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def _best_subset(self, n_qubits): """Computes the qubit mapping with the best connectivity. Args: n_qubits (int): Number of subset qubits to consider. Returns: ndarray: Array of qubits to use for best connectivity mapping. """ if n_qubits == 1: ...
def is_cptp(self, atol=None, rtol=None): """Return True if completely-positive trace-preserving.""" if self._data[1] is not None: return False if atol is None: atol = self._atol if rtol is None: rtol = self._rtol accum = 0j for op in se...
def conjugate(self): """Return the conjugate of the QuantumChannel.""" kraus_l, kraus_r = self._data kraus_l = [k.conj() for k in kraus_l] if kraus_r is not None: kraus_r = [k.conj() for k in kraus_r] return Kraus((kraus_l, kraus_r), self.input_dims(), self.output_dim...
def transpose(self): """Return the transpose of the QuantumChannel.""" kraus_l, kraus_r = self._data kraus_l = [k.T for k in kraus_l] if kraus_r is not None: kraus_r = [k.T for k in kraus_r] return Kraus((kraus_l, kraus_r), input_dims=self.output_...
def compose(self, other, qargs=None, front=False): """Return the composition channel self∘other. Args: other (QuantumChannel): a quantum channel subclass. qargs (list): a list of subsystem positions to compose other on. front (bool): If False compose in standard orde...
def power(self, n): """The matrix power of the channel. Args: n (int): compute the matrix power of the superoperator matrix. Returns: Kraus: the matrix power of the SuperOp converted to a Kraus channel. Raises: QiskitError: if the input and output d...
def multiply(self, other): """Return the QuantumChannel self + other. Args: other (complex): a complex number. Returns: Kraus: the scalar multiplication other * self as a Kraus object. Raises: QiskitError: if other is not a valid scalar. """...
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. Retu...
def _tensor_product(self, other, reverse=False): """Return the tensor product channel. Args: other (QuantumChannel): a quantum channel subclass. reverse (bool): If False return self ⊗ other, if True return if True return (other ⊗ self) [Default: False...
def functional_pulse(func): """A decorator for generating SamplePulse from python callable. Args: func (callable): A function describing pulse envelope. Raises: PulseError: when invalid function is specified. """ @functools.wraps(func) def to_pulse(duration, *args, name=None, **k...
def real(self, nested_scope=None): """Return the correspond floating point number.""" operation = self.children[0].operation() lhs = self.children[1].real(nested_scope) rhs = self.children[2].real(nested_scope) return operation(lhs, rhs)
def sym(self, nested_scope=None): """Return the correspond symbolic number.""" operation = self.children[0].operation() lhs = self.children[1].sym(nested_scope) rhs = self.children[2].sym(nested_scope) return operation(lhs, rhs)
def barrier(self, *qargs): """Apply barrier to circuit. If qargs is None, applies to all the qbits. Args is a list of QuantumRegister or single qubits. For QuantumRegister, applies barrier to all the qubits in that register.""" qubits = [] qargs = _convert_to_bits(qargs, [qbit for qreg in self....
def average_data(counts, observable): """Compute the mean value of an diagonal observable. Takes in a diagonal observable in dictionary, list or matrix format and then calculates the sum_i value(i) P(i) where value(i) is the value of the observable for state i. Args: counts (dict): a dict ...
def _process_bit_id(self, node): """Process an Id or IndexedId node as a bit or register type. Return a list of tuples (Register,index). """ # pylint: disable=inconsistent-return-statements reg = None if node.name in self.dag.qregs: reg = self.dag.qregs[node....
def _process_custom_unitary(self, node): """Process a custom unitary node.""" name = node.name if node.arguments is not None: args = self._process_node(node.arguments) else: args = [] bits = [self._process_bit_id(node_element) for node_elem...
def _process_gate(self, node, opaque=False): """Process a gate node. If opaque is True, process the node as an opaque gate node. """ self.gates[node.name] = {} de_gate = self.gates[node.name] de_gate["print"] = True # default de_gate["opaque"] = opaque d...
def _process_cnot(self, node): """Process a CNOT gate node.""" id0 = self._process_bit_id(node.children[0]) id1 = self._process_bit_id(node.children[1]) if not(len(id0) == len(id1) or len(id0) == 1 or len(id1) == 1): raise QiskitError("internal error: qreg size mismatch", ...
