tech.tablesaw.api

Class CategoryColumn

java.lang.Object

tech.tablesaw.columns.AbstractColumn

tech.tablesaw.api.CategoryColumn

All Implemented Interfaces:

Iterable<String>, IntConvertibleColumn, CategoryColumnUtils, Column, CategoryFilters, StringMapUtils, CategoryReduceUtils

public class CategoryColumn
extends AbstractColumn
implements CategoryFilters, CategoryColumnUtils, IntConvertibleColumn, Iterable<String>

A column that contains String values. They are assumed to be 'categorical' rather than free-form text, so are stored in an encoding that takes advantage of the expected repetition of string values.

Because the MISSING_VALUE for this column type is an empty string, there is little or no need for special handling of missing values in this class's methods.

Field Summary

Fields

Modifier and Type	Field and Description
static String	MISSING_VALUE
it.unimi.dsi.fastutil.ints.IntComparator	rowComparator

Fields inherited from interface tech.tablesaw.columns.CategoryColumnUtils

isMissing, isNotMissing

Constructor Summary

Constructors

Constructor and Description
CategoryColumn(ColumnMetadata metadata)
CategoryColumn(String name)
CategoryColumn(String name, int size)
CategoryColumn(String name, List<String> categories)
CategoryColumn(String name, String[] categories)

Method Summary

Modifier and Type	Method and Description
void	add(String stringValue)
void	addAll(List<String> stringValues) Add all the strings in the list to this column
void	append(Column column)
void	appendCell(String object)
CategoryColumn	appendString(CategoryColumn append) Return a copy of this column with the given string appended
CategoryColumn	appendString(String append) Return a copy of this column with the given string appended
byte[]	asBytes(int rowNumber) Returns the contents of the cell at rowNumber as a byte[]
Set<String>	asSet()
List<String>	bottom(int n) Returns the smallest ("bottom") n values in the column
int	byteSize() Returns the width of a cell in this column, in bytes
void	clear()
boolean	contains(String aString) Returns true if this column contains a cell with the given string, and false otherwise
static String	convert(String stringValue)
CategoryColumn	copy() Returns a deep copy of the receiver
Table	countByCategory()
int	countMissing() Returns the count of missing values in this column
int	countUnique() Returns the count of unique values in this column
it.unimi.dsi.fastutil.ints.IntArrayList	data() Returns the integers that back this column
DictionaryMap	dictionaryMap()
CategoryColumn	emptyCopy() Returns a copy of the receiver with no data.
CategoryColumn	emptyCopy(int rowSize) Returns an empty copy of the receiver, with its internal storage initialized to the given row size
String	get(int rowIndex) Returns the value at rowIndex in this column.
List<BooleanColumn>	getDummies() Returns a list of boolean columns suitable for use as dummy variables in, for example, regression analysis, selectWhere a column of categorical data must be encoded as a list of columns, such that each column represents a single category and indicates whether it is present (1) or not present (0)
int	getInt(int rowNumber)
String	getString(int row) Returns a string representation of the value at the given row
it.unimi.dsi.fastutil.ints.IntArrayList	getValues(it.unimi.dsi.fastutil.ints.IntArrayList indexes) Returns all the values associated with the given indexes
int[]	indexes() Returns the raw indexes that this column contains.
void	initializeWith(it.unimi.dsi.fastutil.ints.IntArrayList list, DictionaryMap map) Initializes this Column with the given values for performance
boolean	isEmpty() Returns true if the column has no data
Selection	isEqualTo(String string)
Selection	isIn(Collection<String> strings)
Selection	isIn(String... strings)
Selection	isMissing()
Selection	isNotEqualTo(String string)
Selection	isNotIn(Collection<String> strings)
Selection	isNotIn(String... strings)
Selection	isNotMissing()
Iterator<String>	iterator()
String	print()
CategoryColumn	replaceAll(String[] regexArray, String replacement) Creates a new column, replacing each string in this column with a new string formed by replacing any substring that matches the regex
it.unimi.dsi.fastutil.ints.IntComparator	rowComparator()
Selection	select(StringBiPredicate predicate, String value)
Selection	select(StringPredicate predicate)
CategoryColumn	selectIf(StringPredicate predicate)
void	set(int rowIndex, String stringValue)
int	size() Returns the number of elements (a.k.a.
void	sortAscending()
void	sortDescending()
Table	summary()
int[]	toIntArray()
IntColumn	toIntColumn()
CategoryColumn	tokenizeAndRemoveDuplicates()
CategoryColumn	tokenizeAndSort() Splits on Whitespace and returns the lexicographically sorted result
CategoryColumn	tokenizeAndSort(String separator)
List<String>	toList() Returns a List<String> representation of all the values in this column NOTE: Unless you really need a string consider using the column itself for large datasets as it uses much less memory
List<String>	top(int n) Returns the largest ("top") n values in the column
String	toString()
ColumnType	type() Returns this column's ColumnType
CategoryColumn	unique() Returns a new Column containing all the unique values in this column
it.unimi.dsi.fastutil.ints.IntArrayList	values() Returns the integer encoded value of each cell in this column.

