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get_sample_class_svmGetSampleClassSvmGetSampleClassSvmget_sample_class_svmT_get_sample_class_svm🔗

Short description🔗

get_sample_class_svmGetSampleClassSvmGetSampleClassSvmget_sample_class_svmT_get_sample_class_svm — Return a training sample from the training data of a support vector machine.

Signature🔗

get_sample_class_svm( class_svm SVMHandle, integer IndexSample, out real Features, out integer Target )void GetSampleClassSvm( const HTuple& SVMHandle, const HTuple& IndexSample, HTuple* Features, HTuple* Target )static void HOperatorSet.GetSampleClassSvm( HTuple SVMHandle, HTuple indexSample, out HTuple features, out HTuple target )def get_sample_class_svm( svmhandle: HHandle, index_sample: int ) -> Tuple[Sequence[float], int]

Herror T_get_sample_class_svm( const Htuple SVMHandle, const Htuple IndexSample, Htuple* Features, Htuple* Target )

HTuple HClassSvm::GetSampleClassSvm( Hlong IndexSample, Hlong* Target ) const

HTuple HClassSvm.GetSampleClassSvm( int indexSample, out int target )

Description🔗

get_sample_class_svmGetSampleClassSvm reads out a training sample from the support vector machine (SVM) given by SVMHandleSVMHandlesvmhandle that was added with add_sample_class_svmAddSampleClassSvm or read_samples_class_svmReadSamplesClassSvm. The index of the sample is specified with IndexSampleindexSampleindex_sample. The index is counted from 0, i.e., IndexSampleindexSampleindex_sample must be a number between 0 and NumSamplesnumSamplesnum_samples \(-\) 1, where NumSamplesnumSamplesnum_samples can be determined with get_sample_num_class_svmGetSampleNumClassSvm. The training sample is returned in Featuresfeaturesfeatures and Targettargettarget. Featuresfeaturesfeatures is a feature vector of length NumFeaturesnumFeaturesnum_features (see create_class_svmCreateClassSvm), while Targettargettarget is the index of the class, ranging between 0 and NumClassesnumClassesnum_classes-1 (see add_sample_class_svmAddSampleClassSvm).

get_sample_class_svmGetSampleClassSvm can, for example, be used to reclassify the training data with classify_class_svmClassifyClassSvm in order to determine which training samples, if any, are classified incorrectly.

Execution information🔗

Execution information

  • Multithreading type: reentrant (runs in parallel with non-exclusive operators).

  • Multithreading scope: global (may be called from any thread).

  • Processed without parallelization.

Parameters🔗

SVMHandleSVMHandlesvmhandle (input_control) class_svm → (handle)HTuple (HHandle)HClassSvm, HTuple (IntPtr)HHandleHtuple (handle)

SVM handle.

IndexSampleindexSampleindex_sample (input_control) integer → (integer)HTuple (Hlong)HTuple (int / long)intHtuple (Hlong)

Number of the stored training sample.

Featuresfeaturesfeatures (output_control) real-array → (real)HTuple (double)HTuple (double)Sequence[float]Htuple (double)

Feature vector of the training sample.

Targettargettarget (output_control) integer → (integer)HTuple (Hlong)HTuple (int / long)intHtuple (Hlong)

Target vector of the training sample.

Example🔗

(HDevelop)

* Train an SVM
create_class_svm (NumFeatures, 'rbf', 0.01, 0.01, NumClasses,\
                  'one-versus-all', 'normalization', NumFeatures,\
                  SVMHandle)
read_samples_class_svm (SVMHandle, 'samples.mtf')
train_class_svm (SVMHandle, 0.001, 'default')
* Reclassify the training samples
get_sample_num_class_svm (SVMHandle, NumSamples)
for I := 0 to NumSamples-1 by 1
    get_sample_class_svm (SVMHandle, I, Data, Target)
    classify_class_svm (SVMHandle, Data, 1, Class)
    if (Class != Target)
        * Sample has been classified incorrectly
    endif
endfor

Result🔗

If the parameters are valid the operator get_sample_class_svmGetSampleClassSvm returns the value 2 (H_MSG_TRUE). If necessary, an exception is raised.

Combinations with other operators🔗

Combinations

Possible predecessors

add_sample_class_svmAddSampleClassSvm, read_samples_class_svmReadSamplesClassSvm, get_sample_num_class_svmGetSampleNumClassSvm, get_support_vector_class_svmGetSupportVectorClassSvm

Possible successors

classify_class_svmClassifyClassSvm

See also

create_class_svmCreateClassSvm

Module🔗

Foundation