QSVC

class QSVC(*, quantum_kernel=None, **kwargs)

ベースクラス: SVC, SerializableModelMixin

Quantum Support Vector Classifier that extends the scikit-learn sklearn.svm.SVC classifier and introduces an additional quantum_kernel parameter.

This class shows how to use a quantum kernel for classification. The class inherits its methods like fit and predict from scikit-learn, see the example below. Read more in the scikit-learn user guide.

Example

qsvc = QSVC(quantum_kernel=qkernel)
qsvc.fit(sample_train,label_train)
qsvc.predict(sample_test)

パラメータ:

• quantum_kernel (BaseKernel | None) – A quantum kernel to be used for classification. Has to be None when a precomputed kernel is used. If None, default to FidelityQuantumKernel.

• *args – Variable length argument list to pass to SVC constructor.

• **kwargs – Arbitrary keyword arguments to pass to SVC constructor.

Attributes

coef_

Weights assigned to the features when kernel=」linear」.

戻り値の型:

ndarray of shape (n_features, n_classes)

n_support_

Number of support vectors for each class.

probA_

Parameter learned in Platt scaling when probability=True.

戻り値の型:

ndarray of shape (n_classes * (n_classes - 1) / 2)

probB_

Parameter learned in Platt scaling when probability=True.

戻り値の型:

ndarray of shape (n_classes * (n_classes - 1) / 2)

quantum_kernel

Returns quantum kernel

unused_param = 'nu'

Methods

decision_function(X)

Evaluate the decision function for the samples in X.

パラメータ:

X (array-like of shape (n_samples, n_features)) – The input samples.

戻り値:

X – Returns the decision function of the sample for each class in the model. If decision_function_shape=』ovr』, the shape is (n_samples, n_classes).

戻り値の型:

ndarray of shape (n_samples, n_classes * (n_classes-1) / 2)

メモ

If decision_function_shape=』ovo』, the function values are proportional to the distance of the samples X to the separating hyperplane. If the exact distances are required, divide the function values by the norm of the weight vector (coef_). See also this question for further details. If decision_function_shape=』ovr』, the decision function is a monotonic transformation of ovo decision function.

fit(X, y, sample_weight=None)

Fit the SVM model according to the given training data.

パラメータ:

• X ({array-like, sparse matrix} of shape (n_samples, n_features) or (n_samples, n_samples)) – Training vectors, where n_samples is the number of samples and n_features is the number of features. For kernel=」precomputed」, the expected shape of X is (n_samples, n_samples).

• y (array-like of shape (n_samples,)) – Target values (class labels in classification, real numbers in regression).

• sample_weight (array-like of shape (n_samples,), default=None) – Per-sample weights. Rescale C per sample. Higher weights force the classifier to put more emphasis on these points.

戻り値:

self – Fitted estimator.

戻り値の型:

object

メモ

If X and y are not C-ordered and contiguous arrays of np.float64 and X is not a scipy.sparse.csr_matrix, X and/or y may be copied.

If X is a dense array, then the other methods will not support sparse matrices as input.

get_metadata_routing()

Get metadata routing of this object.

Please check User Guide on how the routing mechanism works.

戻り値:

routing – A MetadataRequest encapsulating routing information.

戻り値の型:

MetadataRequest

get_params(deep=True)

Get parameters for this estimator.

パラメータ:

deep (bool, default=True) – If True, will return the parameters for this estimator and contained subobjects that are estimators.

戻り値:

params – Parameter names mapped to their values.

戻り値の型:

dict

classmethod load(file_name)

Loads a model from the file. If the loaded model is not an instance of the class whose method was called, then a warning is raised. Nevertheless, the loaded model may be a valid model.

パラメータ:

file_name (str) – a file name or path to load a model from.

戻り値:

A loaded model.

例外:

TypeError – if a loaded model is not an instance of the expected class.

戻り値の型:

Any

predict(X)

Perform classification on samples in X.

For an one-class model, +1 or -1 is returned.

パラメータ:

X ({array-like, sparse matrix} of shape (n_samples, n_features) or (n_samples_test, n_samples_train)) – For kernel=」precomputed」, the expected shape of X is (n_samples_test, n_samples_train).

戻り値:

y_pred – Class labels for samples in X.

戻り値の型:

ndarray of shape (n_samples,)

predict_log_proba(X)

Compute log probabilities of possible outcomes for samples in X.

The model need to have probability information computed at training time: fit with attribute probability set to True.

パラメータ:

X (array-like of shape (n_samples, n_features) or (n_samples_test, n_samples_train)) – For kernel=」precomputed」, the expected shape of X is (n_samples_test, n_samples_train).

