1Algorithm::SVM::DataSetU(s3e)r Contributed Perl DocumentaAtligoonrithm::SVM::DataSet(3)
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6 Algorithm::SVM::DataSet - A DataSet object for the Algorithm::SVM
7 Support Vector Machine.
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10 use Algorithm::SVM::DataSet;
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12 # Create a new dataset.
13 $ds = new Algorithm::SVM::DataSet(Label => 1,
14 Data => [ 0.12, 0.25, 0.33, 0.98 ]);
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16 # Retrieve/set the label.
17 $label = $ds->label();
18 $ds->label(1976);
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20 # Retrieve/set the attribute with an index of 0.
21 $attr = $ds->attribute(0);
22 $ds->attribute(0, 0.2621);
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25 Algorithm::SVM::DataSet is a representation of the datasets passed to
26 Algorithm::SVM object for training or classification. Each dataset has
27 an associated label, which classifies it as being part of a specific
28 group. A dataset object also has one or more key/value pairs
29 corresponding to the attributes that will be used for classification.
30 Values equal to zero will not be stored, and are returned by default if
31 no key/value pair exists. This sparse format saves memory, and is
32 treated in exactly the same way by libsvm.
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35 $ds = new Algorithm::SVM::DataSet(Label => 1,
36 Data => [ 0.12, 0.25, 0.33, 0.98 ]);
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38 The Algorithm::SVM::DataSet constructor accepts two optional named
39 parameters: Label and Data. Label is used to set the class to which
40 the dataset belongs, and Data is used to set any initial values. Data
41 should be an arrayref of numerical values. Each value in the arrayref
42 is assumed to have a key corresponding to its index in the array.
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44 ie) In the above example, 0.12 has a key of 0, 0.25 has a key of 1,
45 0.33 has a key of 2, etc.
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48 $label = $ds->label();
49 $ds->label(1976);
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51 The label method is used to set or retrieve the DataSets label value.
52 Parameters and return values should be numeric values.
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54 $attr = $ds->attribute(0);
55 $ds->attribute(0, 0.2621);
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57 The attribute method is used to set dataset attribute values. If a
58 single value is provided, the method will return the corresponding
59 value. If two value are provided, the method will set the first
60 parameter to the value of the second.
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62 $ds->asArray();
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64 The asArray method returns the contents of a DataSet object in an
65 efficient way. An optional parameter, $numAttr, can be used to pad the
66 array with zeros if the number of attributes is not known from the
67 beginning (e.g. when creating a word vector on the fly, since all keys
68 not given are automatically assumed to be zero)
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71 Matthew Laird <matt@brinkman.mbb.sfu.ca> Alexander K. Seewald
72 <alex@seewald.at>
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75 Algorithm::SVM
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79perl v5.36.0 2022-08-18 Algorithm::SVM::DataSet(3)