def _process_measure(self, node): """Process a measurement node.""" id0 = self._process_bit_id(node.children[0]) id1 = self._process_bit_id(node.children[1]) if len(id0) != len(id1): raise QiskitError("internal error: reg size mismatch", "line=%s...
def _process_if(self, node): """Process an if node.""" creg_name = node.children[0].name creg = self.dag.cregs[creg_name] cval = node.children[1].value self.condition = (creg, cval) self._process_node(node.children[2]) self.condition = None
def _process_node(self, node): """Carry out the action associated with a node.""" if node.type == "program": self._process_children(node) elif node.type == "qreg": qreg = QuantumRegister(node.index, node.name) self.dag.add_qreg(qreg) elif node.type =...
def _create_dag_op(self, name, params, qargs): """ Create a DAG node out of a parsed AST op node. Args: name (str): operation name to apply to the dag. params (list): op parameters qargs (list(QuantumRegister, int)): qubits to attach to Raises: ...
def qasm(self, prec=15): """Return the corresponding OPENQASM string.""" return "measure " + self.children[0].qasm(prec) + " -> " + \ self.children[1].qasm(prec) + ";"
def ch_duration(self, *channels: List[Channel]) -> int: """Return duration of supplied channels. Args: *channels: Supplied channels """ return self.timeslots.ch_duration(*channels)
def ch_start_time(self, *channels: List[Channel]) -> int: """Return minimum start time for supplied channels. Args: *channels: Supplied channels """ return self.timeslots.ch_start_time(*channels)
def ch_stop_time(self, *channels: List[Channel]) -> int: """Return maximum start time for supplied channels. Args: *channels: Supplied channels """ return self.timeslots.ch_stop_time(*channels)
def _instructions(self, time: int = 0) -> Iterable[Tuple[int, 'Instruction']]: """Iterable for flattening Schedule tree. Args: time: Shifted time due to parent Yields: Tuple[int, ScheduleComponent]: Tuple containing time `ScheduleComponent` starts at and...
def to_string(self, indent): """Print with indent.""" ind = indent * ' ' print(ind, 'indexed_id', self.name, self.index)
def check_type(self, value, attr, data): """Validates a value against the correct type of the field. It calls ``_expected_types`` to get a list of valid types. Subclasses can do one of the following: 1. They can override the ``valid_types`` property with a tuple with t...
def dump_additional_data(self, valid_data, many, original_data): """Include unknown fields after dumping. Unknown fields are added with no processing at all. Args: valid_data (dict or list): data collected and returned by ``dump()``. many (bool): if True, data and origi...
def load_additional_data(self, valid_data, many, original_data): """Include unknown fields after load. Unknown fields are added with no processing at all. Args: valid_data (dict or list): validated data returned by ``load()``. many (bool): if True, data and original_dat...
def _create_validation_schema(schema_cls): """Create a patched Schema for validating models. Model validation is not part of Marshmallow. Schemas have a ``validate`` method but this delegates execution on ``load`` and discards the result. Similarly, ``load`` will call ``_deserialize`` o...
def _validate(instance): """Validate the internal representation of the instance.""" try: _ = instance.schema.validate(instance.to_dict()) except ValidationError as ex: raise ModelValidationError( ex.messages, ex.field_names, ex.fields, ex.data, **ex.kwarg...
def _validate_after_init(init_method): """Add validation after instantiation.""" @wraps(init_method) def _decorated(self, **kwargs): try: _ = self.shallow_schema.validate(kwargs) except ValidationError as ex: raise ModelValidationError( ...
def to_dict(self): """Serialize the model into a Python dict of simple types. Note that this method requires that the model is bound with ``@bind_schema``. """ try: data, _ = self.schema.dump(self) except ValidationError as ex: raise ModelValidati...
def from_dict(cls, dict_): """Deserialize a dict of simple types into an instance of this class. Note that this method requires that the model is bound with ``@bind_schema``. """ try: data, _ = cls.schema.load(dict_) except ValidationError as ex: ...
