weka.core.converters
Class CSVLoader

java.lang.Object
  weka.core.converters.AbstractLoader
      weka.core.converters.AbstractFileLoader
          weka.core.converters.CSVLoader

All Implemented Interfaces:

Serializable, BatchConverter, FileSourcedConverter, Loader, EnvironmentHandler, OptionHandler, RevisionHandler

public class CSVLoader
extends AbstractFileLoader
implements BatchConverter, OptionHandler

Reads a source that is in comma separated format (the default). One can also change the column separator from comma to tab or another character. Assumes that the first row in the file determines the number of and names of the attributes.

Valid options are:

 -H
  No header row present in the data.

 -N <range>
  The range of attributes to force type to be NOMINAL.
  'first' and 'last' are accepted as well.
  Examples: "first-last", "1,4,5-27,50-last"
  (default: -none-)

 -S <range>
  The range of attribute to force type to be STRING.
  'first' and 'last' are accepted as well.
  Examples: "first-last", "1,4,5-27,50-last"
  (default: -none-)

 -D <range>
  The range of attribute to force type to be DATE.
  'first' and 'last' are accepted as well.
  Examples: "first-last", "1,4,5-27,50-last"
  (default: -none-)

 -format <date format>
  The date formatting string to use to parse date values.
  (default: "yyyy-MM-dd'T'HH:mm:ss")

 -M <str>
  The string representing a missing value.
  (default: ?)

 -F <separator>
  The field separator to be used.
  '\t' can be used as well.
  (default: ',')

Version:

$Revision: 8034 $

Author:

Mark Hall (mhall@cs.waikato.ac.nz)

See Also:

Loader, Serialized Form

Field Summary

static String

FILE_EXTENSION the file extension.

Fields inherited from class weka.core.converters.AbstractFileLoader

FILE_EXTENSION_COMPRESSED

Fields inherited from interface weka.core.converters.Loader

BATCH, INCREMENTAL, NONE

Constructor Summary

CSVLoader()
default constructor.

Method Summary

String	dateAttributesTipText() Returns the tip text for this property.
String	dateFormatTipText() Returns the tip text for this property.
String	fieldSeparatorTipText() Returns the tip text for this property.
Instances	getDataSet() Return the full data set.
String	getDateAttributes() Returns the current attribute range to be forced to type date.
String	getDateFormat() Get the format to use for parsing date values.
String	getFieldSeparator() Returns the character used as column separator.
String	getFileDescription() Returns a description of the file type.
String	getFileExtension() Get the file extension used for arff files.
String[]	getFileExtensions() Gets all the file extensions used for this type of file.
String	getMissingValue() Returns the current placeholder for missing values.
Instance	getNextInstance(Instances structure) CSVLoader is unable to process a data set incrementally.
boolean	getNoHeaderRowPresent() Get whether there is no header row in the data.
String	getNominalAttributes() Returns the current attribute range to be forced to type nominal.
String[]	getOptions() Gets the current settings of the Loader.
String	getRevision() Returns the revision string.
String	getStringAttributes() Returns the current attribute range to be forced to type string.
Instances	getStructure() Determines and returns (if possible) the structure (internally the header) of the data set as an empty set of instances.
String	globalInfo() Returns a string describing this attribute evaluator.
Enumeration	listOptions() Returns an enumeration describing the available options.
static void	main(String[] args) Main method.
String	missingValueTipText() Returns the tip text for this property.
String	noHeaderRowPresentTipText() Returns the tip text for this property.
String	nominalAttributesTipText() Returns the tip text for this property.
void	reset() Resets the Loader ready to read a new data set or the same data set again.
void	setDateAttributes(String value) Set the attribute range to be forced to type date.
void	setDateFormat(String value) Set the format to use for parsing date values.
void	setFieldSeparator(String value) Sets the character used as column separator.
void	setMissingValue(String value) Sets the placeholder for missing values.
void	setNoHeaderRowPresent(boolean b) Set whether there is no header row in the data.
void	setNominalAttributes(String value) Sets the attribute range to be forced to type nominal.
void	setOptions(String[] options) Parses a given list of options.
void	setSource(File file) Resets the Loader object and sets the source of the data set to be the supplied File object.
void	setSource(InputStream input) Resets the Loader object and sets the source of the data set to be the supplied Stream object.
void	setStringAttributes(String value) Sets the attribute range to be forced to type string.
String	stringAttributesTipText() Returns the tip text for this property.

