Trait opencv::ml::SVM[−][src]

pub trait SVM: SVMConst + StatModel {

Show 14 methods    fn as_raw_mut_SVM(&mut self) -> *mut c_void;

    fn set_type(&mut self, val: i32) -> Result<()> { ... }

    fn set_gamma(&mut self, val: f64) -> Result<()> { ... }

    fn set_coef0(&mut self, val: f64) -> Result<()> { ... }

    fn set_degree(&mut self, val: f64) -> Result<()> { ... }

    fn set_c(&mut self, val: f64) -> Result<()> { ... }

    fn set_nu(&mut self, val: f64) -> Result<()> { ... }

    fn set_p(&mut self, val: f64) -> Result<()> { ... }

    fn set_class_weights(&mut self, val: &Mat) -> Result<()> { ... }

    fn set_term_criteria(&mut self, val: TermCriteria) -> Result<()> { ... }

    fn set_kernel(&mut self, kernel_type: i32) -> Result<()> { ... }

    fn set_custom_kernel(&mut self, _kernel: &Ptr<dyn SVM_Kernel>) -> Result<()> { ... }

    fn train_auto(
        &mut self, 
        data: &Ptr<dyn TrainData>, 
        k_fold: i32, 
        cgrid: ParamGrid, 
        gamma_grid: ParamGrid, 
        p_grid: ParamGrid, 
        nu_grid: ParamGrid, 
        coeff_grid: ParamGrid, 
        degree_grid: ParamGrid, 
        balanced: bool
    ) -> Result<bool> { ... }

    fn train_auto_with_data(
        &mut self, 
        samples: &dyn ToInputArray, 
        layout: i32, 
        responses: &dyn ToInputArray, 
        k_fold: i32, 
        cgrid: Ptr<ParamGrid>, 
        gamma_grid: Ptr<ParamGrid>, 
        p_grid: Ptr<ParamGrid>, 
        nu_grid: Ptr<ParamGrid>, 
        coeff_grid: Ptr<ParamGrid>, 
        degree_grid: Ptr<ParamGrid>, 
        balanced: bool
    ) -> Result<bool> { ... }

}

Required methods

Provided methods

Type of a %SVM formulation. See SVM::Types. Default value is SVM::C_SVC.

See also

setType getType

Parameter inline formula of a kernel function. For SVM::POLY, SVM::RBF, SVM::SIGMOID or SVM::CHI2. Default value is 1.

See also

setGamma getGamma

Parameter coef0 of a kernel function. For SVM::POLY or SVM::SIGMOID. Default value is 0.

See also

setCoef0 getCoef0

Parameter degree of a kernel function. For SVM::POLY. Default value is 0.

See also

setDegree getDegree

Parameter C of a %SVM optimization problem. For SVM::C_SVC, SVM::EPS_SVR or SVM::NU_SVR. Default value is 0.

See also

setC getC

Parameter inline formula of a %SVM optimization problem. For SVM::NU_SVC, SVM::ONE_CLASS or SVM::NU_SVR. Default value is 0.

See also

setNu getNu

Parameter inline formula of a %SVM optimization problem. For SVM::EPS_SVR. Default value is 0.

See also

setP getP

Optional weights in the SVM::C_SVC problem, assigned to particular classes. They are multiplied by C so the parameter C of class i becomes classWeights(i) * C. Thus these weights affect the misclassification penalty for different classes. The larger weight, the larger penalty on misclassification of data from the corresponding class. Default value is empty Mat.

See also

setClassWeights getClassWeights

Termination criteria of the iterative %SVM training procedure which solves a partial case of constrained quadratic optimization problem. You can specify tolerance and/or the maximum number of iterations. Default value is TermCriteria( TermCriteria::MAX_ITER + TermCriteria::EPS, 1000, FLT_EPSILON );

See also

setTermCriteria getTermCriteria

Initialize with one of predefined kernels. See SVM::KernelTypes.

Initialize with custom kernel. See SVM::Kernel class for implementation details

Trains an %SVM with optimal parameters.

Parameters

  • data: the training data that can be constructed using TrainData::create or TrainData::loadFromCSV.
  • kFold: Cross-validation parameter. The training set is divided into kFold subsets. One subset is used to test the model, the others form the train set. So, the %SVM algorithm is executed kFold times.
  • Cgrid: grid for C
  • gammaGrid: grid for gamma
  • pGrid: grid for p
  • nuGrid: grid for nu
  • coeffGrid: grid for coeff
  • degreeGrid: grid for degree
  • balanced: If true and the problem is 2-class classification then the method creates more balanced cross-validation subsets that is proportions between classes in subsets are close to such proportion in the whole train dataset.

