshape(self, input_dims=None, output_dims=None): """Reshape input and output dimensions of operator. Arg: input_dims (tuple): new subsystem input dimensions. output_dims (tuple): new subsystem output dimensions. Returns: Operator: returns self with reshaped input and output dimensions. Raises: QiskitError: if combined size of all subsystem input dimension or subsystem output dimensions is not constant. """ if input_dims is not None: if np.product(input_dims) != self._input_dim: raise QiskitError( "Reshaped input_dims are incompatible with combined input dimension." ) self._input_dims = tuple(input_dims) if output_dims is not None: if np.product(output_dims) != self._output_dim: raise QiskitError( "Reshaped input_dims are incompatible with combined input dimension." ) self._output_dims = tuple(output_dims) return self
Return tuple of input dimension for specified subsystems.
def input_dims(self, qargs=None): """Return tuple of input dimension for specified subsystems.""" if qargs is None: return self._input_dims return tuple(self._input_dims[i] for i in qargs)
Return tuple of output dimension for specified subsystems.
def output_dims(self, qargs=None): """Return tuple of output dimension for specified subsystems.""" if qargs is None: return self._output_dims return tuple(self._output_dims[i] for i in qargs)
Make a copy of current operator.
def copy(self): """Make a copy of current operator.""" # pylint: disable=no-value-for-parameter # The constructor of subclasses from raw data should be a copy return self.__class__(self.data, self.input_dims(), self.output_dims())
Return the compose of a operator with itself n times.
def power(self, n): """Return the compose of a operator with itself n times. Args: n (int): the number of times to compose with self (n>0). Returns: BaseOperator: the n-times composed operator. Raises: QiskitError: if the input and output dimensions of the operator are not equal, or the power is not a positive integer. """ # NOTE: if a subclass can have negative or non-integer powers # this method should be overriden in that class. if not isinstance(n, (int, np.integer)) or n < 1: raise QiskitError("Can only power with positive integer powers.") if self._input_dim != self._output_dim: raise QiskitError("Can only power with input_dim = output_dim.") ret = self.copy() for _ in range(1, n): ret = ret.compose(self) return ret
Check if input dimension corresponds to qubit subsystems.
def _automatic_dims(cls, dims, size): """Check if input dimension corresponds to qubit subsystems.""" if dims is None: dims = size elif np.product(dims) != size: raise QiskitError("dimensions do not match size.") if isinstance(dims, (int, np.integer)): num_qubits = int(np.log2(dims)) if 2 ** num_qubits == size: return num_qubits * (2,) return (dims,) return tuple(dims)
Perform a contraction using Numpy. einsum
def _einsum_matmul(cls, tensor, mat, indices, shift=0, right_mul=False): """Perform a contraction using Numpy.einsum Args: tensor (np.array): a vector or matrix reshaped to a rank-N tensor. mat (np.array): a matrix reshaped to a rank-2M tensor. indices (list): tensor indices to contract with mat. shift (int): shift for indicies of tensor to contract [Default: 0]. right_mul (bool): if True right multiply tensor by mat (else left multiply) [Default: False]. Returns: Numpy.ndarray: the matrix multiplied rank-N tensor. Raises: QiskitError: if mat is not an even rank tensor. """ rank = tensor.ndim rank_mat = mat.ndim if rank_mat % 2 != 0: raise QiskitError( "Contracted matrix must have an even number of indices.") # Get einsum indices for tensor indices_tensor = list(range(rank)) for j, index in enumerate(indices): indices_tensor[index + shift] = rank + j # Get einsum indces for mat mat_contract = list(reversed(range(rank, rank + len(indices)))) mat_free = [index + shift for index in reversed(indices)] if right_mul: indices_mat = mat_contract + mat_free else: indices_mat = mat_free + mat_contract return np.einsum(tensor, indices_tensor, mat, indices_mat)
Override _deserialize for customizing the exception raised.
def _deserialize(self, value, attr, data): """Override ``_deserialize`` for customizing the exception raised.""" try: return super()._deserialize(value, attr, data) except ValidationError as ex: if 'deserialization_schema_selector' in ex.messages[0]: ex.messages[0] = 'Cannot find a valid schema among the choices' raise
Override _serialize for customizing the exception raised.
def _serialize(self, value, key, obj): """Override ``_serialize`` for customizing the exception raised.""" try: return super()._serialize(value, key, obj) except TypeError as ex: if 'serialization_schema_selector' in str(ex): raise ValidationError('Data from an invalid schema') raise
Check if at least one of the possible choices validates the value.
