Table (tablesaw-core 0.41.0 API)

java.lang.Object
- tech.tablesaw.table.Relation
- - tech.tablesaw.api.Table

All Implemented Interfaces:

Iterable<Row>
```
public class Table
extends Relation
implements Iterable<Row>
```
A table of data, consisting of some number of columns, each of which has the same number of rows. All the data in a column has the same type: integer, float, category, etc., but a table may contain an arbitrary number of columns of any type.
Tables are the main data-type and primary focus of Tablesaw.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class Table.RowPair
Deprecated.

Nested Classes
Modifier and Type	Class	Description
`static class`	`Table.RowPair`	Deprecated.

Field Summary

Fields
Modifier and Type	Field	Description
`static ReaderRegistry`	`defaultReaderRegistry`
`static WriterRegistry`	`defaultWriterRegistry`
`static String`	`MELT_VALUE_COLUMN_NAME`
`static String`	`MELT_VARIABLE_COLUMN_NAME`

Constructor Summary

Constructors
Modifier	Constructor	Description
`protected`	`Table(String name, Collection<Column<?>> columns)`	Returns a new Table initialized with the given names and columns
`protected`	`Table(String name, Column<?>... columns)`	Returns a new Table initialized with the given names and columns

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`Table`	`addColumns(Column<?>... cols)`	Adds the given column to this table
`void`	`addRow(int rowIndex, Table sourceTable)`	Adds a single row to this table from sourceTable, copying every column in sourceTable
`void`	`addRow(Row row)`	Deprecated. Use `append(Row)` instead.
`Table`	`append(Row row)`	Appends the given row to this table and returns the table.
`Table`	`append(Relation tableToAppend)`	Returns this table after adding the data from the argument
`Row`	`appendRow()`	Appends an empty row and returns a Row object indexed to the newly added row so values can be set.
`Table`	`cast()`	Cast implements the 'tidy' cast operation as described in these papers by Hadley Wickham:
`List<CategoricalColumn<?>>`	`categoricalColumns(String... columnNames)`	Returns only the columns whose names are given in the input array
`void`	`clear()`	Clears all the data from this table
`Column<?>`	`column(int columnIndex)`	Returns the column at the given index in the column list
`Column<?>[]`	`columnArray()`	Returns the columns in this table as an array
`int`	`columnCount()`	Returns the number of columns in the table
`int`	`columnIndex(String columnName)`	Returns the index of the column with the given name
`int`	`columnIndex(Column<?> column)`	Returns the index of the given column (its position in the list of columns)
`List<String>`	`columnNames()`	Returns a List of the names of all the columns in this table
`List<Column<?>>`	`columns()`	Returns the list of columns
`Table`	`concat(Table tableToConcatenate)`	Add all the columns of tableToConcatenate to this table Note: The columns in the result must have unique names, when compared case insensitive Note: Both tables must have the same number of rows
`Table`	`copy()`	Returns a table with the same columns as this table
`Table`	`countBy(String... categoricalColumnNames)`	Returns a table containing a column for each grouping column, and a column named "Count" that contains the counts for each combination of grouping column values
`Table`	`countBy(CategoricalColumn<?>... groupingColumns)`	Returns a table containing two columns, the grouping column, and a column named "Count" that contains the counts for each grouping column value
`static Table`	`create()`	Returns a new, empty table (without rows or columns)
`static Table`	`create(String tableName)`	Returns a new, empty table (without rows or columns) with the given name
`static Table`	`create(String name, Collection<Column<?>> columns)`	Returns a new table with the given columns and given name
`static Table`	`create(String name, Stream<Column<?>> columns)`	Returns a new table with the given columns and given name
`static Table`	`create(String name, Column<?>... columns)`	Returns a new table with the given columns and given name
`static Table`	`create(Collection<Column<?>> columns)`	Returns a new table with the given columns
`static Table`	`create(Stream<Column<?>> columns)`	Returns a new table with the given columns
`static Table`	`create(Column<?>... columns)`	Returns a new table with the given columns
`boolean`	`detect(Predicate<Row> predicate)`	Deprecated. use `stream().anyMatch`
`void`	`doWithRowPairs(Consumer<Table.RowPair> pairConsumer)`	Deprecated. use stream(2).forEach(rowConsumer)
`void`	`doWithRows(Consumer<Row> doable)`	Deprecated. use `stream().forEach`
`void`	`doWithRows(tech.tablesaw.api.Table.Pairs pairs)`	Deprecated. use stream(2).forEach(rowConsumer)
`Table`	`dropDuplicateRows()`	Returns the unique records in this table Note: Uses a lot of memory for a sort
`Table`	`dropRange(int rowCount)`	Returns a new table EXCLUDING the first rowCount rows if rowCount positive.
`Table`	`dropRange(int rowStart, int rowEnd)`	Returns a table EXCLUDING the rows contained in the range from rowStart inclusive to rowEnd exclusive
`Table`	`dropRows(int... rowNumbers)`	Returns a table EXCLUDING the rows contained in the given array of row indices
`Table`	`dropRowsWithMissingValues()`	Returns only those records in this table that have no columns with missing values
`Table`	`dropWhere(Function<Table,Selection> selection)`	Returns a new Table made by EXCLUDING any rows returned when the given function is applied to this table
`Table`	`dropWhere(Selection selection)`	Returns a table EXCLUDING the rows contained in the given Selection
`Table`	`emptyCopy()`	Returns a table with the same columns as this table, but no data
`Table`	`emptyCopy(int rowSize)`	Returns a table with the same columns as this table, but no data, initialized to the given row size
`Table`	`first(int nRows)`	Returns a new table containing the first `nrows` of data in this table
`Table`	`inRange(int rowCount)`	Returns a new table containing the first rowCount rows if rowCount positive.