def qft(circ, q, n): """n-qubit QFT on q in circ.""" for j in range(n): for k in range(j): circ.cu1(math.pi / float(2**(j - k)), q[j], q[k]) circ.h(q[j])
def partial_trace(state, trace_systems, dimensions=None, reverse=True): """ Partial trace over subsystems of multi-partite matrix. Note that subsystems are ordered as rho012 = rho0(x)rho1(x)rho2. Args: state (matrix_like): a matrix NxN trace_systems (list(int)): a list of subsystems (s...
def __partial_trace_vec(vec, trace_systems, dimensions, reverse=True): """ Partial trace over subsystems of multi-partite vector. Args: vec (vector_like): complex vector N trace_systems (list(int)): a list of subsystems (starting from 0) to trace over. ...
def __partial_trace_mat(mat, trace_systems, dimensions, reverse=True): """ Partial trace over subsystems of multi-partite matrix. Note that subsystems are ordered as rho012 = rho0(x)rho1(x)rho2. Args: mat (matrix_like): a matrix NxN. trace_systems (list(int)): a list of subsystems (sta...
def vectorize(density_matrix, method='col'): """Flatten an operator to a vector in a specified basis. Args: density_matrix (ndarray): a density matrix. method (str): the method of vectorization. Allowed values are - 'col' (default) flattens to column-major vector. - 'row...
def devectorize(vectorized_mat, method='col'): """Devectorize a vectorized square matrix. Args: vectorized_mat (ndarray): a vectorized density matrix. method (str): the method of devectorization. Allowed values are - 'col' (default): flattens to column-major vector. - 'r...
def choi_to_rauli(choi, order=1): """ Convert a Choi-matrix to a Pauli-basis superoperator. Note that this function assumes that the Choi-matrix is defined in the standard column-stacking convention and is normalized to have trace 1. For a channel E this is defined as: choi = (I \\otimes E)(bel...
def chop(array, epsilon=1e-10): """ Truncate small values of a complex array. Args: array (array_like): array to truncte small values. epsilon (float): threshold. Returns: np.array: A new operator with small values set to zero. """ ret = np.array(array) if np.isrea...
def outer(vector1, vector2=None): """ Construct the outer product of two vectors. The second vector argument is optional, if absent the projector of the first vector will be returned. Args: vector1 (ndarray): the first vector. vector2 (ndarray): the (optional) second vector. R...
def random_unitary_matrix(dim, seed=None): """Deprecated in 0.8+ """ warnings.warn('The random_unitary_matrix() function in qiskit.tools.qi has been ' 'deprecated and will be removed in the future. Instead use ' 'the function in qiskit.quantum_info.random', ...
def random_density_matrix(length, rank=None, method='Hilbert-Schmidt', seed=None): """Deprecated in 0.8+ """ warnings.warn('The random_density_matrix() function in qiskit.tools.qi has been ' 'deprecated and will be removed in the future. Instead use ' 'the function in qis...
def concurrence(state): """Calculate the concurrence. Args: state (np.array): a quantum state (1x4 array) or a density matrix (4x4 array) Returns: float: concurrence. Raises: Exception: if attempted on more than two qubits. """ rho = np.array(st...
def shannon_entropy(pvec, base=2): """ Compute the Shannon entropy of a probability vector. The shannon entropy of a probability vector pv is defined as $H(pv) = - \\sum_j pv[j] log_b (pv[j])$ where $0 log_b 0 = 0$. Args: pvec (array_like): a probability vector. base (int): the bas...
def entropy(state): """ Compute the von-Neumann entropy of a quantum state. Args: state (array_like): a density matrix or state vector. Returns: float: The von-Neumann entropy S(rho). """ rho = np.array(state) if rho.ndim == 1: return 0 evals = np.maximum(np.li...
def mutual_information(state, d0, d1=None): """ Compute the mutual information of a bipartite state. Args: state (array_like): a bipartite state-vector or density-matrix. d0 (int): dimension of the first subsystem. d1 (int or None): dimension of the second subsystem. Returns: ...
def entanglement_of_formation(state, d0, d1=None): """ Compute the entanglement of formation of quantum state. The input quantum state must be either a bipartite state vector, or a 2-qubit density matrix. Args: state (array_like): (N) array_like or (4,4) array_like, a bipartite...