Methods inherited from class weka.core.converters.AbstractFileLoader

getUseRelativePath, retrieveFile, runFileLoader, setEnvironment, setFile, setUseRelativePath, useRelativePathTipText

Methods inherited from class weka.core.converters.AbstractLoader

setRetrieval

Methods inherited from class java.lang.Object

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

Field Detail

FILE_EXTENSION

public static String FILE_EXTENSION

the file extension.

Constructor Detail

CSVLoader

public CSVLoader()

default constructor.

Method Detail

getFileExtension

public String getFileExtension()

Get the file extension used for arff files.

Specified by:

getFileExtension in interface FileSourcedConverter

Returns:

the file extension

getFileDescription

public String getFileDescription()

Returns a description of the file type.

Specified by:

getFileDescription in interface FileSourcedConverter

Returns:

a short file description

getFileExtensions

public String[] getFileExtensions()

Gets all the file extensions used for this type of file.

Specified by:

getFileExtensions in interface FileSourcedConverter

Returns:

the file extensions

globalInfo

public String globalInfo()

Returns a string describing this attribute evaluator.

Returns:

a description of the evaluator suitable for displaying in the explorer/experimenter gui

listOptions

public Enumeration listOptions()

Returns an enumeration describing the available options.

Specified by:

listOptions in interface OptionHandler

Returns:

an enumeration of all the available options.

setOptions

public void setOptions(String[] options)
                throws Exception

Parses a given list of options.

Valid options are:

 -H
  No header row present in the data.

 -N <range>
  The range of attributes to force type to be NOMINAL.
  'first' and 'last' are accepted as well.
  Examples: "first-last", "1,4,5-27,50-last"
  (default: -none-)

 -S <range>
  The range of attribute to force type to be STRING.
  'first' and 'last' are accepted as well.
  Examples: "first-last", "1,4,5-27,50-last"
  (default: -none-)

 -D <range>
  The range of attribute to force type to be DATE.
  'first' and 'last' are accepted as well.
  Examples: "first-last", "1,4,5-27,50-last"
  (default: -none-)

 -format <date format>
  The date formatting string to use to parse date values.
  (default: "yyyy-MM-dd'T'HH:mm:ss")

 -M <str>
  The string representing a missing value.
  (default: ?)

 -F <separator>
  The field separator to be used.
  '\t' can be used as well.
  (default: ',')

Specified by:

setOptions in interface OptionHandler

Parameters:

options - the list of options as an array of strings

Throws:

Exception - if an option is not supported

getOptions

public String[] getOptions()

Gets the current settings of the Loader.

Specified by:

getOptions in interface OptionHandler

Returns:

an array of strings suitable for passing to setOptions

noHeaderRowPresentTipText

public String noHeaderRowPresentTipText()

Returns the tip text for this property.

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

setNoHeaderRowPresent

public void setNoHeaderRowPresent(boolean b)

Set whether there is no header row in the data.

Parameters:

b - true if there is no header row in the data

getNoHeaderRowPresent

public boolean getNoHeaderRowPresent()

Get whether there is no header row in the data.

Returns:

true if there is no header row in the data

setNominalAttributes

public void setNominalAttributes(String value)

Sets the attribute range to be forced to type nominal.

Parameters:

value - the range

getNominalAttributes

public String getNominalAttributes()

Returns the current attribute range to be forced to type nominal.