`Table`	`inRange(int rowStart, int rowEnd)`	Returns a new table containing the rows contained in the range from rowStart inclusive to rowEnd exclusive
`Table`	`insertColumn(int index, Column<?> column)`	Adds the given column to this table at the given position in the column list
`void`	`internalAddWithoutValidation(Column<?> c)`	For internal Tablesaw use only
`Iterator<Row>`	`iterator()`
`DataFrameJoiner`	`joinOn(String... columnNames)`	Returns a new DataFrameJoiner initialized with multiple `columnNames`
`Table`	`last(int nRows)`	Returns a new table containing the last `nrows` of data in this table
`Table`	`melt(List<String> idVariables, List<NumericColumn<?>> measuredVariables, Boolean dropMissing)`	Melt implements the 'tidy' melt operation as described in these papers by Hadley Wickham.
`Table`	`missingValueCounts()`	Returns a table containing the number of missing values in each column in this table
`String`	`name()`	Returns the name of the table
`Table`	`pivot(String column1Name, String column2Name, String column3Name, AggregateFunction<?,?> aggregateFunction)`	Returns a pivot on this table, where: The first column contains unique values from the index column1 There are n additional columns, one for each unique value in column2 The values in each of the cells in these new columns are the result of applying the given AggregateFunction to the data in column3, grouped by the values of column1 and column2
`Table`	`pivot(CategoricalColumn<?> column1, CategoricalColumn<?> column2, NumericColumn<?> column3, AggregateFunction<?,?> aggregateFunction)`	Returns a pivot on this table, where: The first column contains unique values from the index column1 There are n additional columns, one for each unique value in column2 The values in each of the cells in these new columns are the result of applying the given AggregateFunction to the data in column3, grouped by the values of column1 and column2
`static DataFrameReader`	`read()`	Returns an object that an be used to read data from a file into a new Table
`Table`	`rejectColumns(int... columnIndexes)`	Returns a new table containing copies of all the columns from this table, except those at the given indexes
`Table`	`rejectColumns(String... columnNames)`	Returns a new table containing copies of all the columns from this table, except those named in the argument
`Table`	`rejectColumns(Column<?>... columns)`	Returns a new table containing copies of all the columns from this table, except those named in the argument
`Table`	`removeColumns(int... columnIndexes)`	Removes the columns at the given indices from this table and returns this table
`Table`	`removeColumns(String... columns)`	Removes the columns with the given names from this table and returns this table
`Table`	`removeColumns(Column<?>... columns)`	Removes the given columns from this table and returns this table
`Table`	`removeColumnsWithMissingValues()`	Removes all columns with missing values from this table, and returns this table.
`Table`	`reorderColumns(String... columnNames)`	Return a new table (shallow copy) that contains all the columns in this table, in the order given in the argument.
`Table`	`replaceColumn(int colIndex, Column<?> newColumn)`	Replaces an existing column (by index) in this table with the given new column
`Table`	`replaceColumn(String columnName, Column<?> newColumn)`	Replaces an existing column (by name) in this table with the given new column
`Table`	`replaceColumn(Column<?> newColumn)`	Replaces an existing column having the same name of the given column with the given column
`Table`	`retainColumns(int... columnIndexes)`	Removes all columns except for those given in the argument from this table and returns this table
`Table`	`retainColumns(String... columnNames)`	Removes all columns except for those given in the argument from this table and returns this table
`Table`	`retainColumns(Column<?>... columns)`	Removes all columns except for those given in the argument from this table and returns this table
`Iterator<Row[]>`	`rollingIterator(int n)`	Iterates over rolling sets of rows.
`Stream<Row[]>`	`rollingStream(int n)`	Streams over rolling sets of rows.
`void`	`rollWithRows(Consumer<Row[]> rowConsumer, int n)`	Deprecated. use stream(n).forEach(rowConsumer)
`Row`	`row(int rowIndex)`	Returns a new Row object with its position set to the given zero-based row index.
`int`	`rowCount()`	Returns the number of rows in the table
`Table`	`rows(int... rowNumbers)`	Returns a table containing the rows contained in the given array of row indices
`Table`	`sampleN(int nRows)`	Returns a table consisting of randomly selected records from this table
`Table[]`	`sampleSplit(double table1Proportion)`	Splits the table into two, randomly assigning records to each according to the proportion given in trainingProportion
`Table`	`sampleX(double proportion)`	Returns a table consisting of randomly selected records from this table.
`Table`	`select(String... columnNames)`	Deprecated. Use `selectColumns(String[])` instead
`Table`	`select(Column<?>... columns)`	Deprecated. Use `selectColumns(Column[])` instead
`Table`	`selectColumns(int... columnIndexes)`	Returns a new table containing copies of the columns at the given indexes
`Table`	`selectColumns(String... columnNames)`	Returns a new table containing copies of the selected columns from this table
`Table`	`selectColumns(Column<?>... columns)`	Returns a new table containing copies of the selected columns from this table
`Table`	`setName(String name)`	Sets the name of the table
`Table`	`sortAscendingOn(String... columnNames)`	Returns a copy of this table sorted in the order of the given column names, in ascending order
`Table`	`sortDescendingOn(String... columnNames)`	Returns a copy of this table sorted on the given column names, applied in order, descending TODO: Provide equivalent methods naming columns by index
`Table`	`sortOn(int... columnIndexes)`	Sorts this table into a new table on the columns indexed
`Table`	`sortOn(String... columnNames)`	Returns a copy of this table sorted on the given column names, applied in order,
`Table`	`sortOn(Comparator<Row> rowComparator)`	Returns a copy of this table sorted using the given comparator
`Table`	`sortOn(Sort key)`	Returns a copy of this table sorted using the given sort key.