def __eof_qubit(rho): """ Compute the Entanglement of Formation of a 2-qubit density matrix. Args: rho ((array_like): (4,4) array_like, input density matrix. Returns: float: The entanglement of formation. """ c = concurrence(rho) c = 0.5 + 0.5 * np.sqrt(1 - c * c) retur...
def union(*schedules: List[Union[ScheduleComponent, Tuple[int, ScheduleComponent]]], name: str = None) -> Schedule: """Create a union (and also shift if desired) of all input `Schedule`s. Args: *schedules: Schedules to take the union of name: Name of the new schedule. Defaults to firs...
def flatten(schedule: ScheduleComponent, name: str = None) -> Schedule: """Create a flattened schedule. Args: schedule: Schedules to flatten name: Name of the new schedule. Defaults to first element of `schedules` """ if name is None: name = schedule.name return Schedule(*s...
def shift(schedule: ScheduleComponent, time: int, name: str = None) -> Schedule: """Return schedule shifted by `time`. Args: schedule: The schedule to shift time: The time to shift by name: Name of shifted schedule. Defaults to name of `schedule` """ if name is None: nam...
def insert(parent: ScheduleComponent, time: int, child: ScheduleComponent, name: str = None) -> Schedule: """Return a new schedule with the `child` schedule inserted into the `parent` at `start_time`. Args: parent: Schedule to be inserted into time: Time to be inserted defined with r...
def append(parent: ScheduleComponent, child: ScheduleComponent, name: str = None) -> Schedule: r"""Return a new schedule with by appending `child` to `parent` at the last time of the `parent` schedule's channels over the intersection of the parent and child schedule's channels. $t =...
def u3(self, theta, phi, lam, q): """Apply u3 to q.""" return self.append(U3Gate(theta, phi, lam), [q], [])
def status(self): """Return backend status. Returns: BackendStatus: the status of the backend. """ return BackendStatus(backend_name=self.name(), backend_version=__version__, operational=True, ...
def start(self, iterations): """Start the progress bar. Parameters: iterations (int): Number of iterations. """ self.touched = True self.iter = int(iterations) self.t_start = time.time()
def time_remaining_est(self, completed_iter): """Estimate the remaining time left. Parameters: completed_iter (int): Number of iterations completed. Returns: est_time: Estimated time remaining. """ if completed_iter: t_r_est = (time.time() - ...
def run(self, dag): """Run the CommutativeCancellation pass on a dag Args: dag (DAGCircuit): the DAG to be optimized. Returns: DAGCircuit: the optimized DAG. Raises: TranspilerError: when the 1 qubit rotation gates are not found """ ...
def _experiments_to_circuits(qobj): """Return a list of QuantumCircuit object(s) from a qobj Args: qobj (Qobj): The Qobj object to convert to QuantumCircuits Returns: list: A list of QuantumCircuit objects from the qobj """ if qobj.experiments: circuits = [] for x i...
def disassemble(qobj): """Dissasemble a qobj and return the circuits, run_config, and user header Args: qobj (Qobj): The input qobj object to dissasemble Returns: circuits (list): A list of quantum circuits run_config (dict): The dist of the run config user_qobj_header (dict...
def hamming_distance(str1, str2): """Calculate the Hamming distance between two bit strings Args: str1 (str): First string. str2 (str): Second string. Returns: int: Distance between strings. Raises: VisualizationError: Strings not same length """ if len(str1) != ...
def plot_histogram(data, figsize=(7, 5), color=None, number_to_keep=None, sort='asc', target_string=None, legend=None, bar_labels=True, title=None): """Plot a histogram of data. Args: data (list or dict): This is either a list of dictionaries or a single ...
def quaternion_from_axis_rotation(angle, axis): """Return quaternion for rotation about given axis. Args: angle (float): Angle in radians. axis (str): Axis for rotation Returns: Quaternion: Quaternion for axis rotation. Raises: ValueError: Invalid input axis. """ ...
def quaternion_from_euler(angles, order='yzy'): """Generate a quaternion from a set of Euler angles. Args: angles (array_like): Array of Euler angles. order (str): Order of Euler rotations. 'yzy' is default. Returns: Quaternion: Quaternion representation of Euler rotation. """...
def normalize(self, inplace=False): """Normalizes a Quaternion to unit length so that it represents a valid rotation. Args: inplace (bool): Do an inplace normalization. Returns: Quaternion: Normalized quaternion. """ if inplace: nrm =...
