NuSVR
Nu Support Vector Regression.
Similar to NuSVC, for regression, uses a parameter nu to control the number of support vectors. However, unlike NuSVC, where nu replaces C, here nu replaces the parameter epsilon of epsilon-SVR.
The implementation is based on libsvm.
Read more in the User Guide.
Python Reference (opens in a new tab)
Constructors
constructor()
Signature
new NuSVR(opts?: object): NuSVR;
Parameters
Name | Type | Description |
---|---|---|
opts? | object | - |
opts.C? | number | Penalty parameter C of the error term. Default Value 1 |
opts.cache_size? | number | Specify the size of the kernel cache (in MB). Default Value 200 |
opts.coef0? | number | Independent term in kernel function. It is only significant in ‘poly’ and ‘sigmoid’. Default Value 0 |
opts.degree? | number | Degree of the polynomial kernel function (‘poly’). Must be non-negative. Ignored by all other kernels. Default Value 3 |
opts.gamma? | number | "auto" | "scale" | Kernel coefficient for ‘rbf’, ‘poly’ and ‘sigmoid’. Default Value 'scale' |
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. Default Value 'rbf' |
opts.max_iter? | number | Hard limit on iterations within solver, or -1 for no limit. Default Value -1 |
opts.nu? | number | An upper bound on the fraction of training errors and a lower bound of the fraction of support vectors. Should be in the interval (0, 1]. By default 0.5 will be taken. Default Value 0.5 |
opts.shrinking? | boolean | Whether to use the shrinking heuristic. See the User Guide. Default Value true |
opts.tol? | number | Tolerance for stopping criterion. Default Value 0.001 |
opts.verbose? | boolean | Enable 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. Default Value false |
Returns
Defined in: generated/svm/NuSVR.ts:27 (opens in a new tab)
Properties
_isDisposed
boolean
=false
Defined in: generated/svm/NuSVR.ts:25 (opens in a new tab)
_isInitialized
boolean
=false
Defined in: generated/svm/NuSVR.ts:24 (opens in a new tab)
_py
PythonBridge
Defined in: generated/svm/NuSVR.ts:23 (opens in a new tab)
id
string
Defined in: generated/svm/NuSVR.ts:20 (opens in a new tab)
opts
any
Defined in: generated/svm/NuSVR.ts:21 (opens in a new tab)
Accessors
class_weight_
Multipliers of parameter C for each class. Computed based on the class\_weight
parameter.
Signature
class_weight_(): Promise<ArrayLike>;
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/NuSVR.ts:319 (opens in a new tab)
dual_coef_
Coefficients of the support vector in the decision function.
Signature
dual_coef_(): Promise<ArrayLike[]>;
Returns
Promise
<ArrayLike
[]>
Defined in: generated/svm/NuSVR.ts:342 (opens in a new tab)
feature_names_in_
Names of features seen during fit. Defined only when X
has feature names that are all strings.
Signature
feature_names_in_(): Promise<ArrayLike>;
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/NuSVR.ts:434 (opens in a new tab)
fit_status_
0 if correctly fitted, 1 otherwise (will raise warning)
Signature
fit_status_(): Promise<number>;
Returns
Promise
<number
>
Defined in: generated/svm/NuSVR.ts:365 (opens in a new tab)
intercept_
Constants in decision function.
Signature
intercept_(): Promise<ArrayLike>;
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/NuSVR.ts:388 (opens in a new tab)
n_features_in_
Number of features seen during fit.
Signature
n_features_in_(): Promise<number>;
Returns
Promise
<number
>
Defined in: generated/svm/NuSVR.ts:411 (opens in a new tab)
n_iter_
Number of iterations run by the optimization routine to fit the model.
Signature
n_iter_(): Promise<number>;
Returns
Promise
<number
>
Defined in: generated/svm/NuSVR.ts:459 (opens in a new tab)
py
Signature
py(): PythonBridge;
Returns
PythonBridge
Defined in: generated/svm/NuSVR.ts:109 (opens in a new tab)
Signature
py(pythonBridge: PythonBridge): void;
Parameters
Name | Type |
---|---|
pythonBridge | PythonBridge |
Returns
void
Defined in: generated/svm/NuSVR.ts:113 (opens in a new tab)
shape_fit_
Array dimensions of training vector X
.
Signature
shape_fit_(): Promise<any[]>;
Returns
Promise
<any
[]>
Defined in: generated/svm/NuSVR.ts:481 (opens in a new tab)
support_
Indices of support vectors.
Signature
support_(): Promise<ArrayLike>;
Returns
Promise
<ArrayLike
>
Defined in: generated/svm/NuSVR.ts:504 (opens in a new tab)
support_vectors_
Support vectors.
Signature
support_vectors_(): Promise<ArrayLike[]>;
Returns
Promise
<ArrayLike
[]>
Defined in: generated/svm/NuSVR.ts:526 (opens in a new tab)
Methods
dispose()
Disposes of the underlying Python resources.
Once dispose()
is called, the instance is no longer usable.
Signature
dispose(): Promise<void>;
Returns
Promise
<void
>
Defined in: generated/svm/NuSVR.ts:171 (opens in a new tab)
fit()
Fit the SVM model according to the given training data.
Signature
fit(opts: object): Promise<any>;
Parameters
Name | Type | Description |
---|---|---|
opts | object | - |
opts.X? | ArrayLike | 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). |
opts.sample_weight? | ArrayLike | Per-sample weights. Rescale C per sample. Higher weights force the classifier to put more emphasis on these points. |
opts.y? | ArrayLike | Target values (class labels in classification, real numbers in regression). |
Returns
Promise
<any
>
Defined in: generated/svm/NuSVR.ts:188 (opens in a new tab)
init()
Initializes the underlying Python resources.
This instance is not usable until the Promise
returned by init()
resolves.
Signature
init(py: PythonBridge): Promise<void>;
Parameters
Name | Type |
---|---|
py | PythonBridge |
Returns
Promise
<void
>
Defined in: generated/svm/NuSVR.ts:122 (opens in a new tab)
predict()
Perform regression on samples in X.
For an one-class model, +1 (inlier) or -1 (outlier) is returned.
Signature
predict(opts: object): Promise<ArrayLike>;
Parameters
Name | Type | Description |
---|---|---|
opts | object | - |
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/NuSVR.ts:237 (opens in a new tab)
score()
Return the coefficient of determination of the prediction.
The coefficient of determination \(R^2\) is defined as \((1 - \frac{u}{v})\), where \(u\) is the residual sum of squares ((y\_true \- y\_pred)\*\* 2).sum()
and \(v\) is the total sum of squares ((y\_true \- y\_true.mean()) \*\* 2).sum()
. The best possible score is 1.0 and it can be negative (because the model can be arbitrarily worse). A constant model that always predicts the expected value of y
, disregarding the input features, would get a \(R^2\) score of 0.0.
Signature
score(opts: object): Promise<number>;
Parameters
Name | Type | Description |
---|---|---|
opts | object | - |
opts.X? | ArrayLike [] | Test samples. For some estimators this may be a precomputed kernel matrix or a list of generic objects instead with shape (n\_samples, n\_samples\_fitted) , where n\_samples\_fitted is the number of samples used in the fitting for the estimator. |
opts.sample_weight? | ArrayLike | Sample weights. |
opts.y? | ArrayLike | True values for X . |
Returns
Promise
<number
>
Defined in: generated/svm/NuSVR.ts:272 (opens in a new tab)