Class: NuSVC

Nu-Support Vector Classification.

Similar to SVC but uses a parameter to control the number of support vectors.

The implementation is based on libsvm.

Read more in the User Guide.

Python Reference

Constructors

new NuSVC()

new NuSVC(opts?): NuSVC

Parameters

ParameterTypeDescription
opts?object-
opts.break_ties?booleanIf true, decision_function_shape='ovr', and number of classes > 2, predict will break ties according to the confidence values of decision_function; otherwise the first class among the tied classes is returned. Please note that breaking ties comes at a relatively high computational cost compared to a simple predict.
opts.cache_size?numberSpecify the size of the kernel cache (in MB).
opts.class_weight?anySet the parameter C of class i to class_weight[i]*C for SVC. If not given, all classes are supposed to have weight one. The “balanced” mode uses the values of y to automatically adjust weights inversely proportional to class frequencies as n_samples / (n_classes \* np.bincount(y)).
opts.coef0?numberIndependent term in kernel function. It is only significant in ‘poly’ and ‘sigmoid’.
opts.decision_function_shape?"ovr" | "ovo"Whether to return a one-vs-rest (‘ovr’) decision function of shape (n_samples, n_classes) as all other classifiers, or the original one-vs-one (‘ovo’) decision function of libsvm which has shape (n_samples, n_classes * (n_classes - 1) / 2). However, one-vs-one (‘ovo’) is always used as multi-class strategy. The parameter is ignored for binary classification.
opts.degree?numberDegree of the polynomial kernel function (‘poly’). Must be non-negative. Ignored by all other kernels.
opts.gamma?number | "auto" | "scale"Kernel coefficient for ‘rbf’, ‘poly’ and ‘sigmoid’.
opts.kernel?"sigmoid" | "precomputed" | "linear" | "poly" | "rbf"Specifies the kernel type to be used in the algorithm. If none is given, ‘rbf’ will be used. If a callable is given it is used to precompute the kernel matrix. For an intuitive visualization of different kernel types see Plot classification boundaries with different SVM Kernels.
opts.max_iter?numberHard limit on iterations within solver, or -1 for no limit.
opts.nu?numberAn upper bound on the fraction of margin errors (see User Guide) and a lower bound of the fraction of support vectors. Should be in the interval (0, 1].
opts.probability?booleanWhether to enable probability estimates. This must be enabled prior to calling fit, will slow down that method as it internally uses 5-fold cross-validation, and predict_proba may be inconsistent with predict. Read more in the User Guide.
opts.random_state?numberControls the pseudo random number generation for shuffling the data for probability estimates. Ignored when probability is false. Pass an int for reproducible output across multiple function calls. See Glossary.
opts.shrinking?booleanWhether to use the shrinking heuristic. See the User Guide.
opts.tol?numberTolerance for stopping criterion.
opts.verbose?booleanEnable verbose output. Note that this setting takes advantage of a per-process runtime setting in libsvm that, if enabled, may not work properly in a multithreaded context.

Returns NuSVC

Defined in generated/svm/NuSVC.ts:27

Properties

PropertyTypeDefault valueDefined in
_isDisposedbooleanfalsegenerated/svm/NuSVC.ts:25
_isInitializedbooleanfalsegenerated/svm/NuSVC.ts:24
_pyPythonBridgeundefinedgenerated/svm/NuSVC.ts:23
idstringundefinedgenerated/svm/NuSVC.ts:20
optsanyundefinedgenerated/svm/NuSVC.ts:21

Accessors

class_weight_

Get Signature

get class_weight_(): Promise<ArrayLike>

Multipliers of parameter C of each class. Computed based on the class_weight parameter.

Returns Promise<ArrayLike>

Defined in generated/svm/NuSVC.ts:527


classes_

Get Signature

get classes_(): Promise<ArrayLike>

The unique classes labels.

Returns Promise<ArrayLike>

Defined in generated/svm/NuSVC.ts:550


dual_coef_

Get Signature

get dual_coef_(): Promise<ArrayLike[]>

Dual coefficients of the support vector in the decision function (see Mathematical formulation), multiplied by their targets. For multiclass, coefficient for all 1-vs-1 classifiers. The layout of the coefficients in the multiclass case is somewhat non-trivial. See the multi-class section of the User Guide for details.

Returns Promise<ArrayLike[]>

Defined in generated/svm/NuSVC.ts:572


feature_names_in_

Get Signature

get feature_names_in_(): Promise<ArrayLike>

Names of features seen during fit. Defined only when X has feature names that are all strings.

Returns Promise<ArrayLike>

Defined in generated/svm/NuSVC.ts:664


fit_status_

Get Signature

get fit_status_(): Promise<number>

0 if correctly fitted, 1 if the algorithm did not converge.