Methods inherited from class tech.tablesaw.columns.AbstractColumn

columnMetadata, columnWidth, comment, difference, id, metadata, name, setComment, setName

Methods inherited from class java.lang.Object

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

Methods inherited from interface tech.tablesaw.filtering.text.CategoryFilters

empty, endsWith, equalToIgnoringCase, hasLengthEqualTo, isAlpha, isAlphaNumeric, isLongerThan, isLowerCase, isNumeric, isShorterThan, isUpperCase, matchesRegex, startsWith, stringContains

Methods inherited from interface tech.tablesaw.mapping.StringMapUtils

abbreviate, commonPrefix, commonSuffix, distance, join, lowerCase, padEnd, padStart, replaceAll, replaceFirst, substring, substring, trim, upperCase

Methods inherited from interface tech.tablesaw.reducing.CategoryReduceUtils

appendAll, appendAll

Methods inherited from interface tech.tablesaw.columns.Column

columnMetadata, columnWidth, comment, difference, first, first, id, last, last, metadata, name, setComment, setName, subset, title, toDoubleArray

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Methods inherited from interface tech.tablesaw.api.IntConvertibleColumn

asIntegerSet

Field Detail

MISSING_VALUE

public static final String MISSING_VALUE

rowComparator

public final it.unimi.dsi.fastutil.ints.IntComparator rowComparator

Constructor Detail

CategoryColumn

public CategoryColumn(String name)

CategoryColumn

public CategoryColumn(String name,
                      List<String> categories)

CategoryColumn

public CategoryColumn(String name,
                      String[] categories)

CategoryColumn

public CategoryColumn(ColumnMetadata metadata)

CategoryColumn

public CategoryColumn(String name,
                      int size)

Method Detail

convert

public static String convert(String stringValue)

type

public ColumnType type()

Description copied from interface: Column

Returns this column's ColumnType

Specified by:

type in interface Column

getString

public String getString(int row)

Description copied from interface: Column

Returns a string representation of the value at the given row

Specified by:

getString in interface Column

emptyCopy

public CategoryColumn emptyCopy()

Description copied from interface: Column

Returns a copy of the receiver with no data. The column name and type are the same

Specified by:

emptyCopy in interface Column

emptyCopy

public CategoryColumn emptyCopy(int rowSize)

Description copied from interface: Column

Returns an empty copy of the receiver, with its internal storage initialized to the given row size

Specified by:

emptyCopy in interface Column

sortAscending

public void sortAscending()

Specified by:

sortAscending in interface Column

sortDescending

public void sortDescending()

Specified by:

sortDescending in interface Column

size

public int size()

Returns the number of elements (a.k.a. rows or cells) in the column

Specified by:

size in interface Column

Specified by:

size in interface CategoryReduceUtils

get

public String get(int rowIndex)

Returns the value at rowIndex in this column. The index is zero-based.

Throws:

IndexOutOfBoundsException - if the given rowIndex is not in the column

toList

public List<String> toList()

Returns a List<String> representation of all the values in this column NOTE: Unless you really need a string consider using the column itself for large datasets as it uses much less memory

toIntArray

public int[] toIntArray()

Specified by:

toIntArray in interface IntConvertibleColumn

summary

public Table summary()

Specified by:

summary in interface Column

countByCategory

public Table countByCategory()

clear

public void clear()

Specified by:

clear in interface Column

set

public void set(int rowIndex,
                String stringValue)

countUnique

public int countUnique()

Description copied from interface: Column

Returns the count of unique values in this column

Specified by:

countUnique in interface Column

top

public List<String> top(int n)

Returns the largest ("top") n values in the column

Parameters:

n - The maximum number of records to return. The actual number will be smaller if n is greater than the number of observations in the column

Returns:

A list, possibly empty, of the largest observations

bottom

public List<String> bottom(int n)

Returns the smallest ("bottom") n values in the column

Parameters:

n - The maximum number of records to return. The actual number will be smaller if n is greater than the number of observations in the column