The method trains the %SVM model automatically by choosing the optimal parameters C, gamma, p, nu, coef0, degree. Parameters are considered optimal when the cross-validation estimate of the test set error is minimal.

If there is no need to optimize a parameter, the corresponding grid step should be set to any value less than or equal to 1. For example, to avoid optimization in gamma, set gammaGrid.step = 0, gammaGrid.minVal, gamma_grid.maxVal as arbitrary numbers. In this case, the value Gamma is taken for gamma.

And, finally, if the optimization in a parameter is required but the corresponding grid is unknown, you may call the function SVM::getDefaultGrid. To generate a grid, for example, for gamma, call SVM::getDefaultGrid(SVM::GAMMA).

This function works for the classification (SVM::C_SVC or SVM::NU_SVC) as well as for the regression (SVM::EPS_SVR or SVM::NU_SVR). If it is SVM::ONE_CLASS, no optimization is made and the usual %SVM with parameters specified in params is executed.

C++ default parameters

  • k_fold: 10
  • cgrid: getDefaultGrid(C)
  • gamma_grid: getDefaultGrid(GAMMA)
  • p_grid: getDefaultGrid(P)
  • nu_grid: getDefaultGrid(NU)
  • coeff_grid: getDefaultGrid(COEF)
  • degree_grid: getDefaultGrid(DEGREE)
  • balanced: false

Trains an %SVM with optimal parameters

Parameters

  • samples: training samples
  • layout: See ml::SampleTypes.
  • responses: vector of responses associated with the training samples.
  • kFold: Cross-validation parameter. The training set is divided into kFold subsets. One subset is used to test the model, the others form the train set. So, the %SVM algorithm is
  • Cgrid: grid for C
  • gammaGrid: grid for gamma
  • pGrid: grid for p
  • nuGrid: grid for nu
  • coeffGrid: grid for coeff
  • degreeGrid: grid for degree
  • balanced: If true and the problem is 2-class classification then the method creates more balanced cross-validation subsets that is proportions between classes in subsets are close to such proportion in the whole train dataset.

The method trains the %SVM model automatically by choosing the optimal parameters C, gamma, p, nu, coef0, degree. Parameters are considered optimal when the cross-validation estimate of the test set error is minimal.

This function only makes use of SVM::getDefaultGrid for parameter optimization and thus only offers rudimentary parameter options.

This function works for the classification (SVM::C_SVC or SVM::NU_SVC) as well as for the regression (SVM::EPS_SVR or SVM::NU_SVR). If it is SVM::ONE_CLASS, no optimization is made and the usual %SVM with parameters specified in params is executed.

C++ default parameters

  • k_fold: 10
  • cgrid: SVM::getDefaultGridPtr(SVM::C)
  • gamma_grid: SVM::getDefaultGridPtr(SVM::GAMMA)
  • p_grid: SVM::getDefaultGridPtr(SVM::P)
  • nu_grid: SVM::getDefaultGridPtr(SVM::NU)
  • coeff_grid: SVM::getDefaultGridPtr(SVM::COEF)
  • degree_grid: SVM::getDefaultGridPtr(SVM::DEGREE)
  • balanced: false

Implementations

Generates a grid for %SVM parameters.

Parameters

  • param_id: %SVM parameters IDs that must be one of the SVM::ParamTypes. The grid is generated for the parameter with this ID.

The function generates a grid for the specified parameter of the %SVM algorithm. The grid may be passed to the function SVM::trainAuto.

Generates a grid for %SVM parameters.

Parameters

  • param_id: %SVM parameters IDs that must be one of the SVM::ParamTypes. The grid is generated for the parameter with this ID.

The function generates a grid pointer for the specified parameter of the %SVM algorithm. The grid may be passed to the function SVM::trainAuto.

Creates empty model. Use StatModel::train to train the model. Since %SVM has several parameters, you may want to find the best parameters for your problem, it can be done with SVM::trainAuto.

Loads and creates a serialized svm from a file

Use SVM::save to serialize and store an SVM to disk. Load the SVM from this file again, by calling this function with the path to the file.

Parameters

  • filepath: path to serialized svm

Implementors