tech.tablesaw.table

Class Relation

java.lang.Object

tech.tablesaw.table.Relation

Direct Known Subclasses:

Table, TemporaryView

public abstract class Relation
extends Object

A tabular data structure like a table in a relational database, but not formally implementing the relational algebra

Constructor Summary

Constructors

Constructor and Description
Relation()

Method Summary

Modifier and Type	Method and Description
abstract Relation	addColumn(Column... cols)
BooleanColumn	booleanColumn(int columnIndex)
BooleanColumn	booleanColumn(String columnName)
CategoryColumn	categoryColumn(int columnIndex)
CategoryColumn	categoryColumn(String columnName)
abstract void	clear() Clears all the dat in the relation, leaving the structure intact
abstract Column	column(int columnIndex) Returns the column at columnIndex (0-based)
Column	column(String columnName) Returns the column with the given columnName, ignoring case
abstract int	columnCount() Returns the number of columns in the relation
abstract int	columnIndex(Column col) Returns the index of the given column
int	columnIndex(String columnName) Returns the index of the column with the given columnName
abstract List<String>	columnNames()
abstract List<Column>	columns() Returns a list of all the columns in the relation
ColumnType[]	columnTypes() Returns an array of the column types of all columns in the relation, including duplicates as appropriate, and maintaining order
int[]	colWidths() Returns an array of column widths for printing tables
DateColumn	dateColumn(int columnIndex)
DateColumn	dateColumn(String columnName)
DateTimeColumn	dateTimeColumn(int columnIndex)
DateTimeColumn	dateTimeColumn(String columnName)
DoubleColumn	doubleColumn(int columnIndex)
DoubleColumn	doubleColumn(String columnName)
abstract Table	first(int nRows)
FloatColumn	floatColumn(int columnIndex)
FloatColumn	floatColumn(String columnName)
abstract String	get(int r, int c) Returns a String representing the value found at column index c and row index r
IntColumn	intColumn(int columnIndex)
IntColumn	intColumn(String columnName)
boolean	isEmpty()
LongColumn	longColumn(int columnIndex)
LongColumn	longColumn(String columnName)
abstract String	name() Returns the name of this relation
NumericColumn	nCol(int columnIndex) Returns the column with the given name cast to a NumericColumn
NumericColumn	nCol(String columnName) Returns the column with the given name cast to a NumericColumn
NumericColumn	numericColumn(int columnIndex)
NumericColumn	numericColumn(String columnName)
String	print()
String	print(int rowLimit)
Relation	removeColumn(int columnIndex)
abstract Relation	removeColumns(Column... columns) Removes the given columns from the receiver
Relation	removeColumns(String... columnName)
abstract int	rowCount() Returns the number of rows in the relation
abstract Relation	setName(String name)
String	shape()
ShortColumn	shortColumn(int columnIndex)
ShortColumn	shortColumn(String columnName)
Table	structure()
String	summary()
TimeColumn	timeColumn(int columnIndex)
TimeColumn	timeColumn(String columnName)
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

Relation

public Relation()

Method Detail

addColumn

public abstract Relation addColumn(Column... cols)

setName

public abstract Relation setName(String name)

isEmpty

public boolean isEmpty()

shape

public String shape()

removeColumn

public Relation removeColumn(int columnIndex)

removeColumns

public abstract Relation removeColumns(Column... columns)

Removes the given columns from the receiver

removeColumns

public Relation removeColumns(String... columnName)

first

public abstract Table first(int nRows)

columnIndex

public int columnIndex(String columnName)

Returns the index of the column with the given columnName

column

public Column column(String columnName)

Returns the column with the given columnName, ignoring case

column

public abstract Column column(int columnIndex)

Returns the column at columnIndex (0-based)

Parameters:

columnIndex - an integer at least 0 and less than number of columns in the relation

Returns:

the column at the given index

columnCount

public abstract int columnCount()

Returns the number of columns in the relation

rowCount

public abstract int rowCount()

Returns the number of rows in the relation

columns

public abstract List<Column> columns()

Returns a list of all the columns in the relation

columnIndex

public abstract int columnIndex(Column col)

Returns the index of the given column

get

public abstract String get(int r,
                           int c)

Returns a String representing the value found at column index c and row index r

name

public abstract String name()

Returns the name of this relation

clear

public abstract void clear()

Clears all the dat in the relation, leaving the structure intact

columnNames

public abstract List<String> columnNames()

columnTypes

public ColumnType[] columnTypes()

Returns an array of the column types of all columns in the relation, including duplicates as appropriate, and maintaining order

colWidths

public int[] colWidths()

Returns an array of column widths for printing tables

toString

public String toString()

Overrides:

toString in class Object

print

public String print(int rowLimit)

print

public String print()

structure

public Table structure()

summary

public String summary()

booleanColumn

public BooleanColumn booleanColumn(int columnIndex)

booleanColumn

public BooleanColumn booleanColumn(String columnName)

numericColumn

public NumericColumn numericColumn(int columnIndex)

numericColumn

public NumericColumn numericColumn(String columnName)

nCol

public NumericColumn nCol(String columnName)

Returns the column with the given name cast to a NumericColumn

Shorthand for numericColumn()

nCol

public NumericColumn nCol(int columnIndex)

Returns the column with the given name cast to a NumericColumn

Shorthand for numericColumn()

floatColumn

public FloatColumn floatColumn(int columnIndex)

floatColumn

public FloatColumn floatColumn(String columnName)

doubleColumn

public DoubleColumn doubleColumn(int columnIndex)

doubleColumn

public DoubleColumn doubleColumn(String columnName)

intColumn

public IntColumn intColumn(String columnName)

intColumn

public IntColumn intColumn(int columnIndex)

shortColumn

public ShortColumn shortColumn(String columnName)

shortColumn

public ShortColumn shortColumn(int columnIndex)

longColumn

public LongColumn longColumn(String columnName)

longColumn

public LongColumn longColumn(int columnIndex)

dateColumn

public DateColumn dateColumn(int columnIndex)

dateColumn

public DateColumn dateColumn(String columnName)

timeColumn

public TimeColumn timeColumn(String columnName)

timeColumn

public TimeColumn timeColumn(int columnIndex)

categoryColumn

public CategoryColumn categoryColumn(String columnName)

categoryColumn

public CategoryColumn categoryColumn(int columnIndex)

dateTimeColumn

public DateTimeColumn dateTimeColumn(int columnIndex)

dateTimeColumn

public DateTimeColumn dateTimeColumn(String columnName)