Package tech.tablesaw.columns

Class AbstractColumn<C extends Column<T>,T>

java.lang.Object

tech.tablesaw.columns.AbstractColumn<C,T>

All Implemented Interfaces:

Iterable<T>, Comparator<T>, Column<T>

Direct Known Subclasses:

AbstractStringColumn, BooleanColumn, DateColumn, DateTimeColumn, InstantColumn, NumberColumn, TimeColumn

public abstract class AbstractColumn<C extends Column<T>,T>
extends Object
implements Column<T>

Partial implementation of the Column interface

Field Summary

Fields

Modifier and Type	Field	Description
static final int	DEFAULT_ARRAY_SIZE

Constructor Summary

Constructors

Constructor	Description
AbstractColumn(ColumnType type, String name, AbstractColumnParser<T> parser)	Constructs a column with the given ColumnType, name, and AbstractColumnParser

Method Summary

Modifier and Type	Method	Description
StringColumn	asStringColumn()	Returns a StringColumn consisting of the (unformatted) String representation of this column values
abstract Column<T>	emptyCopy()	Returns a copy of the receiver with no data.
C	filter(Predicate<? super T> test)	Returns a new Column of the same type with only those rows satisfying the predicate
C	first(int numRows)	Returns a column of the same type containing the first numRows of this column.
int	indexOf(Object o)	Returns the index of the first occurrence of o in the column or -1 if the element is not in the column.
C	inRange(int start, int end)	Returns a column containing the rows in this column beginning with start inclusive, and ending with end exclusive
C	last(int numRows)	Returns a column of the same type containing the last numRows of this column.
C	map(Function<? super T,? extends T> fun)	Maps the function across all rows, appending the results to a new Column of the same type
C	max(Column<T> other)	Returns a column containing the element-wise min between this column and other column
C	min(Column<T> other)	Returns a column containing the element-wise min between this column and other column
String	name()	Returns the column's name.
AbstractColumnParser<T>	parser()	Returns the parser used by Column.appendCell(String) ()}.
C	sampleN(int n)	Returns a column containing a random sample of the values in this column
C	sampleX(double proportion)	Returns a table consisting of randomly selected values from this column.
C	set(Selection rowSelection, T newValue)	Conditionally update this column, replacing current values with newValue for all rows where the current value matches the selection criteria
C	set(Selection condition, Column<T> other)	Updates this column where values matching the selection are replaced with the corresponding value from the given column
C	setName(String name)	Sets the columns name to the given string
C	setParser(AbstractColumnParser<T> parser)	Sets the parser used by Column.appendCell(String)
C	sorted(Comparator<? super T> comp)	Returns a new Column of the same type sorted according to the provided Comparator
C	subset(int[] rows)	Return a column of the same type containing just those elements whose indexes are included in the given array
String	toString()
ColumnType	type()	Returns this column's ColumnType

Methods inherited from class java.lang.Object

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

Methods inherited from interface tech.tablesaw.columns.Column

allMatch, anyMatch, append, append, append, appendCell, appendCell, appendMissing, appendObj, asBytes, asList, asObjectArray, asSet, byteSize, clear, columnWidth, contains, copy, count, count, countMissing, countUnique, emptyCopy, equals, get, getString, getUnformattedString, interpolate, isEmpty, isMissing, isMissing, isNotMissing, lag, lead, map, mapInto, max, min, noneMatch, print, reduce, reduce, removeMissing, rolling, rowComparator, set, set, set, set, setMissing, setMissingTo, size, sortAscending, sortDescending, summary, title, unique, valueHash, where

Methods inherited from interface java.util.Comparator

compare, equals, reversed, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Field Details

DEFAULT_ARRAY_SIZE

public static final int DEFAULT_ARRAY_SIZE

See Also:

• Constant Field Values

Constructor Details

AbstractColumn

public AbstractColumn(ColumnType type,
 String name,
 AbstractColumnParser<T> parser)

Constructs a column with the given ColumnType, name, and AbstractColumnParser

Method Details

name

public String name()

Returns the column's name.