def to_matrix(self): """Converts a unit-length quaternion to a rotation matrix. Returns: ndarray: Rotation matrix. """ w, x, y, z = self.normalize().data # pylint: disable=C0103 mat = np.array([ [1-2*y**2-2*z**2, 2*x*y-2*z*w, 2*x*z+2*y*w], [2...
def to_zyz(self): """Converts a unit-length quaternion to a sequence of ZYZ Euler angles. Returns: ndarray: Array of Euler angles. """ mat = self.to_matrix() euler = np.zeros(3, dtype=float) if mat[2, 2] < 1: if mat[2, 2] > -1: ...
def process_data(data, number_to_keep): """ Prepare received data for representation. Args: data (dict): values to represent (ex. {'001' : 130}) number_to_keep (int): number of elements to show individually. Returns: dict: processed data to show. """ re...
def iplot_histogram(data, figsize=None, number_to_keep=None, sort='asc', legend=None): """ Create a histogram representation. Graphical representation of the input array using a vertical bars style graph. Args: data (list or dict): This is either a list of ...
def check_type(self, value, attr, data): """Customize check_type for handling containers.""" # Check the type in the standard way first, in order to fail quickly # in case of invalid values. root_value = super(InstructionParameter, self).check_type( value, attr, data) ...
def check_range(self, j): """Check that j is a valid index into self.""" if isinstance(j, int): if j < 0 or j >= self.size: raise QiskitIndexError("register index out of range") elif isinstance(j, slice): if j.start < 0 or j.stop >= self.size or (j...
def to_string(self, indent): """Print with indent.""" ind = indent * ' ' if self.root: print(ind, self.type, '---', self.root) else: print(ind, self.type) indent = indent + 3 ind = indent * ' ' for children in self.children: if ...
def assemble(self): """Assemble a QasmQobjInstruction""" instruction = super().assemble() if self.label: instruction.label = self.label return instruction
def is_square_matrix(mat): """Test if an array is a square matrix.""" mat = np.array(mat) if mat.ndim != 2: return False shape = mat.shape return shape[0] == shape[1]
def is_diagonal_matrix(mat, rtol=RTOL_DEFAULT, atol=ATOL_DEFAULT): """Test if an array is a diagonal matrix""" if atol is None: atol = ATOL_DEFAULT if rtol is None: rtol = RTOL_DEFAULT mat = np.array(mat) if mat.ndim != 2: return False return np.allclose(mat, np.diag(np.d...
def is_symmetric_matrix(op, rtol=RTOL_DEFAULT, atol=ATOL_DEFAULT): """Test if an array is a symmetrix matrix""" if atol is None: atol = ATOL_DEFAULT if rtol is None: rtol = RTOL_DEFAULT mat = np.array(op) if mat.ndim != 2: return False return np.allclose(mat, mat.T, rtol=...
def is_hermitian_matrix(mat, rtol=RTOL_DEFAULT, atol=ATOL_DEFAULT): """Test if an array is a Hermitian matrix""" if atol is None: atol = ATOL_DEFAULT if rtol is None: rtol = RTOL_DEFAULT mat = np.array(mat) if mat.ndim != 2: return False return np.allclose(mat, np.conj(ma...
def is_positive_semidefinite_matrix(mat, rtol=RTOL_DEFAULT, atol=ATOL_DEFAULT): """Test if a matrix is positive semidefinite""" if atol is None: atol = ATOL_DEFAULT if rtol is None: rtol = RTOL_DEFAULT if not is_hermitian_matrix(mat, rtol=rtol, atol=atol): return False # Chec...
def is_identity_matrix(mat, ignore_phase=False, rtol=RTOL_DEFAULT, atol=ATOL_DEFAULT): """Test if an array is an identity matrix.""" if atol is None: atol = ATOL_DEFAULT if rtol is None: rtol = RTOL_DEFAULT mat = np.arr...
def is_unitary_matrix(mat, rtol=RTOL_DEFAULT, atol=ATOL_DEFAULT): """Test if an array is a unitary matrix.""" if atol is None: atol = ATOL_DEFAULT if rtol is None: rtol = RTOL_DEFAULT mat = np.array(mat) # Compute A^dagger.A and see if it is identity matrix mat = np.conj(mat.T).d...