def check_type(self, value, attr, data): """Check if at least one of the possible choices validates the value. Possible choices are assumed to be ``ModelTypeValidator`` fields. """ for field in self.choices: if isinstance(field, ModelTypeValidator): try: return field.check_type(value, attr, data) except ValidationError: pass raise self._not_expected_type( value, [field.__class__ for field in self.choices], fields=[self], field_names=attr, data=data)
Return the state fidelity between two quantum states.
def state_fidelity(state1, state2): """Return the state fidelity between two quantum states. Either input may be a state vector, or a density matrix. The state fidelity (F) for two density matrices is defined as:: F(rho1, rho2) = Tr[sqrt(sqrt(rho1).rho2.sqrt(rho1))] ^ 2 For a pure state and mixed state the fidelity is given by:: F(|psi1>, rho2) = <psi1|rho2|psi1> For two pure states the fidelity is given by:: F(|psi1>, |psi2>) = |<psi1|psi2>|^2 Args: state1 (array_like): a quantum state vector or density matrix. state2 (array_like): a quantum state vector or density matrix. Returns: array_like: The state fidelity F(state1, state2). """ # convert input to numpy arrays s1 = np.array(state1) s2 = np.array(state2) # fidelity of two state vectors if s1.ndim == 1 and s2.ndim == 1: return np.abs(s2.conj().dot(s1)) ** 2 # fidelity of vector and density matrix elif s1.ndim == 1: # psi = s1, rho = s2 return np.abs(s1.conj().dot(s2).dot(s1)) elif s2.ndim == 1: # psi = s2, rho = s1 return np.abs(s2.conj().dot(s1).dot(s2)) # fidelity of two density matrices s1sq = _funm_svd(s1, np.sqrt) s2sq = _funm_svd(s2, np.sqrt) return np.linalg.norm(s1sq.dot(s2sq), ord='nuc') ** 2
Apply real scalar function to singular values of a matrix.
def _funm_svd(a, func): """Apply real scalar function to singular values of a matrix. Args: a (array_like): (N, N) Matrix at which to evaluate the function. func (callable): Callable object that evaluates a scalar function f. Returns: ndarray: funm (N, N) Value of the matrix function specified by func evaluated at `A`. """ U, s, Vh = la.svd(a, lapack_driver='gesvd') S = np.diag(func(s)) return U.dot(S).dot(Vh)
If dag is mapped to coupling_map the property is_swap_mapped is set to True ( or to False otherwise ).
def run(self, dag): """ If `dag` is mapped to `coupling_map`, the property `is_swap_mapped` is set to True (or to False otherwise). Args: dag (DAGCircuit): DAG to map. """ if self.layout is None: if self.property_set["layout"]: self.layout = self.property_set["layout"] else: self.layout = Layout.generate_trivial_layout(*dag.qregs.values()) self.property_set['is_swap_mapped'] = True for gate in dag.twoQ_gates(): physical_q0 = self.layout[gate.qargs[0]] physical_q1 = self.layout[gate.qargs[1]] if self.coupling_map.distance(physical_q0, physical_q1) != 1: self.property_set['is_swap_mapped'] = False return
Take a statevector snapshot of the internal simulator representation. Works on all qubits and prevents reordering ( like barrier ).
def snapshot(self, label, snapshot_type='statevector', qubits=None, params=None): """Take a statevector snapshot of the internal simulator representation. Works on all qubits, and prevents reordering (like barrier). For other types of snapshots use the Snapshot extension directly. Args: label (str): a snapshot label to report the result snapshot_type (str): the type of the snapshot. qubits (list or None): the qubits to apply snapshot to [Default: None]. params (list or None): the parameters for snapshot_type [Default: None]. Returns: QuantumCircuit: with attached command Raises: ExtensionError: malformed command """ # Convert label to string for backwards compatibility if not isinstance(label, str): warnings.warn( "Snapshot label should be a string, " "implicit conversion is depreciated.", DeprecationWarning) label = str(label) # If no qubits are specified we add all qubits so it acts as a barrier # This is needed for full register snapshots like statevector if isinstance(qubits, QuantumRegister): qubits = qubits[:] if not qubits: tuples = [] if isinstance(self, QuantumCircuit): for register in self.qregs: tuples.append(register) if not tuples: raise ExtensionError('no qubits for snapshot') qubits = [] for tuple_element in tuples: if isinstance(tuple_element, QuantumRegister): for j in range(tuple_element.size): qubits.append((tuple_element, j)) else: qubits.append(tuple_element) return self.append( Snapshot( label, snapshot_type=snapshot_type, num_qubits=len(qubits), params=params), qubits)
Assemble a QasmQobjInstruction
def assemble(self): """Assemble a QasmQobjInstruction""" instruction = super().assemble() instruction.label = self._label instruction.snapshot_type = self._snapshot_type return instruction
Special case. Return self.