`TableSliceGroup`	`splitOn(String... columns)`	Returns a non-overlapping and exhaustive collection of "slices" over this table.
`TableSliceGroup`	`splitOn(CategoricalColumn<?>... columns)`	Returns a non-overlapping and exhaustive collection of "slices" over this table.
`Iterator<Row[]>`	`steppingIterator(int n)`	Streams over stepped sets of rows.
`Stream<Row[]>`	`steppingStream(int n)`	Streams over stepped sets of rows.
`void`	`stepWithRows(Consumer<Row[]> rowConsumer, int n)`	Deprecated. use steppingStream(n).forEach(rowConsumer)
`Table[]`	`stratifiedSampleSplit(CategoricalColumn<?> column, double table1Proportion)`	Splits the table into two stratified samples, this uses the specified column to divide the table into groups, randomly assigning records to each according to the proportion given in trainingProportion.
`Stream<Row>`	`stream()`	Returns the rows in this table as a Stream
`Summarizer`	`summarize(String col1Name, String col2Name, String col3Name, String col4Name, AggregateFunction<?,?>... functions)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Summarizer`	`summarize(String col1Name, String col2Name, String col3Name, AggregateFunction<?,?>... functions)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Summarizer`	`summarize(String numericColumn1Name, String numericColumn2Name, AggregateFunction<?,?>... functions)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Summarizer`	`summarize(String columName, AggregateFunction<?,?>... functions)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Summarizer`	`summarize(List<String> columnNames, AggregateFunction<?,?>... functions)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Summarizer`	`summarize(Column<?> numberColumn, AggregateFunction<?,?>... function)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Summarizer`	`summarize(Column<?> column1, Column<?> column2, AggregateFunction<?,?>... function)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Summarizer`	`summarize(Column<?> column1, Column<?> column2, Column<?> column3, AggregateFunction<?,?>... function)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Summarizer`	`summarize(Column<?> column1, Column<?> column2, Column<?> column3, Column<?> column4, AggregateFunction<?,?>... function)`	Returns an `Summarizer` that can be used to summarize the column with the given name(s) using the given functions.
`Table`	`transpose()`	Transposes data in the table, switching rows for columns.
`Table`	`transpose(boolean includeColumnHeadingsAsFirstColumn, boolean useFirstColumnForHeadings)`	Transposes data in the table, switching rows for columns.
`Table`	`where(Function<Table,Selection> selection)`	Returns a new Table made by applying the given function to this table
`Table`	`where(Selection selection)`	Returns a table containing the rows contained in the given Selection
`DataFrameWriter`	`write()`	Returns an object that an be used to write data from a Table into a file.
`Table`	`xTabColumnPercents(String column1Name, String column2Name)`	Returns a table with n by m + 1 cells.
`Table`	`xTabCounts(String column1Name)`	Returns a table with two columns, the first contains a value each unique value in the argument, and the second contains the number of observations of each value
`Table`	`xTabCounts(String column1Name, String column2Name)`	Returns a table with n by m + 1 cells.
`Table`	`xTabPercents(String column1Name)`	TODO: Rename the method to xTabProportions, deprecating this version Returns a table with two columns, the first contains a value each unique value in the argument, and the second contains the proportion of observations having that value
`Table`	`xTabRowPercents(String column1Name, String column2Name)`	Returns a table with n by m + 1 cells.
`Table`	`xTabTablePercents(String column1Name, String column2Name)`	Returns a table with n by m + 1 cells.

Methods inherited from interface java.lang.Iterable
forEach, spliterator

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from class tech.tablesaw.table.Relation
as, booleanColumn, booleanColumn, booleanColumns, categoricalColumn, categoricalColumn, column, columns, columns, columnsOfType, columnTypes, colWidths, containsColumn, containsColumn, dateColumn, dateColumn, dateColumns, dateTimeColumn, dateTimeColumn, dateTimeColumns, doubleColumn, doubleColumn, floatColumn, floatColumn, get, getString, getString, getUnformatted, instantColumn, instantColumn, instantColumns, intColumn, intColumn, isEmpty, longColumn, longColumn, nCol, nCol, numberColumn, numberColumn, numberColumns, numericColumns, numericColumns, numericColumns, print, print, printAll, shape, shortColumn, shortColumn, smile, stringColumn, stringColumn, stringColumns, structure, summary, textColumn, textColumn, timeColumn, timeColumn, timeColumns, toString, typeArray, types

- Field Detail
  - defaultReaderRegistry
```
public static final ReaderRegistry defaultReaderRegistry
```
  - defaultWriterRegistry
```
public static final WriterRegistry defaultWriterRegistry
```
  - MELT_VARIABLE_COLUMN_NAME
```
public static final String MELT_VARIABLE_COLUMN_NAME
```
    See Also:
    
    Constant Field Values
  - MELT_VALUE_COLUMN_NAME
```
public static final String MELT_VALUE_COLUMN_NAME
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - Table
```
protected Table(String name,
                Column<?>... columns)
```
    Returns a new Table initialized with the given names and columns
    
    Parameters:
    
    name - The name of the table
    
    columns - One or more columns, all of which must have either the same length or size 0
  - Table
```
protected Table(String name,
                Collection<Column<?>> columns)
```
    Returns a new Table initialized with the given names and columns
    
    Parameters:
    
    name - The name of the table
    
    columns - One or more columns, all of which must have either the same length or size 0
- Method Detail
  - create
```
public static Table create()
```
    Returns a new, empty table (without rows or columns)
  - create
```
public static Table create(String tableName)
```
    Returns a new, empty table (without rows or columns) with the given name
  - create
```
public static Table create(Column<?>... columns)
```
    Returns a new table with the given columns
    
    Parameters:
    
    columns - one or more columns, all of the same @code{column.size()}
  - create
```
public static Table create(Collection<Column<?>> columns)
```
    Returns a new table with the given columns
    
    Parameters:
    
    columns - one or more columns, all of the same @code{column.size()}
  - create
```
public static Table create(Stream<Column<?>> columns)
```
    Returns a new table with the given columns
    
    Parameters:
    
    columns - one or more columns, all of the same @code{column.size()}
