Merge branch 'master' into statefn-eval

.pylintdict

@@ -703,6 +703,7 @@ wigner
 wikipedia
 workq
 wrt
+wvf
 xatol
 xixj
 xopt

README.md

@@ -70,13 +70,19 @@ these on a quantum backend, whether a real device or simulator.
 
 ### Optional Installs
 
+_**Note:** while the packages below can be installed directly by pip install, e.g. `pip install cplex`
+by doing so via the Aqua extra_requires, in this case `pip install qiskit-aqua[cplex]` will ensure
+that a version compatible with Qiskit is installed._
+
 * **IBM CPLEX** may be [installed](https://qiskit.org/documentation/apidoc/qiskit.aqua.algorithms.minimum_eigen_solvers.cplex.html)
-  to allow the use of the `ClassicalCPLEX` classical solver algorithm. `pip install cplex` may be used
-  as an alternative.
-* **PyTorch**, may be installed either using command `pip install torch` to install the
+  to allow the use of the `ClassicalCPLEX` classical solver algorithm. 
+  `pip install qiskit-aqua[cplex]` may be used to install the community version.
+* **PyTorch**, may be installed either using command `pip install qiskit-aqua[torch]` to install the
   package or refer to PyTorch [getting started](https://pytorch.org/get-started/locally/). PyTorch
   being installed will enable the neural networks `PyTorchDiscriminator` component to be used with
   the QGAN algorithm.
+* **CVXPY**, may be installed using command `pip install qiskit-aqua[cvpxy]` to enable use of the
+  `QSVM` and the classical `SklearnSVM` algorithms. 
 
 
 ### Creating Your First Quantum Program in Qiskit Aqua
@@ -399,8 +405,8 @@ validation, and benchmarking.
 
 ### Optional Installs
 
-* **IBM CPLEX** may be installed using `pip install cplex` to allow the use of the `CplexOptimzer`
-  classical solver algorithm, as well as enabling the reading of `LP` files.
+* **IBM CPLEX** may be installed using `pip install qiskit-aqua[cplex]` to allow the use of the
+ `CplexOptimzer` classical solver algorithm, as well as enabling the reading of `LP` files.
 
 ### Creating Your First Optimization Programming Experiment in Qiskit
 
@@ -485,7 +491,7 @@ This project adheres to Qiskit's [code of conduct](./CODE_OF_CONDUCT.md).
 By participating, you are expected to uphold this code.
 
 We use [GitHub issues](https://github.com/Qiskit/qiskit-aqua/issues) for tracking requests and bugs. Please
-[join the Qiskit Slack community](https://join.slack.com/t/qiskit/shared_invite/enQtODQ2NTIyOTgwMTQ3LTI0NzM2NzkzZjJhNDgzZjY5MTQzNDY3MGNiZGQzNTNkZTE4Nzg1MjMwMmFjY2UwZTgyNDlmYWQwYmZjMjE1ZTM)
+[join the Qiskit Slack community](https://ibm.co/joinqiskitslack)
 and use the [Aqua Slack channel](https://qiskit.slack.com/messages/aqua) for discussion and simple questions.
 For questions that are more suited for a forum, we use the **Qiskit** tag in [Stack Overflow](https://stackoverflow.com/questions/tagged/qiskit).
 

qiskit/aqua/algorithms/amplitude_estimators/mlae.py

@@ -189,8 +189,8 @@ def _get_hits(self) -> Tuple[List[float], List[int]]:
                 for c in self._ret['counts']:
                     one_hits += [c.get('1', 0)]  # return 0 if no key '1' found
                     all_hits += [sum(c.values())]
-        except KeyError:
-            raise AquaError('Call run() first!')
+        except KeyError as ex:
+            raise AquaError('Call run() first!') from ex
 
         return one_hits, all_hits
 
@@ -227,8 +227,8 @@ def _compute_fisher_information(self, a: Optional[float] = None,
         if a is None:
             try:
                 a = self._ret['value']
-            except KeyError:
-                raise KeyError('Call run() first!')
+            except KeyError as ex:
+                raise KeyError('Call run() first!') from ex
 
         # Corresponding angle to the value a (only use real part of 'a')
         theta_a = np.arcsin(np.sqrt(np.real(a)))
@@ -279,8 +279,8 @@ def _fisher_confint(self, alpha: float = 0.05, observed: bool = False) -> List[f
         fisher_information = None
         try:
             fisher_information = self._ret['fisher_information']
-        except KeyError:
-            raise AssertionError("Call run() first!")
+        except KeyError as ex:
+            raise AssertionError("Call run() first!") from ex
 
         if observed:
             fisher_information = self._compute_fisher_information(observed=True)

qiskit/aqua/algorithms/minimum_eigen_solvers/vqe.py

@@ -252,10 +252,10 @@ def _check_operator_varform(self):
                 try:
                     self.var_form.num_qubits = self.operator.num_qubits
                     self._var_form_params = sorted(self.var_form.parameters, key=lambda p: p.name)
-                except AttributeError:
+                except AttributeError as ex:
                     raise AquaError("The number of qubits of the variational form does not match "
                                     "the operator, and the variational form does not allow setting "
-                                    "the number of qubits using `num_qubits`.")
+                                    "the number of qubits using `num_qubits`.") from ex
 