Returns:

A list, possibly empty, of the smallest n observations

add

public void add(String stringValue)

initializeWith

public void initializeWith(it.unimi.dsi.fastutil.ints.IntArrayList list,
                           DictionaryMap map)

Initializes this Column with the given values for performance

contains

public boolean contains(String aString)

Returns true if this column contains a cell with the given string, and false otherwise

getValues

public it.unimi.dsi.fastutil.ints.IntArrayList getValues(it.unimi.dsi.fastutil.ints.IntArrayList indexes)

Returns all the values associated with the given indexes

addAll

public void addAll(List<String> stringValues)

Add all the strings in the list to this column

appendCell

public void appendCell(String object)

Specified by:

appendCell in interface Column

Specified by:

appendCell in class AbstractColumn

rowComparator

public it.unimi.dsi.fastutil.ints.IntComparator rowComparator()

Specified by:

rowComparator in interface Column

isEmpty

public boolean isEmpty()

Description copied from interface: Column

Returns true if the column has no data

Specified by:

isEmpty in interface Column

isEqualTo

public Selection isEqualTo(String string)

isNotEqualTo

public Selection isNotEqualTo(String string)

getDummies

public List<BooleanColumn> getDummies()

Returns a list of boolean columns suitable for use as dummy variables in, for example, regression analysis, selectWhere a column of categorical data must be encoded as a list of columns, such that each column represents a single category and indicates whether it is present (1) or not present (0)

getInt

public int getInt(int rowNumber)

unique

public CategoryColumn unique()

Returns a new Column containing all the unique values in this column

Specified by:

unique in interface Column

data

public it.unimi.dsi.fastutil.ints.IntArrayList data()

Returns the integers that back this column

toIntColumn

public IntColumn toIntColumn()

dictionaryMap

public DictionaryMap dictionaryMap()

Specified by:

dictionaryMap in interface CategoryColumnUtils

toString

public String toString()

Overrides:

toString in class Object

indexes

public int[] indexes()

Returns the raw indexes that this column contains.

appendString

public CategoryColumn appendString(CategoryColumn append)

Return a copy of this column with the given string appended

Parameters:

append - the column to append

Returns:

the new column

appendString

public CategoryColumn appendString(String append)

Return a copy of this column with the given string appended

Parameters:

append - the string to append

Returns:

the new column

replaceAll

public CategoryColumn replaceAll(String[] regexArray,
                                 String replacement)

Creates a new column, replacing each string in this column with a new string formed by replacing any substring that matches the regex

Parameters:

regexArray - the regex array to replace

replacement - the replacement array

Returns:

the new column

tokenizeAndSort

public CategoryColumn tokenizeAndSort(String separator)

tokenizeAndSort

public CategoryColumn tokenizeAndSort()

Splits on Whitespace and returns the lexicographically sorted result

tokenizeAndRemoveDuplicates

public CategoryColumn tokenizeAndRemoveDuplicates()

print

public String print()

Specified by:

print in interface Column

isMissing

public Selection isMissing()

Specified by:

isMissing in interface Column

isNotMissing

public Selection isNotMissing()

Specified by:

isNotMissing in interface Column

select

public Selection select(StringPredicate predicate)

select

public Selection select(StringBiPredicate predicate,
                        String value)

copy

public CategoryColumn copy()

Description copied from interface: Column

Returns a deep copy of the receiver

Specified by:

copy in interface Column

append

public void append(Column column)

Specified by:

append in interface Column

countMissing

public int countMissing()

Returns the count of missing values in this column

Specified by:

countMissing in interface Column

iterator

public Iterator<String> iterator()

Specified by:

iterator in interface Iterable<String>

selectIf

public CategoryColumn selectIf(StringPredicate predicate)

asSet

public Set<String> asSet()

values

public it.unimi.dsi.fastutil.ints.IntArrayList values()

Returns the integer encoded value of each cell in this column. It can be used to lookup the mapped string in the lookupTable

Specified by:

values in interface CategoryColumnUtils

byteSize

public int byteSize()

Description copied from interface: Column

Returns the width of a cell in this column, in bytes

Specified by:

byteSize in interface Column

asBytes

public byte[] asBytes(int rowNumber)

Returns the contents of the cell at rowNumber as a byte[]

Specified by:

asBytes in interface Column

isIn

public Selection isIn(String... strings)

isIn

public Selection isIn(Collection<String> strings)

isNotIn

public Selection isNotIn(String... strings)

isNotIn

public Selection isNotIn(Collection<String> strings)