de.lmu.ifi.dbs.elki.datasource.parser

Class LibSVMFormatParser<V extends SparseNumberVector>

java.lang.Object

de.lmu.ifi.dbs.elki.datasource.parser.AbstractStreamingParser

de.lmu.ifi.dbs.elki.datasource.parser.NumberVectorLabelParser<V>

de.lmu.ifi.dbs.elki.datasource.parser.SparseNumberVectorLabelParser<V>

de.lmu.ifi.dbs.elki.datasource.parser.LibSVMFormatParser<V>

Type Parameters:

V - Vector type

All Implemented Interfaces:

BundleStreamSource, Parser, StreamingParser

@Title(value="libSVM Format Parser")
public class LibSVMFormatParser<V extends SparseNumberVector>
extends SparseNumberVectorLabelParser<V>

Parser to read libSVM format files.

The format of libSVM is roughly specified in the README given:

 <label> <index1>:<value1> <index2>:<value2> ...
 

i.e. a mandatory integer class label in the beginning followed by a classic sparse vector representation of the data. indexes are integers, starting at 1 (Note that ELKI uses 0-based indexing, so we will map these to index-1) to not always have a constant-0 dimension 0.

The libSVM FAQ states that you can also put comments into the file, separated by a hash: #, but they must not contain colons and are not officially supported.
ELKI will simply stop parsing a line when encountering a #.

Since:

0.7.0

Author:

Erich Schubert

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	LibSVMFormatParser.Parameterizer<V extends SparseNumberVector> Parameterization class.

Nested classes/interfaces inherited from interface de.lmu.ifi.dbs.elki.datasource.bundle.BundleStreamSource

BundleStreamSource.Event

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.regex.Pattern	COMMENT_PATTERN Comment pattern.
private static Logging	LOG Class logger.
static java.util.regex.Pattern	WHITESPACE_PATTERN LibSVM uses whitespace and colons for separation.

Fields inherited from class de.lmu.ifi.dbs.elki.datasource.parser.SparseNumberVectorLabelParser

labels, sparsefactory, values

Fields inherited from class de.lmu.ifi.dbs.elki.datasource.parser.NumberVectorLabelParser

attributes, columnnames, curlbl, curvec, factory, haslabels, maxdim, meta, mindim, nextevent, unique, warnedPrecision

Fields inherited from class de.lmu.ifi.dbs.elki.datasource.parser.AbstractStreamingParser

reader, tokenizer

Constructor Summary

Constructors

Constructor and Description
LibSVMFormatParser(SparseNumberVector.Factory<V> factory) Constructor.

Method Summary

Modifier and Type	Method and Description
protected Logging	getLogger() Get the logger for this class.
protected boolean	parseLineInternal() Internal method for parsing a single line.

Methods inherited from class de.lmu.ifi.dbs.elki.datasource.parser.SparseNumberVectorLabelParser

getTypeInformation

Methods inherited from class de.lmu.ifi.dbs.elki.datasource.parser.NumberVectorLabelParser

buildMeta, cleanup, createVector, data, getMeta, initStream, isLabelColumn, nextEvent

Methods inherited from class de.lmu.ifi.dbs.elki.datasource.parser.AbstractStreamingParser

asMultipleObjectsBundle, assignDBID, hasDBIDs, parse

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

LOG

private static final Logging LOG

Class logger.

WHITESPACE_PATTERN

public static final java.util.regex.Pattern WHITESPACE_PATTERN

LibSVM uses whitespace and colons for separation.

COMMENT_PATTERN

public static final java.util.regex.Pattern COMMENT_PATTERN

Comment pattern.

Constructor Detail

LibSVMFormatParser

public LibSVMFormatParser(SparseNumberVector.Factory<V> factory)

Constructor.

Parameters:

factory - Vector factory

Method Detail

parseLineInternal

protected boolean parseLineInternal()

Description copied from class: NumberVectorLabelParser

Internal method for parsing a single line. Used by both line based parsing as well as block parsing. This saves the building of meta data for each line.

Overrides:

parseLineInternal in class SparseNumberVectorLabelParser<V extends SparseNumberVector>

Returns:

true when a valid line was read, false on a label row.

getLogger

protected Logging getLogger()

Description copied from class: AbstractStreamingParser

Get the logger for this class.

Overrides:

getLogger in class SparseNumberVectorLabelParser<V extends SparseNumberVector>

Returns:

Logger.