CategoryColumn (tablesaw-core 0.12.0 API)

java.lang.Object
- tech.tablesaw.columns.AbstractColumn
- - tech.tablesaw.api.CategoryColumn

All Implemented Interfaces:

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

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

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

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`void`	`add(String stringValue)` Deprecated. Use append(String value) instead
`void`	`addAll(List<String> stringValues)` Add all the strings in the list to this column
`void`	`append(Column column)`
`void`	`append(String value)` Added for naming consistency with all other columns
`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[]
`int[]`	`asIntArray()`
`IntColumn`	`asIntColumn()`
`List<String>`	`asList()` 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
`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(CategoryColumn other)`
`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)`
`void`	`set(String newValue, Selection rowSelection)` Conditionally update this column, replacing current values with newValue for all rows where the current value matches the selection criteria Examples: myCatColumn.set("Dog", myCatColumn.isEqualTo("Cat")); // no more cats myCatColumn.set("Fox", myCatColumn.isMissing()); // no more missing values
`int`	`size()` Returns the number of elements (a.k.a.
`void`	`sortAscending()`
`void`	`sortDescending()`
`Table`	`summary()`
`CategoryColumn`	`tokenizeAndRemoveDuplicates()`
`CategoryColumn`	`tokenizeAndSort()` Splits on Whitespace and returns the lexicographically sorted result.
`CategoryColumn`	`tokenizeAndSort(String separator)`
`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.aggregate.CategoryReduceUtils
appendAll, appendAll

Methods inherited from interface tech.tablesaw.columns.Column
asDoubleArray, columnMetadata, columnWidth, comment, difference, first, first, id, last, last, metadata, name, rolling, setComment, setName, subset, title

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,
                      String[] categories)
```
  - CategoryColumn
```
public CategoryColumn(String name,
                      List<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
    
    Returns:
    
    ColumnType
  - 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
    
    Parameters:
    
    row - The index of the row.
    
    Returns:
    
    value as String
  - 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
    
    Returns:
    
    a empty copy of 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
    
    Parameters:
    
    rowSize - the initial row size
    
    Returns:
    
    a 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 CategoryReduceUtils
    
    Specified by:
    
    size in interface Column
    
    Returns:
    
    size as int
  - get
```
public String get(int rowIndex)
```
    Returns the value at rowIndex in this column. The index is zero-based.
    
    Parameters:
    
    rowIndex - index of the row
    
    Returns:
    
    value as String
    
    Throws:
    
    IndexOutOfBoundsException - if the given rowIndex is not in the column
  - asList
```
public List<String> asList()
```
    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
    
    Returns:
    
    values as a list of String.
  - asIntArray
```
public int[] asIntArray()
```
    Specified by:
    
    asIntArray 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
  - isEqualTo
```
public Selection isEqualTo(CategoryColumn other)
```
  - set
```
public void set(String newValue,
                Selection rowSelection)
```
    Conditionally update this column, replacing current values with newValue for all rows where the current value matches the selection criteria Examples: myCatColumn.set("Dog", myCatColumn.isEqualTo("Cat")); // no more cats myCatColumn.set("Fox", myCatColumn.isMissing()); // no more missing values
  - 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
    
    Returns:
    
    unique values as int
  - 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)
```
    Deprecated. Use append(String value) instead
  - 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
    
    Parameters:
    
    aString - the value to look for
    
    Returns:
    
    true if contains, false otherwhise
  - 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.
    
    Parameters:
    
    indexes - the indexes
    
    Returns:
    
    values as IntArrayList
  - addAll
```
public void addAll(List<String> stringValues)
```
    Add all the strings in the list to this column
    
    Parameters:
    
    stringValues - a list of values
  - 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
    
    Returns:
    
    true if empty, false if not
  - 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)
    
    Returns:
    
    a list of BooleanColumn
  - 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
    
    Returns:
    
    a column with unique values.
  - data
```
public it.unimi.dsi.fastutil.ints.IntArrayList data()
```
    Returns the integers that back this column.
    
    Returns:
    
    data as IntArrayList
  - asIntColumn
```
public IntColumn asIntColumn()
```
  - 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.
    
    Returns:
    
    indexes as int[]
  - 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.
    
    Returns:
    
    a CategoryColumn
  - 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
    
    Returns:
    
    a 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
    
    Returns:
    
    missing values as int
  - 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
    
    Returns:
    
    values a IntArrayList
  - 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
    
    Returns:
    
    width in bytes
  - asBytes
```
public byte[] asBytes(int rowNumber)
```
    Returns the contents of the cell at rowNumber as a byte[]
    
    Specified by:
    
    asBytes in interface Column
    
    Parameters:
    
    rowNumber - index of the row
    
    Returns:
    
    content as byte[]
  - isIn
```
public Selection isIn(String... strings)
```
  - isIn
```
public Selection isIn(Collection<String> strings)
```
  - append
```
public void append(String value)
```
    Added for naming consistency with all other columns
  - isNotIn
```
public Selection isNotIn(String... strings)
```
  - isNotIn
```
public Selection isNotIn(Collection<String> strings)
```

Class CategoryColumn

Field Summary

Fields inherited from interface tech.tablesaw.columns.CategoryColumnUtils

Constructor Summary

Method Summary

Methods inherited from class tech.tablesaw.columns.AbstractColumn

Methods inherited from class java.lang.Object

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

Methods inherited from interface tech.tablesaw.mapping.StringMapUtils

Methods inherited from interface tech.tablesaw.aggregate.CategoryReduceUtils

Methods inherited from interface tech.tablesaw.columns.Column

Methods inherited from interface java.lang.Iterable

Methods inherited from interface tech.tablesaw.api.IntConvertibleColumn

Field Detail

MISSING_VALUE

rowComparator

Constructor Detail

CategoryColumn

CategoryColumn

CategoryColumn

CategoryColumn

CategoryColumn

Method Detail

convert

type

getString

emptyCopy

emptyCopy

sortAscending

sortDescending

size

get

asList

asIntArray

summary

countByCategory

clear

isEqualTo

set

set

countUnique

top

bottom

add

initializeWith

contains

getValues

addAll

appendCell

rowComparator

isEmpty

isEqualTo

isNotEqualTo

getDummies

getInt

unique

data

asIntColumn

dictionaryMap

toString

indexes

appendString

appendString

replaceAll

tokenizeAndSort

tokenizeAndSort

tokenizeAndRemoveDuplicates

print

isMissing

isNotMissing

select

select

copy

append

countMissing

iterator

selectIf

asSet

values

byteSize