def run(self, dag): """Return a new circuit that has been optimized.""" swaps = dag.op_nodes(SwapGate) for swap in swaps: final_successor = [] for successor in dag.successors(swap): final_successor.append(successor.type == 'out' or (successor.type == 'op' ...
def left_sample(continuous_pulse: Callable, duration: int, *args, **kwargs) -> np.ndarray: """Left sample a continuous function. Args: continuous_pulse: Continuous pulse function to sample. duration: Duration to sample for. *args: Continuous pulse function args. **kwargs: Continu...
def _to_choi(rep, data, input_dim, output_dim): """Transform a QuantumChannel to the Choi representation.""" if rep == 'Choi': return data if rep == 'Operator': return _from_operator('Choi', data, input_dim, output_dim) if rep == 'SuperOp': return _superop_to_choi(data, input_dim...
def _to_superop(rep, data, input_dim, output_dim): """Transform a QuantumChannel to the SuperOp representation.""" if rep == 'SuperOp': return data if rep == 'Operator': return _from_operator('SuperOp', data, input_dim, output_dim) if rep == 'Choi': return _choi_to_superop(data, ...
def _to_kraus(rep, data, input_dim, output_dim): """Transform a QuantumChannel to the Kraus representation.""" if rep == 'Kraus': return data if rep == 'Stinespring': return _stinespring_to_kraus(data, input_dim, output_dim) if rep == 'Operator': return _from_operator('Kraus', da...
def _to_chi(rep, data, input_dim, output_dim): """Transform a QuantumChannel to the Chi representation.""" if rep == 'Chi': return data # Check valid n-qubit input _check_nqubit_dim(input_dim, output_dim) if rep == 'Operator': return _from_operator('Chi', data, input_dim, output_dim)...
def _to_ptm(rep, data, input_dim, output_dim): """Transform a QuantumChannel to the PTM representation.""" if rep == 'PTM': return data # Check valid n-qubit input _check_nqubit_dim(input_dim, output_dim) if rep == 'Operator': return _from_operator('PTM', data, input_dim, output_dim)...
def _to_stinespring(rep, data, input_dim, output_dim): """Transform a QuantumChannel to the Stinespring representation.""" if rep == 'Stinespring': return data if rep == 'Operator': return _from_operator('Stinespring', data, input_dim, output_dim) # Convert via Superoperator representati...
def _to_operator(rep, data, input_dim, output_dim): """Transform a QuantumChannel to the Operator representation.""" if rep == 'Operator': return data if rep == 'Stinespring': return _stinespring_to_operator(data, input_dim, output_dim) # Convert via Kraus representation if rep != 'K...
def _from_operator(rep, data, input_dim, output_dim): """Transform Operator representation to other representation.""" if rep == 'Operator': return data if rep == 'SuperOp': return np.kron(np.conj(data), data) if rep == 'Choi': vec = np.ravel(data, order='F') return np.ou...
def _stinespring_to_operator(data, input_dim, output_dim): """Transform Stinespring representation to Operator representation.""" trace_dim = data[0].shape[0] // output_dim if data[1] is not None or trace_dim != 1: raise QiskitError( 'Channel cannot be converted to Operator representatio...
def _superop_to_choi(data, input_dim, output_dim): """Transform SuperOp representation to Choi representation.""" shape = (output_dim, output_dim, input_dim, input_dim) return _reshuffle(data, shape)
def _choi_to_superop(data, input_dim, output_dim): """Transform Choi to SuperOp representation.""" shape = (input_dim, output_dim, input_dim, output_dim) return _reshuffle(data, shape)
def _kraus_to_choi(data, input_dim, output_dim): """Transform Kraus representation to Choi representation.""" choi = 0 kraus_l, kraus_r = data if kraus_r is None: for i in kraus_l: vec = i.ravel(order='F') choi += np.outer(vec, vec.conj()) else: for i, j in zi...
def _choi_to_kraus(data, input_dim, output_dim, atol=ATOL_DEFAULT): """Transform Choi representation to Kraus representation.""" # Check if hermitian matrix if is_hermitian_matrix(data, atol=atol): # Get eigen-decomposition of Choi-matrix w, v = la.eigh(data) # Check eigenvaleus are ...