Specified by:

name in interface Column<C extends Column<T>>

Returns:

name as String

setName

public C setName(String name)

Sets the columns name to the given string

Specified by:

setName in interface Column<C extends Column<T>>

Parameters:

name - The new name MUST be unique for any table containing this column

Returns:

this Column to allow method chaining

parser

public AbstractColumnParser<T> parser()

Returns the parser used by Column.appendCell(String) ()}.

Specified by:

parser in interface Column<C extends Column<T>>

Returns:

AbstractColumnParser

setParser

public C setParser(AbstractColumnParser<T> parser)

Sets the parser used by Column.appendCell(String)

Specified by:

setParser in interface Column<C extends Column<T>>

Parameters:

parser - a column parser that converts text input to the column data type

Returns:

this Column to allow method chaining

type

public ColumnType type()

Returns this column's ColumnType

Specified by:

type in interface Column<C extends Column<T>>

Returns:

ColumnType

emptyCopy

public abstract Column<T> emptyCopy()

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

Specified by:

emptyCopy in interface Column<C extends Column<T>>

Returns:

a empty copy of Column

filter

public C filter(Predicate<? super T> test)

Returns a new Column of the same type with only those rows satisfying the predicate

Specified by:

filter in interface Column<C extends Column<T>>

Parameters:

test - the predicate

Returns:

a new Column of the same type with only those rows satisfying the predicate

sorted

public C sorted(Comparator<? super T> comp)

Returns a new Column of the same type sorted according to the provided Comparator

Specified by:

sorted in interface Column<C extends Column<T>>

Parameters:

comp - the Comparator

Returns:

a sorted Column

map

public C map(Function<? super T,? extends T> fun)

Maps the function across all rows, appending the results to a new Column of the same type

Specified by:

map in interface Column<C extends Column<T>>

Parameters:

fun - function to map

Returns:

the Column with the results

min

public C min(Column<T> other)

Returns a column containing the element-wise min between this column and other column

TODO(lwhite) Override in column subtypes for better performance

Specified by:

min in interface Column<C extends Column<T>>

max

public C max(Column<T> other)

Returns a column containing the element-wise min between this column and other column

TODO(lwhite) Override in column subtypes for better performance

Specified by:

max in interface Column<C extends Column<T>>

set

public C set(Selection condition,
 Column<T> other)

Updates this column where values matching the selection are replaced with the corresponding value from the given column

Specified by:

set in interface Column<C extends Column<T>>

set

public C set(Selection rowSelection,
 T newValue)

Conditionally update this column, replacing current values with newValue for all rows where the current value matches the selection criteria

Specified by:

set in interface Column<C extends Column<T>>

first

public C first(int numRows)

Returns a column of the same type containing the first numRows of this column.

Specified by:

first in interface Column<C extends Column<T>>

last

public C last(int numRows)

Returns a column of the same type containing the last numRows of this column.

Specified by:

last in interface Column<C extends Column<T>>

sampleN

public C sampleN(int n)

Returns a column containing a random sample of the values in this column

Specified by:

sampleN in interface Column<C extends Column<T>>

Parameters:

n - the number of values to select

Returns:

A column of the same type as the receiver

sampleX

public C sampleX(double proportion)

Returns a table consisting of randomly selected values from this column. The sample size is based on the given proportion of the total number of cells in this column

Specified by:

sampleX in interface Column<C extends Column<T>>

Parameters:

proportion - The proportion to go in the sample

subset

public C subset(int[] rows)

Return a column of the same type containing just those elements whose indexes are included in the given array

Specified by:

subset in interface Column<C extends Column<T>>

inRange

public C inRange(int start,
 int end)

Returns a column containing the rows in this column beginning with start inclusive, and ending with end exclusive

Specified by:

inRange in interface Column<C extends Column<T>>

toString

public String toString()

Overrides:

toString in class Object

asStringColumn

public StringColumn asStringColumn()

Returns a StringColumn consisting of the (unformatted) String representation of this column values

Specified by:

asStringColumn in interface Column<C extends Column<T>>

Returns:

a StringColumn built using the column Column.getUnformattedString(int) method

indexOf

public int indexOf(Object o)

Returns the index of the first occurrence of o in the column or -1 if the element is not in the column.

Specified by:

indexOf in interface Column<C extends Column<T>>