  - create
```
public static Table create(String name,
                           Column<?>... columns)
```
    Returns a new table with the given columns and given name
    
    Parameters:
    
    name - the name for this table
    
    columns - one or more columns, all of the same @code{column.size()}
  - create
```
public static Table create(String name,
                           Collection<Column<?>> columns)
```
    Returns a new table with the given columns and given name
    
    Parameters:
    
    name - the name for this table
    
    columns - one or more columns, all of the same @code{column.size()}
  - create
```
public static Table create(String name,
                           Stream<Column<?>> columns)
```
    Returns a new table with the given columns and given name
    
    Parameters:
    
    name - the name for this table
    
    columns - one or more columns, all of the same @code{column.size()}
  - read
```
public static DataFrameReader read()
```
    Returns an object that an be used to read data from a file into a new Table
  - write
```
public DataFrameWriter write()
```
    Returns an object that an be used to write data from a Table into a file. If the file exists, it is over-written
  - addColumns
```
public Table addColumns(Column<?>... cols)
```
    Adds the given column to this table
    
    Specified by:
    
    addColumns in class Relation
    
    Returns:
    
    This Relation
  - internalAddWithoutValidation
```
public void internalAddWithoutValidation(Column<?> c)
```
    For internal Tablesaw use only
    Adds the given column to this table without performing duplicate-name or column size checks
  - insertColumn
```
public Table insertColumn(int index,
                          Column<?> column)
```
    Adds the given column to this table at the given position in the column list
    
    Parameters:
    
    index - Zero-based index into the column list
    
    column - Column to be added
  - reorderColumns
```
public Table reorderColumns(String... columnNames)
```
    Return a new table (shallow copy) that contains all the columns in this table, in the order given in the argument. Throw an IllegalArgument exception if the number of names given does not match the number of columns in this table. NOTE: This does not make a copy of the columns, so they are shared between the two tables.
    
    Parameters:
    
    columnNames - a column name or array of names
  - replaceColumn
```
public Table replaceColumn(int colIndex,
                           Column<?> newColumn)
```
    Replaces an existing column (by index) in this table with the given new column
    
    Parameters:
    
    colIndex - Zero-based index of the column to be replaced
    
    newColumn - Column to be added
  - replaceColumn
```
public Table replaceColumn(String columnName,
                           Column<?> newColumn)
```
    Replaces an existing column (by name) in this table with the given new column
    
    Parameters:
    
    columnName - String name of the column to be replaced
    
    newColumn - Column to be added
  - replaceColumn
```
public Table replaceColumn(Column<?> newColumn)
```
    Replaces an existing column having the same name of the given column with the given column
    
    Parameters:
    
    newColumn - Column to be added
  - setName
```
public Table setName(String name)
```
    Sets the name of the table
    
    Specified by:
    
    setName in class Relation
    
    Returns:
    
    This Relation
  - column
```
public Column<?> column(int columnIndex)
```
    Returns the column at the given index in the column list
    
    Specified by:
    
    column in class Relation
    
    Parameters:
    
    columnIndex - an integer at least 0 and less than number of columns in the table
    
    Returns:
    
    the column at the given index
  - columnCount
```
public int columnCount()
```
    Returns the number of columns in the table
    
    Specified by:
    
    columnCount in class Relation
  - rowCount
```
public int rowCount()
```
    Returns the number of rows in the table
    
    Specified by:
    
    rowCount in class Relation
  - columns
```
public List<Column<?>> columns()
```
    Returns the list of columns
    
    Specified by:
    
    columns in class Relation
  - columnArray
```
public Column<?>[] columnArray()
```
    Returns the columns in this table as an array
  - categoricalColumns
```
public List<CategoricalColumn<?>> categoricalColumns(String... columnNames)
```
    Returns only the columns whose names are given in the input array
    
    Overrides:
    
    categoricalColumns in class Relation
  - columnIndex
```
public int columnIndex(String columnName)
```
    Returns the index of the column with the given name
    
    Overrides:
    
    columnIndex in class Relation
    
    Throws:
    
    IllegalArgumentException - if the input string is not the name of any column in the table
  - columnIndex
```
public int columnIndex(Column<?> column)
```
    Returns the index of the given column (its position in the list of columns)
    
    Specified by:
    
    columnIndex in class Relation
    
    Throws:
    
    IllegalArgumentException - if the column is not present in this table
  - name
```
public String name()
```
    Returns the name of the table
    
    Specified by:
    
    name in class Relation
  - columnNames
```
public List<String> columnNames()
```
    Returns a List of the names of all the columns in this table
    
    Specified by:
    
    columnNames in class Relation
  - copy
```
public Table copy()
```
    Returns a table with the same columns as this table
  - emptyCopy
```
public Table emptyCopy()
```
    Returns a table with the same columns as this table, but no data
  - emptyCopy
```
public Table emptyCopy(int rowSize)
```
    Returns a table with the same columns as this table, but no data, initialized to the given row size
  - sampleSplit
```
public Table[] sampleSplit(double table1Proportion)
```
    Splits the table into two, randomly assigning records to each according to the proportion given in trainingProportion
    
    Parameters:
    
    table1Proportion - The proportion to go in the first table
    
    Returns:
    
    An array two tables, with the first table having the proportion specified in the method parameter, and the second table having the balance of the rows
  - stratifiedSampleSplit
```
public Table[] stratifiedSampleSplit(CategoricalColumn<?> column,
                                     double table1Proportion)
```
    Splits the table into two stratified samples, this uses the specified column to divide the table into groups, randomly assigning records to each according to the proportion given in trainingProportion.