Returns:

the range

nominalAttributesTipText

public String nominalAttributesTipText()

Returns the tip text for this property.

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

setStringAttributes

public void setStringAttributes(String value)

Sets the attribute range to be forced to type string.

Parameters:

value - the range

getStringAttributes

public String getStringAttributes()

Returns the current attribute range to be forced to type string.

Returns:

the range

stringAttributesTipText

public String stringAttributesTipText()

Returns the tip text for this property.

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

setDateAttributes

public void setDateAttributes(String value)

Set the attribute range to be forced to type date.

Parameters:

value - the range

getDateAttributes

public String getDateAttributes()

Returns the current attribute range to be forced to type date.

Returns:

the range.

dateAttributesTipText

public String dateAttributesTipText()

Returns the tip text for this property.

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

setDateFormat

public void setDateFormat(String value)

Set the format to use for parsing date values.

Parameters:

value - the format to use.

getDateFormat

public String getDateFormat()

Get the format to use for parsing date values.

Returns:

the format to use for parsing date values.

dateFormatTipText

public String dateFormatTipText()

Returns the tip text for this property.

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

setMissingValue

public void setMissingValue(String value)

Sets the placeholder for missing values.

Parameters:

value - the placeholder

getMissingValue

public String getMissingValue()

Returns the current placeholder for missing values.

Returns:

the placeholder

missingValueTipText

public String missingValueTipText()

Returns the tip text for this property.

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

setFieldSeparator

public void setFieldSeparator(String value)

Sets the character used as column separator.

Parameters:

value - the character to use

getFieldSeparator

public String getFieldSeparator()

Returns the character used as column separator.

Returns:

the character to use

fieldSeparatorTipText

public String fieldSeparatorTipText()

Returns the tip text for this property.

Returns:

tip text for this property suitable for displaying in the explorer/experimenter gui

setSource

public void setSource(InputStream input)
               throws IOException

Resets the Loader object and sets the source of the data set to be the supplied Stream object.

Specified by:

setSource in interface Loader

Overrides:

setSource in class AbstractLoader

Parameters:

input - the input stream

Throws:

IOException - if an error occurs

setSource

public void setSource(File file)
               throws IOException

Resets the Loader object and sets the source of the data set to be the supplied File object.

Specified by:

setSource in interface Loader

Overrides:

setSource in class AbstractFileLoader

Parameters:

file - the source file.

Throws:

IOException - if an error occurs

getStructure

public Instances getStructure()
                       throws IOException

Determines and returns (if possible) the structure (internally the header) of the data set as an empty set of instances.

Specified by:

getStructure in interface Loader

Specified by:

getStructure in class AbstractLoader

Returns:

the structure of the data set as an empty set of Instances

Throws:

IOException - if an error occurs

getDataSet

public Instances getDataSet()
                     throws IOException

Return the full data set. If the structure hasn't yet been determined by a call to getStructure then method should do so before processing the rest of the data set.

Specified by:

getDataSet in interface Loader

Specified by:

getDataSet in class AbstractLoader

Returns:

the structure of the data set as an empty set of Instances

Throws:

IOException - if there is no source or parsing fails

getNextInstance

public Instance getNextInstance(Instances structure)
                         throws IOException

CSVLoader is unable to process a data set incrementally.

Specified by:

getNextInstance in interface Loader

Specified by:

getNextInstance in class AbstractLoader

Parameters:

structure - ignored

Returns:

never returns without throwing an exception

Throws:

IOException - always. CSVLoader is unable to process a data set incrementally.

reset

public void reset()
           throws IOException

Resets the Loader ready to read a new data set or the same data set again.

Specified by:

reset in interface Loader

Overrides:

reset in class AbstractFileLoader

Throws:

IOException - if something goes wrong

getRevision

public String getRevision()

Returns the revision string.

Specified by:

getRevision in interface RevisionHandler

Returns:

the revision

main

public static void main(String[] args)

Main method.

Parameters:

args - should contain the name of an input file.