Returns Promise<number>

Defined in generated/svm/NuSVC.ts:595


intercept_

Get Signature

get intercept_(): Promise<ArrayLike>

Constants in decision function.

Returns Promise<ArrayLike>

Defined in generated/svm/NuSVC.ts:618


n_features_in_

Get Signature

get n_features_in_(): Promise<number>

Number of features seen during fit.

Returns Promise<number>

Defined in generated/svm/NuSVC.ts:641


n_iter_

Get Signature

get n_iter_(): Promise<ArrayLike>

Number of iterations run by the optimization routine to fit the model. The shape of this attribute depends on the number of models optimized which in turn depends on the number of classes.

Returns Promise<ArrayLike>

Defined in generated/svm/NuSVC.ts:689


py

Get Signature

get py(): PythonBridge

Returns PythonBridge

Set Signature

set py(pythonBridge): void

Parameters

ParameterType
pythonBridgePythonBridge

Returns void

Defined in generated/svm/NuSVC.ts:133


shape_fit_

Get Signature

get shape_fit_(): Promise<any[]>

Array dimensions of training vector X.

Returns Promise<any[]>

Defined in generated/svm/NuSVC.ts:758


support_

Get Signature

get support_(): Promise<ArrayLike>

Indices of support vectors.

Returns Promise<ArrayLike>

Defined in generated/svm/NuSVC.ts:711


support_vectors_

Get Signature

get support_vectors_(): Promise<ArrayLike[]>

Support vectors.

Returns Promise<ArrayLike[]>

Defined in generated/svm/NuSVC.ts:733

Methods

decision_function()

decision_function(opts): Promise<ArrayLike[]>

Evaluate the decision function for the samples in X.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]The input samples.

Returns Promise<ArrayLike[]>

Defined in generated/svm/NuSVC.ts:201


dispose()

dispose(): Promise<void>

Disposes of the underlying Python resources.

Once dispose() is called, the instance is no longer usable.

Returns Promise<void>

Defined in generated/svm/NuSVC.ts:184


fit()

fit(opts): Promise<any>

Fit the SVM model according to the given training data.

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?ArrayLikePer-sample weights. Rescale C per sample. Higher weights force the classifier to put more emphasis on these points.
opts.X?ArrayLikeTraining 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).
opts.y?ArrayLikeTarget values (class labels in classification, real numbers in regression).

Returns Promise<any>

Defined in generated/svm/NuSVC.ts:233


get_metadata_routing()

get_metadata_routing(opts): Promise<any>

Get metadata routing of this object.

Please check User Guide on how the routing mechanism works.

Parameters

ParameterTypeDescription
optsobject-
opts.routing?anyA MetadataRequest encapsulating routing information.

Returns Promise<any>

Defined in generated/svm/NuSVC.ts:277


init()

init(py): Promise<void>

Initializes the underlying Python resources.

This instance is not usable until the Promise returned by init() resolves.

Parameters

ParameterType
pyPythonBridge

Returns Promise<void>

Defined in generated/svm/NuSVC.ts:146


predict()

predict(opts): Promise<ArrayLike>

Perform classification on samples in X.

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

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLikeFor kernel=”precomputed”, the expected shape of X is (n_samples_test, n_samples_train).

Returns Promise<ArrayLike>

Defined in generated/svm/NuSVC.ts:311


predict_log_proba()

predict_log_proba(opts): Promise<ArrayLike[]>

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.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]For kernel=”precomputed”, the expected shape of X is (n_samples_test, n_samples_train).

Returns Promise<ArrayLike[]>

Defined in generated/svm/NuSVC.ts:345


predict_proba()

predict_proba(opts): Promise<ArrayLike[]>

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.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]For kernel=”precomputed”, the expected shape of X is (n_samples_test, n_samples_train).

Returns Promise<ArrayLike[]>

Defined in generated/svm/NuSVC.ts:379


score()

score(opts): Promise<number>

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.

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?ArrayLikeSample weights.
opts.X?ArrayLike[]Test samples.
opts.y?ArrayLikeTrue labels for X.

Returns Promise<number>

Defined in generated/svm/NuSVC.ts:413


set_fit_request()

set_fit_request(opts): Promise<any>

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:

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?string | booleanMetadata routing for sample_weight parameter in fit.

Returns Promise<any>

Defined in generated/svm/NuSVC.ts:459


set_score_request()

set_score_request(opts): Promise<any>

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:

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?string | booleanMetadata routing for sample_weight parameter in score.

Returns Promise<any>

Defined in generated/svm/NuSVC.ts:495