    
    Parameters:
    
    column - the column to be used for the stratified sampling
    
    table1Proportion - The proportion to go in the first table
    
    Returns:
    
    An array two tables, with the first table having the proportion specified in the method parameter, and the second table having the balance of the rows
  - sampleX
```
public Table sampleX(double proportion)
```
    Returns a table consisting of randomly selected records from this table. The sample size is based on the given proportion
    
    Parameters:
    
    proportion - The proportion to go in the sample
  - sampleN
```
public Table sampleN(int nRows)
```
    Returns a table consisting of randomly selected records from this table
    
    Parameters:
    
    nRows - The number of rows to go in the sample
  - clear
```
public void clear()
```
    Clears all the data from this table
    
    Specified by:
    
    clear in class Relation
  - first
```
public Table first(int nRows)
```
    Returns a new table containing the first nrows of data in this table
    
    Specified by:
    
    first in class Relation
  - last
```
public Table last(int nRows)
```
    Returns a new table containing the last nrows of data in this table
  - sortOn
```
public Table sortOn(int... columnIndexes)
```
    Sorts this table into a new table on the columns indexed
    if index is negative then sort that column in descending order otherwise sort ascending
  - sortOn
```
public Table sortOn(String... columnNames)
```
    Returns a copy of this table sorted on the given column names, applied in order,
    if column name starts with - then sort that column descending otherwise sort ascending
  - sortAscendingOn
```
public Table sortAscendingOn(String... columnNames)
```
    Returns a copy of this table sorted in the order of the given column names, in ascending order
  - sortDescendingOn
```
public Table sortDescendingOn(String... columnNames)
```
    Returns a copy of this table sorted on the given column names, applied in order, descending TODO: Provide equivalent methods naming columns by index
  - sortOn
```
public Table sortOn(Sort key)
```
    Returns a copy of this table sorted using the given sort key.
    
    Parameters:
    
    key - to sort on.
    
    Returns:
    
    a sorted copy of this table.
  - sortOn
```
public Table sortOn(Comparator<Row> rowComparator)
```
    Returns a copy of this table sorted using the given comparator
  - addRow
```
public void addRow(int rowIndex,
                   Table sourceTable)
```
    Adds a single row to this table from sourceTable, copying every column in sourceTable
    
    Parameters:
    
    rowIndex - The row in sourceTable to add to this table
    
    sourceTable - A table with the same column structure as this table
  - addRow
```
@Deprecated
public void addRow(Row row)
```
    Deprecated. Use append(Row) instead.
    
    Adds the given row to this table
  - row
```
public Row row(int rowIndex)
```
    Returns a new Row object with its position set to the given zero-based row index.
  - rows
```
public Table rows(int... rowNumbers)
```
    Returns a table containing the rows contained in the given array of row indices
  - dropRows
```
public Table dropRows(int... rowNumbers)
```
    Returns a table EXCLUDING the rows contained in the given array of row indices
  - inRange
```
public Table inRange(int rowCount)
```
    Returns a new table containing the first rowCount rows if rowCount positive. Returns the last rowCount rows if rowCount negative.
  - inRange
```
public Table inRange(int rowStart,
                     int rowEnd)
```
    Returns a new table containing the rows contained in the range from rowStart inclusive to rowEnd exclusive
  - dropRange
```
public Table dropRange(int rowCount)
```
    Returns a new table EXCLUDING the first rowCount rows if rowCount positive. Drops the last rowCount rows if rowCount negative.