     @VQAlgorithm.optimizer.setter  # type: ignore
     def optimizer(self, optimizer: Optimizer):

qiskit/aqua/circuits/phase_estimation_circuit.py

@@ -214,9 +214,9 @@ def construct_circuit(
             if self._iqft.num_qubits != len(a):  # check if QFT has the right size
                 try:  # try resizing
                     self._iqft.num_qubits = len(a)
-                except AttributeError:
+                except AttributeError as ex:
                     raise ValueError('The IQFT cannot be resized and does not have the '
-                                     'required size of {}'.format(len(a)))
+                                     'required size of {}'.format(len(a))) from ex
 
             if hasattr(self._iqft, 'do_swaps'):
                 self._iqft.do_swaps = False

qiskit/aqua/components/eigs/eigs_qpe.py

@@ -154,9 +154,9 @@ def apply_ne_qft(ne_qft):
                 if ne_qft.num_qubits != len(qs):
                     try:  # try resizing
                         ne_qft.num_qubits = len(qs)
-                    except AttributeError:
+                    except AttributeError as ex:
                         raise ValueError('The IQFT cannot be resized and does not have the '
-                                         'required size of {}'.format(len(qs)))
+                                         'required size of {}'.format(len(qs))) from ex
 
                 if hasattr(ne_qft, 'do_swaps'):
                     ne_qft.do_swaps = False

qiskit/aqua/components/neural_networks/_pytorch_discriminator_net.py

@@ -54,7 +54,7 @@ def __init__(self, n_features: int = 1, n_out: int = 1) -> None:
             n_out: n out
         """
 
-        super(DiscriminatorNet, self).__init__()
+        super().__init__()
         self.n_features = n_features
 
         self.hidden0 = nn.Sequential(

qiskit/aqua/components/oracles/logical_expression_oracle.py

@@ -137,8 +137,9 @@ def __init__(self,
             try:
                 expression = LogicalExpressionOracle._dimacs_cnf_to_expression(expression)
                 raw_expr = parse_expr(expression)
-            except Exception:
-                raise AquaError('Failed to parse the input expression: {}.'.format(orig_expression))
+            except Exception as ex:
+                raise AquaError(
+                    'Failed to parse the input expression: {}.'.format(orig_expression)) from ex
         self._expr = raw_expr
         self._process_expr()
         self.construct_circuit()

qiskit/aqua/operators/list_ops/list_op.py

@@ -129,7 +129,10 @@ def primitive_strings(self) -> Set[str]:
 
     @property
     def num_qubits(self) -> int:
-        return self.oplist[0].num_qubits
+        num_qubits0 = self.oplist[0].num_qubits
+        if not all(num_qubits0 == op.num_qubits for op in self.oplist):
+            raise ValueError('Operators in ListOp have differing numbers of qubits.')
+        return num_qubits0
 
     def add(self, other: OperatorBase) -> OperatorBase:
         if self == other:

qiskit/aqua/operators/list_ops/summed_op.py

@@ -153,9 +153,9 @@ def to_legacy_op(self, massive: bool = False) -> LegacyBaseOperator:
         if isinstance(self.coeff, ParameterExpression):
             try:
                 coeff = float(self.coeff)
-            except TypeError:
+            except TypeError as ex:
                 raise TypeError('Cannot convert Operator with unbound parameter {} to Legacy '
-                                'Operator'.format(self.coeff))
+                                'Operator'.format(self.coeff)) from ex
         else:
             coeff = cast(float, self.coeff)
 

qiskit/aqua/operators/operator_base.py

@@ -488,8 +488,8 @@ def _unroll_param_dict(value_dict: Dict[Union[ParameterExpression, ParameterVect
                         OperatorBase._get_param_dict_for_index(unrolled_value_dict,  # type: ignore
                                                                i))
                 return unrolled_value_dict_list
-            except IndexError:
-                raise AquaError('Parameter binding lists must all be the same length.')
+            except IndexError as ex:
+                raise AquaError('Parameter binding lists must all be the same length.') from ex
         return unrolled_value_dict  # type: ignore
 
     @staticmethod

qiskit/aqua/operators/primitive_ops/circuit_op.py

@@ -132,7 +132,7 @@ def compose(self, other: OperatorBase) -> OperatorBase:
             else:
                 return CircuitOp(new_qc, coeff=self.coeff * other.coeff)
 