def inverse(self): """Special case. Return self.""" return Snapshot(self.num_qubits, self.num_clbits, self.params[0], self.params[1])
Set snapshot label to name
def label(self, name): """Set snapshot label to name Args: name (str or None): label to assign unitary Raises: TypeError: name is not string or None. """ if isinstance(name, str): self._label = name else: raise TypeError('label expects a string')
Return True if completely - positive trace - preserving ( CPTP ).
def is_cptp(self, atol=None, rtol=None): """Return True if completely-positive trace-preserving (CPTP).""" choi = _to_choi(self.rep, self._data, *self.dim) return self._is_cp_helper(choi, atol, rtol) and self._is_tp_helper( choi, atol, rtol)
Test if a channel is completely - positive ( CP )
def is_tp(self, atol=None, rtol=None): """Test if a channel is completely-positive (CP)""" choi = _to_choi(self.rep, self._data, *self.dim) return self._is_tp_helper(choi, atol, rtol)
Test if Choi - matrix is completely - positive ( CP )
def is_cp(self, atol=None, rtol=None): """Test if Choi-matrix is completely-positive (CP)""" choi = _to_choi(self.rep, self._data, *self.dim) return self._is_cp_helper(choi, atol, rtol)
Return True if QuantumChannel is a unitary channel.
def is_unitary(self, atol=None, rtol=None): """Return True if QuantumChannel is a unitary channel.""" try: op = self.to_operator() return op.is_unitary(atol=atol, rtol=rtol) except QiskitError: return False
Try to convert channel to a unitary representation Operator.
def to_operator(self): """Try to convert channel to a unitary representation Operator.""" mat = _to_operator(self.rep, self._data, *self.dim) return Operator(mat, self.input_dims(), self.output_dims())
Convert to a Kraus or UnitaryGate circuit instruction.
def to_instruction(self): """Convert to a Kraus or UnitaryGate circuit instruction. If the channel is unitary it will be added as a unitary gate, otherwise it will be added as a kraus simulator instruction. Returns: Instruction: A kraus instruction for the channel. Raises: QiskitError: if input data is not an N-qubit CPTP quantum channel. """ from qiskit.circuit.instruction import Instruction # Check if input is an N-qubit CPTP channel. n_qubits = int(np.log2(self._input_dim)) if self._input_dim != self._output_dim or 2**n_qubits != self._input_dim: raise QiskitError( 'Cannot convert QuantumChannel to Instruction: channel is not an N-qubit channel.' ) if not self.is_cptp(): raise QiskitError( 'Cannot convert QuantumChannel to Instruction: channel is not CPTP.' ) # Next we convert to the Kraus representation. Since channel is CPTP we know # that there is only a single set of Kraus operators kraus, _ = _to_kraus(self.rep, self._data, *self.dim) # If we only have a single Kraus operator then the channel is # a unitary channel so can be converted to a UnitaryGate. We do this by # converting to an Operator and using its to_instruction method if len(kraus) == 1: return Operator(kraus[0]).to_instruction() return Instruction('kraus', n_qubits, 0, kraus)
Test if a channel is completely - positive ( CP )
def _is_cp_helper(self, choi, atol, rtol): """Test if a channel is completely-positive (CP)""" if atol is None: atol = self._atol if rtol is None: rtol = self._rtol return is_positive_semidefinite_matrix(choi, rtol=rtol, atol=atol)
Test if Choi - matrix is trace - preserving ( TP )
def _is_tp_helper(self, choi, atol, rtol): """Test if Choi-matrix is trace-preserving (TP)""" if atol is None: atol = self._atol if rtol is None: rtol = self._rtol # Check if the partial trace is the identity matrix d_in, d_out = self.dim mat = np.trace( np.reshape(choi, (d_in, d_out, d_in, d_out)), axis1=1, axis2=3) return is_identity_matrix(mat, rtol=rtol, atol=atol)
Format input state so it is statevector or density matrix
def _format_state(self, state, density_matrix=False): """Format input state so it is statevector or density matrix""" state = np.array(state) shape = state.shape ndim = state.ndim if ndim > 2: raise QiskitError('Input state is not a vector or matrix.') # Flatten column-vector to vector if ndim == 2: if shape[1] != 1 and shape[1] != shape[0]: raise QiskitError('Input state is not a vector or matrix.') if shape[1] == 1: # flatten colum-vector to vector state = np.reshape(state, shape[0]) # Convert statevector to density matrix if required if density_matrix and ndim == 1: state = np.outer(state, np.transpose(np.conj(state))) return state