  - dropRange
```
public Table dropRange(int rowStart,
                       int rowEnd)
```
    Returns a table EXCLUDING the rows contained in the range from rowStart inclusive to rowEnd exclusive
  - where
```
public Table where(Selection selection)
```
    Returns a table containing the rows contained in the given Selection
  - where
```
public Table where(Function<Table,Selection> selection)
```
    Returns a new Table made by applying the given function to this table
  - dropWhere
```
public Table dropWhere(Function<Table,Selection> selection)
```
    Returns a new Table made by EXCLUDING any rows returned when the given function is applied to this table
  - dropWhere
```
public Table dropWhere(Selection selection)
```
    Returns a table EXCLUDING the rows contained in the given Selection
  - pivot
```
public Table pivot(CategoricalColumn<?> column1,
                   CategoricalColumn<?> column2,
                   NumericColumn<?> column3,
                   AggregateFunction<?,?> aggregateFunction)
```
    Returns a pivot on this table, where: The first column contains unique values from the index column1 There are n additional columns, one for each unique value in column2 The values in each of the cells in these new columns are the result of applying the given AggregateFunction to the data in column3, grouped by the values of column1 and column2
  - pivot
```
public Table pivot(String column1Name,
                   String column2Name,
                   String column3Name,
                   AggregateFunction<?,?> aggregateFunction)
```
    Returns a pivot on this table, where: The first column contains unique values from the index column1 There are n additional columns, one for each unique value in column2 The values in each of the cells in these new columns are the result of applying the given AggregateFunction to the data in column3, grouped by the values of column1 and column2
  - splitOn
```
public TableSliceGroup splitOn(String... columns)
```
    Returns a non-overlapping and exhaustive collection of "slices" over this table. Each slice is like a virtual table containing a subset of the records in this table
    This method is intended for advanced or unusual operations on the subtables. If you want to calculate summary statistics for each subtable, the summarize methods (e.g)
    table.summarize(myColumn, mean, median).by(columns)
    are preferred
  - splitOn
```
public TableSliceGroup splitOn(CategoricalColumn<?>... columns)
```
    Returns a non-overlapping and exhaustive collection of "slices" over this table. Each slice is like a virtual table containing a subset of the records in this table
    This method is intended for advanced or unusual operations on the subtables. If you want to calculate summary statistics for each subtable, the summarize methods (e.g)
    table.summarize(myColumn, mean, median).by(columns)
    are preferred
  - dropDuplicateRows
```
public Table dropDuplicateRows()
```
    Returns the unique records in this table Note: Uses a lot of memory for a sort
  - dropRowsWithMissingValues
```
public Table dropRowsWithMissingValues()
```
    Returns only those records in this table that have no columns with missing values
  - selectColumns
```
public Table selectColumns(Column<?>... columns)
```
    Returns a new table containing copies of the selected columns from this table
    
    Parameters:
    
    columns - The columns to copy into the new table
    
    See Also:
    
    retainColumns(Column[])
  - select
```
public Table select(Column<?>... columns)
```
    Deprecated. Use selectColumns(Column[]) instead
    
    Returns a new table containing copies of the selected columns from this table
    
    Parameters:
    
    columns - The columns to copy into the new table
    
    See Also:
    
    retainColumns(Column[])
  - selectColumns
```
public Table selectColumns(String... columnNames)
```
    Returns a new table containing copies of the selected columns from this table
    
    Parameters:
    
    columnNames - The names of the columns to include
    
    See Also:
    
    retainColumns(String[])
  - select
```
public Table select(String... columnNames)
```
    Deprecated. Use selectColumns(String[]) instead
    
    Returns a new table containing copies of the selected columns from this table
    
    Parameters:
    
    columnNames - The names of the columns to include
    
    See Also:
    
    retainColumns(String[])
  - rejectColumns
```
public Table rejectColumns(int... columnIndexes)
```
    Returns a new table containing copies of all the columns from this table, except those at the given indexes
    
    Parameters:
    
    columnIndexes - The indexes of the columns to exclude
    
    See Also:
    
    removeColumns(int[])
  - rejectColumns
```
public Table rejectColumns(String... columnNames)
```
    Returns a new table containing copies of all the columns from this table, except those named in the argument
    
    Parameters:
    
    columnNames - The names of the columns to exclude
    
    See Also:
    
    removeColumns(int[])
  - rejectColumns
```
public Table rejectColumns(Column<?>... columns)
```
    Returns a new table containing copies of all the columns from this table, except those named in the argument
    
    Parameters:
    
    columns - The names of the columns to exclude
    
    See Also:
    
    removeColumns(int[])
  - selectColumns
```
public Table selectColumns(int... columnIndexes)
```
    Returns a new table containing copies of the columns at the given indexes
    
    Parameters:
    
    columnIndexes - The indexes of the columns to include
    
    See Also:
    
    retainColumns(int[])
  - removeColumns
```
public Table removeColumns(Column<?>... columns)
```
    Removes the given columns from this table and returns this table
    
    Specified by:
    
    removeColumns in class Relation
    
    Returns:
    
    This Relation
  - removeColumnsWithMissingValues
```
public Table removeColumnsWithMissingValues()
```
    Removes all columns with missing values from this table, and returns this table.
  - retainColumns
```
public Table retainColumns(Column<?>... columns)
```
    Removes all columns except for those given in the argument from this table and returns this table
  - retainColumns
```
public Table retainColumns(int... columnIndexes)
```
    Removes all columns except for those given in the argument from this table and returns this table
  - retainColumns
```
public Table retainColumns(String... columnNames)
```
    Removes all columns except for those given in the argument from this table and returns this table
  - append
```
public Table append(Relation tableToAppend)
```
    Returns this table after adding the data from the argument
  - append
```
public Table append(Row row)
```
    Appends the given row to this table and returns the table.
    Note: The table is modified in-place TODO: Performance
  - removeColumns
```
public Table removeColumns(String... columns)
```
    Removes the columns with the given names from this table and returns this table
    
    Overrides:
    
    removeColumns in class Relation
    
    Returns:
    
    This Relation
  - removeColumns
```
public Table removeColumns(int... columnIndexes)
```
    Removes the columns at the given indices from this table and returns this table
    
    Overrides:
    
    removeColumns in class Relation
    
    Returns:
    
    This Relation
  - appendRow
```
public Row appendRow()
```
    Appends an empty row and returns a Row object indexed to the newly added row so values can be set.