-        return super(CircuitOp, self).compose(other)
+        return super().compose(other)
 
     def to_matrix(self, massive: bool = False) -> np.ndarray:
         if self.num_qubits > 16 and not massive:

qiskit/aqua/operators/primitive_ops/matrix_op.py

@@ -121,7 +121,7 @@ def compose(self, other: OperatorBase) -> OperatorBase:
             return MatrixOp(self.primitive.compose(other.primitive, front=True),  # type: ignore
                             coeff=self.coeff * other.coeff)
 
-        return super(MatrixOp, self).compose(other)
+        return super().compose(other)
 
     def to_matrix(self, massive: bool = False) -> np.ndarray:
         return self.primitive.data * self.coeff  # type: ignore

qiskit/aqua/operators/primitive_ops/pauli_op.py

@@ -115,7 +115,7 @@ def compose(self, other: OperatorBase) -> OperatorBase:
         if isinstance(other, (CircuitOp, CircuitStateFn)):
             return self.to_circuit_op().compose(other)
 
-        return super(PauliOp, self).compose(other)
+        return super().compose(other)
 
     def to_matrix(self, massive: bool = False) -> np.ndarray:
         if self.num_qubits > 16 and not massive:
@@ -283,9 +283,9 @@ def to_legacy_op(self, massive: bool = False) -> WeightedPauliOperator:
         if isinstance(self.coeff, ParameterExpression):
             try:
                 coeff = float(self.coeff)
-            except TypeError:
+            except TypeError as ex:
                 raise TypeError('Cannot convert Operator with unbound parameter {} to Legacy '
-                                'Operator'.format(self.coeff))
+                                'Operator'.format(self.coeff)) from ex
         else:
             coeff = cast(float, self.coeff)
         return WeightedPauliOperator(paulis=[(coeff, self.primitive)])  # type: ignore

qiskit/aqua/utils/dataset_helper.py

@@ -97,7 +97,7 @@ def split_dataset_to_data_and_labels(dataset, class_names=None):
                 labels.append(class_to_label[class_name])
             except Exception as ex:  # pylint: disable=broad-except
                 raise KeyError('The dataset has different class names to '
-                               'the training data. error message: {}'.format(ex))
+                               'the training data. error message: {}'.format(ex)) from ex
     data = np.asarray(data)
     labels = np.asarray(labels)
     if class_names is None:

qiskit/chemistry/drivers/fcidumpd/parser.py

@@ -38,8 +38,8 @@ def parse(fcidump: str) -> Dict[str, Any]:
     try:
         with open(fcidump, 'r') as file:
             fcidump_str = file.read()
-    except OSError:
-        raise QiskitChemistryError("Input file '{}' cannot be read!".format(fcidump))
+    except OSError as ex:
+        raise QiskitChemistryError("Input file '{}' cannot be read!".format(fcidump)) from ex
 
     output = {}  # type: Dict[str, Any]
 
@@ -139,18 +139,18 @@ def parse(fcidump: str) -> Dict[str, Any]:
             try:
                 hij_elements.remove((i-1, a-1))
                 hij[i-1][a-1] = x
-            except KeyError:
+            except KeyError as ex:
                 if _uhf:
                     hij_b_elements.remove((i-1, a-1))
                     hij_b[i-1-norb][a-1-norb] = x
                 else:
                     raise QiskitChemistryError("Unkown 1-electron integral indices encountered in \
-                            '{}'".format((i, a)))
+                            '{}'".format((i, a))) from ex
         else:
             try:
                 hijkl_elements.remove((i-1, a-1, j-1, b-1))
                 hijkl[i-1][a-1][j-1][b-1] = x
-            except KeyError:
+            except KeyError as ex:
                 if _uhf:
                     try:
                         hijkl_ab_elements.remove((i-1, a-1, j-1, b-1))
@@ -164,7 +164,7 @@ def parse(fcidump: str) -> Dict[str, Any]:
                             hijkl_bb[i-1-norb][a-1-norb][j-1-norb][b-1-norb] = x
                 else:
                     raise QiskitChemistryError("Unkown 2-electron integral indices encountered in \
-                            '{}'".format((i, a, j, b)))
+                            '{}'".format((i, a, j, b))) from ex
 