戻り値:

T – Returns the log-probabilities of the sample for each class in the model. The columns correspond to the classes in sorted order, as they appear in the attribute classes_.

戻り値の型:

ndarray of shape (n_samples, n_classes)

メモ

The probability model is created using cross validation, so the results can be slightly different than those obtained by predict. Also, it will produce meaningless results on very small datasets.

predict_proba(X)

Compute probabilities of possible outcomes for samples in X.

The model needs to have probability information computed at training time: fit with attribute probability set to True.

パラメータ:

X (array-like of shape (n_samples, n_features)) – For kernel=」precomputed」, the expected shape of X is (n_samples_test, n_samples_train).

戻り値:

T – Returns the probability of the sample for each class in the model. The columns correspond to the classes in sorted order, as they appear in the attribute classes_.

戻り値の型:

ndarray of shape (n_samples, n_classes)

メモ

The probability model is created using cross validation, so the results can be slightly different than those obtained by predict. Also, it will produce meaningless results on very small datasets.

save(file_name)

Saves this model to the specified file. Internally, the model is serialized via dill. All parameters are saved, including a primitive instance that is referenced by internal objects. That means if a model is loaded from a file and is used, for instance, for inference, the same primitive will be used even if a cloud primitive was used.

パラメータ:

file_name (str) – a file name or path where to save the model.

score(X, y, sample_weight=None)

Return the mean accuracy on the given test data and labels.

In multi-label classification, this is the subset accuracy which is a harsh metric since you require for each sample that each label set be correctly predicted.

パラメータ:

• X (array-like of shape (n_samples, n_features)) – Test samples.

• y (array-like of shape (n_samples,) or (n_samples, n_outputs)) – True labels for X.

• sample_weight (array-like of shape (n_samples,), default=None) – Sample weights.

戻り値:

score – Mean accuracy of self.predict(X) w.r.t. y.

戻り値の型:

float

set_fit_request(*, sample_weight='$UNCHANGED$')

Request metadata passed to the fit method.

Note that this method is only relevant if enable_metadata_routing=True (see sklearn.set_config()). Please see User Guide on how the routing mechanism works.

The options for each parameter are:

• True: metadata is requested, and passed to fit if provided. The request is ignored if metadata is not provided.

• False: metadata is not requested and the meta-estimator will not pass it to fit.

• None: metadata is not requested, and the meta-estimator will raise an error if the user provides it.

• str: metadata should be passed to the meta-estimator with this given alias instead of the original name.

The default (sklearn.utils.metadata_routing.UNCHANGED) retains the existing request. This allows you to change the request for some parameters and not others.

バージョン 1.3 で追加.

注釈

This method is only relevant if this estimator is used as a sub-estimator of a meta-estimator, e.g. used inside a Pipeline. Otherwise it has no effect.

パラメータ:

sample_weight (str, True, False, or None, default=sklearn.utils.metadata_routing.UNCHANGED) – Metadata routing for sample_weight parameter in fit.

戻り値:

self – The updated object.

戻り値の型:

object

set_params(**params)

Set the parameters of this estimator.

The method works on simple estimators as well as on nested objects (such as Pipeline). The latter have parameters of the form <component>__<parameter> so that it’s possible to update each component of a nested object.

パラメータ:

**params (dict) – Estimator parameters.

戻り値:

self – Estimator instance.

戻り値の型:

estimator instance

set_score_request(*, sample_weight='$UNCHANGED$')

Request metadata passed to the score method.

Note that this method is only relevant if enable_metadata_routing=True (see sklearn.set_config()). Please see User Guide on how the routing mechanism works.

The options for each parameter are:

• True: metadata is requested, and passed to score if provided. The request is ignored if metadata is not provided.

• False: metadata is not requested and the meta-estimator will not pass it to score.

• None: metadata is not requested, and the meta-estimator will raise an error if the user provides it.

• str: metadata should be passed to the meta-estimator with this given alias instead of the original name.

The default (sklearn.utils.metadata_routing.UNCHANGED) retains the existing request. This allows you to change the request for some parameters and not others.

バージョン 1.3 で追加.

注釈

This method is only relevant if this estimator is used as a sub-estimator of a meta-estimator, e.g. used inside a Pipeline. Otherwise it has no effect.

パラメータ:

sample_weight (str, True, False, or None, default=sklearn.utils.metadata_routing.UNCHANGED) – Metadata routing for sample_weight parameter in score.

戻り値:

self – The updated object.

戻り値の型:

object