    Intended usage:
    for (int i = 0; ...) { Row row = table.appendRow(); row.setString("name", "Bob"); row.setFloat("IQ", 123.4f); ...etc. }
  - concat
```
public Table concat(Table tableToConcatenate)
```
    Add all the columns of tableToConcatenate to this table Note: The columns in the result must have unique names, when compared case insensitive Note: Both tables must have the same number of rows
    
    Parameters:
    
    tableToConcatenate - The table containing the columns to be added
    
    Returns:
    
    This table
  - summarize
```
public Summarizer summarize(String columName,
                            AggregateFunction<?,?>... functions)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - summarize
```
public Summarizer summarize(List<String> columnNames,
                            AggregateFunction<?,?>... functions)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - summarize
```
public Summarizer summarize(String numericColumn1Name,
                            String numericColumn2Name,
                            AggregateFunction<?,?>... functions)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - summarize
```
public Summarizer summarize(String col1Name,
                            String col2Name,
                            String col3Name,
                            AggregateFunction<?,?>... functions)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - summarize
```
public Summarizer summarize(String col1Name,
                            String col2Name,
                            String col3Name,
                            String col4Name,
                            AggregateFunction<?,?>... functions)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - summarize
```
public Summarizer summarize(Column<?> numberColumn,
                            AggregateFunction<?,?>... function)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - summarize
```
public Summarizer summarize(Column<?> column1,
                            Column<?> column2,
                            AggregateFunction<?,?>... function)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - summarize
```
public Summarizer summarize(Column<?> column1,
                            Column<?> column2,
                            Column<?> column3,
                            AggregateFunction<?,?>... function)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - summarize
```
public Summarizer summarize(Column<?> column1,
                            Column<?> column2,
                            Column<?> column3,
                            Column<?> column4,
                            AggregateFunction<?,?>... function)
```
    Returns an Summarizer that can be used to summarize the column with the given name(s) using the given functions. This object implements reduce/aggregation operations on a table.
    Summarizer can return the results as a table using the Summarizer:apply() method. Summarizer can compute sub-totals using the Summarizer:by() method.
  - xTabCounts
```
public Table xTabCounts(String column1Name,
                        String column2Name)
```
    Returns a table with n by m + 1 cells. The first column contains labels, the other cells contains the counts for every unique combination of values from the two specified columns in this table.
  - xTabRowPercents
```
public Table xTabRowPercents(String column1Name,
                             String column2Name)
```
    Returns a table with n by m + 1 cells. The first column contains labels, the other cells contains the row percents for every unique combination of values from the two specified columns in this table. Row percents total to 100% in every row.
  - xTabColumnPercents
```
public Table xTabColumnPercents(String column1Name,
                                String column2Name)
```
    Returns a table with n by m + 1 cells. The first column contains labels, the other cells contains the column percents for every unique combination of values from the two specified columns in this table. Column percents total to 100% in every column.
  - xTabTablePercents
```
public Table xTabTablePercents(String column1Name,
                               String column2Name)
```
    Returns a table with n by m + 1 cells. The first column contains labels, the other cells contains the proportion for a unique combination of values from the two specified columns in this table
  - xTabPercents
```
public Table xTabPercents(String column1Name)
```
    TODO: Rename the method to xTabProportions, deprecating this version Returns a table with two columns, the first contains a value each unique value in the argument, and the second contains the proportion of observations having that value
  - xTabCounts
```
public Table xTabCounts(String column1Name)
```
    Returns a table with two columns, the first contains a value each unique value in the argument, and the second contains the number of observations of each value
  - countBy
```
public Table countBy(CategoricalColumn<?>... groupingColumns)
```
    Returns a table containing two columns, the grouping column, and a column named "Count" that contains the counts for each grouping column value
  - countBy
```
public Table countBy(String... categoricalColumnNames)
```
    Returns a table containing a column for each grouping column, and a column named "Count" that contains the counts for each combination of grouping column values
    
    Parameters:
    
    categoricalColumnNames - The name(s) of one or more CategoricalColumns in this table
    
    Returns:
    
    A table containing counts of rows grouped by the categorical columns
    
    Throws:
    
    ClassCastException - if the categoricalColumnName parameter is the name of a column that does not * implement categorical
  - joinOn
```
public DataFrameJoiner joinOn(String... columnNames)
```
    Returns a new DataFrameJoiner initialized with multiple columnNames
    
    Parameters:
    
    columnNames - Name of the columns to join on.
    
    Returns:
    
    The new DataFrameJoiner
  - missingValueCounts
```
public Table missingValueCounts()
```
    Returns a table containing the number of missing values in each column in this table
  - iterator
```
public Iterator<Row> iterator()
```
    Specified by:
    
    iterator in interface Iterable<Row>
  - rollingIterator
```
public Iterator<Row[]> rollingIterator(int n)
```
    Iterates over rolling sets of rows. I.e. 0 to n-1, 1 to n, 2 to n+1, etc.
    
    Parameters:
    
    n - the number of rows to return for each iteration
  - steppingIterator
```
public Iterator<Row[]> steppingIterator(int n)
```
    Streams over stepped sets of rows. I.e. 0 to n-1, n to 2n-1, 2n to 3n-1, etc. Only returns full sets of rows.
    
    Parameters:
    
    n - the number of rows to return for each iteration
  - stream
```
public Stream<Row> stream()
```
    Returns the rows in this table as a Stream
  - steppingStream
```
public Stream<Row[]> steppingStream(int n)
```
    Streams over stepped sets of rows. I.e. 0 to n-1, n to 2n-1, 2n to 3n-1, etc. Only returns full sets of rows.
    
    Parameters:
    
    n - the number of rows to return for each iteration
  - rollingStream
```
public Stream<Row[]> rollingStream(int n)
```
    Streams over rolling sets of rows. I.e. 0 to n-1, 1 to n, 2 to n+1, etc.