     # iterate over still empty elements in 1-electron matrix and populate with symmetric ones
     # if any elements are not populated these will be zero

qiskit/chemistry/drivers/gaussiand/gaussiandriver.py

@@ -188,7 +188,7 @@ def _parse_matrix_file(self, fname, useao2e=False):
                 if mnfe.name == 'qcmatrixio' else str(mnfe)
 
             logger.info(msg)
-            raise QiskitChemistryError(msg)
+            raise QiskitChemistryError(msg) from mnfe
 
         mel = MatEl(file=fname)
         logger.debug('MatrixElement file:\n%s', mel)
@@ -344,11 +344,11 @@ def _run_g16(cfg):
             process = Popen(GAUSSIAN_16, stdin=PIPE, stdout=PIPE, universal_newlines=True)
             stdout, _ = process.communicate(cfg)
             process.wait()
-        except Exception:
+        except Exception as ex:
             if process is not None:
                 process.kill()
 
-            raise QiskitChemistryError('{} run has failed'.format(GAUSSIAN_16_DESC))
+            raise QiskitChemistryError('{} run has failed'.format(GAUSSIAN_16_DESC)) from ex
 
         if process.returncode != 0:
             errmsg = ""

qiskit/chemistry/drivers/psi4d/psi4driver.py

@@ -131,11 +131,11 @@ def _run_psi4(input_file, output_file):
                                        stdout=subprocess.PIPE, universal_newlines=True)
             stdout, _ = process.communicate()
             process.wait()
-        except Exception:
+        except Exception as ex:
             if process is not None:
                 process.kill()
 
-            raise QiskitChemistryError('{} run has failed'.format(PSI4))
+            raise QiskitChemistryError('{} run has failed'.format(PSI4)) from ex
 
         if process.returncode != 0:
             errmsg = ""

qiskit/chemistry/qmolecule.py

@@ -536,7 +536,7 @@ def twoe_to_spin(mohijkl, mohijkl_bb=None, mohijkl_ba=None, threshold=1E-12):
         return moh2_qubit
 
     symbols = [
-        # pylint: disable=bad-whitespace
+        # pylint: disable=bad-option-value,bad-whitespace
         '_',
         'H',  'He',
         'Li', 'Be', 'B',  'C',  'N',  'O',  'F',  'Ne',

qiskit/finance/data_providers/_base_data_provider.py

@@ -75,10 +75,10 @@ def get_mean_vector(self) -> np.ndarray:
                 raise QiskitFinanceError(
                     'No data loaded, yet. Please run the method run() first to load the data.'
                 )
-        except AttributeError:
+        except AttributeError as ex:
             raise QiskitFinanceError(
                 'No data loaded, yet. Please run the method run() first to load the data.'
-            )
+            ) from ex
         self.mean = np.mean(self._data, axis=1)
         return self.mean
 
@@ -106,10 +106,10 @@ def get_period_return_mean_vector(self) -> np.ndarray:
                 raise QiskitFinanceError(
                     'No data loaded, yet. Please run the method run() first to load the data.'
                 )
-        except AttributeError:
+        except AttributeError as ex:
             raise QiskitFinanceError(
                 'No data loaded, yet. Please run the method run() first to load the data.'
-            )
+            ) from ex
         _div_func = np.vectorize(BaseDataProvider._divide)
         period_returns = _div_func(np.array(self._data)[:, 1:], np.array(self._data)[:, :-1]) - 1
         self.period_return_mean = np.mean(period_returns, axis=1)
@@ -130,10 +130,10 @@ def get_covariance_matrix(self) -> np.ndarray:
                 raise QiskitFinanceError(
                     'No data loaded, yet. Please run the method run() first to load the data.'
                 )
-        except AttributeError:
+        except AttributeError as ex:
             raise QiskitFinanceError(
                 'No data loaded, yet. Please run the method run() first to load the data.'
-            )
+            ) from ex
         self.cov = np.cov(self._data, rowvar=True)
         return self.cov
 
@@ -152,10 +152,10 @@ def get_period_return_covariance_matrix(self) -> np.ndarray:
                 raise QiskitFinanceError(
                     'No data loaded, yet. Please run the method run() first to load the data.'
                 )
-        except AttributeError:
+        except AttributeError as ex:
             raise QiskitFinanceError(
                 'No data loaded, yet. Please run the method run() first to load the data.'
-            )
+            ) from ex
         _div_func = np.vectorize(BaseDataProvider._divide)
         period_returns = _div_func(np.array(self._data)[:, 1:], np.array(self._data)[:, :-1]) - 1
         self.period_return_cov = np.cov(period_returns)
@@ -176,10 +176,10 @@ def get_similarity_matrix(self) -> np.ndarray:
                 raise QiskitFinanceError(
                     'No data loaded, yet. Please run the method run() first to load the data.'
                 )
-        except AttributeError:
+        except AttributeError as ex:
             raise QiskitFinanceError(
                 'No data loaded, yet. Please run the method run() first to load the data.'
-            )
+            ) from ex
         self.rho = np.zeros((self._n, self._n))
         for i_i in range(0, self._n):
             self.rho[i_i, i_i] = 1.