    
    Parameters:
    
    n - the number of rows to return for each iteration
  - transpose
```
public Table transpose()
```
    Transposes data in the table, switching rows for columns. For example, a table like this.
    value1 | value2 |
    -------------------------------
    1 | 2 |
    1.1 | 2.1 |
    1.2 | 2.2 |
    
    Is transposed into the following
    0 | 1 | 2 |
    -------------------------------------
    1 | 1.1 | 1.2 |
    2 | 2.1 | 2.2 |
    
    Returns:
    
    transposed table
    
    See Also:
    
    transpose(boolean,boolean)
  - transpose
```
public Table transpose(boolean includeColumnHeadingsAsFirstColumn,
                       boolean useFirstColumnForHeadings)
```
    Transposes data in the table, switching rows for columns. For example, a table like this.
    label | value1 | value2 |
    -------------------------------
    row1 | 1 | 2 |
    row2 | 1.1 | 2.1 |
    row3 | 1.2 | 2.2 |
    
    Is transposed into the following
    label | row1 | row2 | row3 |
    -------------------------------------
    value1 | 1 | 1.1 | 1.2 |
    value2 | 2 | 2.1 | 2.2 |
    
    Parameters:
    
    includeColumnHeadingsAsFirstColumn - Toggle whether to include the column headings as first column in result
    
    useFirstColumnForHeadings - Use the first column as the column headings in the result. Useful if the data set already has a first column which contains a set of labels
    
    Returns:
    
    The transposed table
  - melt
```
public Table melt(List<String> idVariables,
                  List<NumericColumn<?>> measuredVariables,
                  Boolean dropMissing)
```
    Melt implements the 'tidy' melt operation as described in these papers by Hadley Wickham.
    Tidy concepts: {@see https://www.jstatsoft.org/article/view/v059i10}
    Cast function details: {@see https://www.jstatsoft.org/article/view/v021i12}
    In short, melt turns columns into rows, but in a particular way. Used with the cast method, it can help make data tidy. In a tidy dataset, every variable is a column and every observation a row.
    This method returns a table that contains all the data in this table, but organized such that there is a set of identifier variables (columns) and a single measured variable (column). For example, given a table with columns:
    patient_id, gender, age, weight, temperature,
    it returns a table with the columns:
    patient_id, variable, value
    In the new format, the strings age, weight, and temperature have become cells in the measurement table, such that a single row in the source table might look like this in the result table:
    1234, gender, male 1234, age, 42 1234, weight, 186 1234, temperature, 97.4
    This kind of structure often makes for a good intermediate format for performing subsequent transformations. It is especially useful when combined with the cast() operation
    
    Parameters:
    
    idVariables - A list of column names intended to be used as identifiers. In he example, only patient_id would be an identifier
    
    measuredVariables - A list of columns intended to be used as measured variables. All columns must have the same type
    
    dropMissing - drop any row where the value is missing
  - cast
```
public Table cast()
```
    Cast implements the 'tidy' cast operation as described in these papers by Hadley Wickham:
    Cast takes a table in 'molten' format, such as is produced by the melt(List, List, Boolean) t} method, and returns a version in standard tidy format.
    The molten table should have a StringColumn called "variable" and a column called "value" Every unique variable name will become a column in the output table.
    All other columns in this table are considered identifier variable. Each combination of identifier variables specifies an observation, so there will be one row for each, with the other variables added.
    Variable columns are returned in an arbitrary order. Use reorderColumns(String...) if column order is important.
    Tidy concepts: {@see https://www.jstatsoft.org/article/view/v059i10}
    Cast function details: {@see https://www.jstatsoft.org/article/view/v021i12}
  - doWithRows
```
@Deprecated
public void doWithRows(Consumer<Row> doable)
```
    Deprecated. use stream().forEach
    
    Applies the operation in doable to every row in the table
  - detect
```
@Deprecated
public boolean detect(Predicate<Row> predicate)
```
    Deprecated. use stream().anyMatch
    
    Applies the predicate to each row, and return true if any row returns true
  - stepWithRows
```
@Deprecated
public void stepWithRows(Consumer<Row[]> rowConsumer,
                         int n)
```
    Deprecated. use steppingStream(n).forEach(rowConsumer)
  - doWithRows
```
@Deprecated
public void doWithRows(tech.tablesaw.api.Table.Pairs pairs)
```
    Deprecated. use stream(2).forEach(rowConsumer)
  - doWithRowPairs
```
@Deprecated
public void doWithRowPairs(Consumer<Table.RowPair> pairConsumer)
```
    Deprecated. use stream(2).forEach(rowConsumer)
  - rollWithRows
```
@Deprecated
public void rollWithRows(Consumer<Row[]> rowConsumer,
                         int n)
```
    Deprecated. use stream(n).forEach(rowConsumer)

Class Table

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from interface java.lang.Iterable

Methods inherited from class java.lang.Object

Methods inherited from class tech.tablesaw.table.Relation

Field Detail

defaultReaderRegistry

defaultWriterRegistry

MELT_VARIABLE_COLUMN_NAME

MELT_VALUE_COLUMN_NAME

Constructor Detail

Table

Table

Method Detail

create

create

create

create

create

create

create

create

read

write

addColumns

internalAddWithoutValidation

insertColumn

reorderColumns

replaceColumn

replaceColumn

replaceColumn

setName

column

columnCount

rowCount

columns

columnArray

categoricalColumns

columnIndex

columnIndex

name

columnNames

copy

emptyCopy

emptyCopy

sampleSplit

stratifiedSampleSplit

sampleX

sampleN

clear

first

last

sortOn

sortOn

sortAscendingOn

sortDescendingOn

sortOn

sortOn

addRow

addRow

row

rows

dropRows

inRange

inRange

dropRange

dropRange

where

where

dropWhere

dropWhere

pivot

pivot

splitOn

splitOn

dropDuplicateRows

dropRowsWithMissingValues