DataFrame

All Superinterfaces:

Dataset<Tuple>, java.lang.Iterable<BaseVector>

All Known Implementing Classes:

IndexDataFrame
```
public interface DataFrame
extends Dataset<Tuple>, java.lang.Iterable<BaseVector>
```
An immutable collection of data organized into named columns.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Default Methods
Modifier and Type	Method and Description
`default BaseVector`	`apply(java.lang.Enum<?> e)` Selects column using an enum value.
`default BaseVector`	`apply(java.lang.String colName)` Selects column based on the column name and return it as a Column.
`default BooleanVector`	`booleanVector(java.lang.Enum<?> e)` Selects column using an enum value.
`BooleanVector`	`booleanVector(int i)` Selects column based on the column index.
`default BooleanVector`	`booleanVector(java.lang.String colName)` Selects column based on the column name.
`default ByteVector`	`byteVector(java.lang.Enum<?> e)` Selects column using an enum value.
`ByteVector`	`byteVector(int i)` Selects column based on the column index.
`default ByteVector`	`byteVector(java.lang.String colName)` Selects column based on the column name.
`default CharVector`	`charVector(java.lang.Enum<?> e)` Selects column using an enum value.
`CharVector`	`charVector(int i)` Selects column based on the column index.
`default CharVector`	`charVector(java.lang.String colName)` Selects column based on the column name.
`static java.util.stream.Collector<Tuple,java.util.List<Tuple>,DataFrame>`	`collect()` Returns a stream collector that accumulates tuples into a DataFrame.
`static <T> java.util.stream.Collector<T,java.util.List<T>,DataFrame>`	`collect(java.lang.Class<T> clazz)` Returns a stream collector that accumulates objects into a DataFrame.
`default BaseVector`	`column(java.lang.Enum<?> e)` Selects column using an enum value.
`BaseVector`	`column(int i)` Selects column based on the column index.
`default BaseVector`	`column(java.lang.String colName)` Selects column based on the column name.
`int`	`columnIndex(java.lang.String name)` Returns the index of a given column name.
`default DoubleVector`	`doubleVector(java.lang.Enum<?> e)` Selects column using an enum value.
`DoubleVector`	`doubleVector(int i)` Selects column based on the column index.
`default DoubleVector`	`doubleVector(java.lang.String colName)` Selects column based on the column name.
`DataFrame`	`drop(int... cols)` Returns a new DataFrame without given column indices.
`default DataFrame`	`drop(java.lang.String... cols)` Returns a new DataFrame without given column names.
`default DataFrame`	`factorize(java.lang.String... cols)` Returns a new DataFrame with given columns converted to nominal.
`default FloatVector`	`floatVector(java.lang.Enum<?> e)` Selects column using an enum value.
`FloatVector`	`floatVector(int i)` Selects column based on the column index.
`default FloatVector`	`floatVector(java.lang.String colName)` Selects column based on the column name.
`default java.lang.Object`	`get(int i, int j)` Returns the cell at (i, j).
`default java.lang.Object`	`get(int i, java.lang.String field)` Returns the cell at (i, j).
`default <T> T[]`	`getArray(int i, int j)` Returns the value at position (i, j) of array type.
`default <T> T[]`	`getArray(int i, java.lang.String field)` Returns the field value of array type.
`default boolean`	`getBoolean(int i, int j)` Returns the value at position (i, j) as a primitive boolean.
`default boolean`	`getBoolean(int i, java.lang.String field)` Returns the field value as a primitive boolean.
`default byte`	`getByte(int i, int j)` Returns the value at position (i, j) as a primitive byte.
`default byte`	`getByte(int i, java.lang.String field)` Returns the field value as a primitive byte.
`default char`	`getChar(int i, int j)` Returns the value at position (i, j) as a primitive byte.
`default char`	`getChar(int i, java.lang.String field)` Returns the field value as a primitive byte.
`default java.time.LocalDate`	`getDate(int i, int j)` Returns the value at position (i, j) of date type as java.time.LocalDate.
`default java.time.LocalDate`	`getDate(int i, java.lang.String field)` Returns the field value of date type as java.time.LocalDate.
`default java.time.LocalDateTime`	`getDateTime(int i, int j)` Returns the value at position (i, j) as java.time.LocalDateTime.
`default java.time.LocalDateTime`	`getDateTime(int i, java.lang.String field)` Returns the field value as java.time.LocalDateTime.
`default java.math.BigDecimal`	`getDecimal(int i, int j)` Returns the value at position (i, j) of decimal type as java.math.BigDecimal.
`default java.math.BigDecimal`	`getDecimal(int i, java.lang.String field)` Returns the field value of decimal type as java.math.BigDecimal.
`default double`	`getDouble(int i, int j)` Returns the value at position (i, j) as a primitive double.
`default double`	`getDouble(int i, java.lang.String field)` Returns the field value as a primitive double.
`default float`	`getFloat(int i, int j)` Returns the value at position (i, j) as a primitive float.
`default float`	`getFloat(int i, java.lang.String field)` Returns the field value as a primitive float.
`default int`	`getInt(int i, int j)` Returns the value at position (i, j) as a primitive int.
`default int`	`getInt(int i, java.lang.String field)` Returns the field value as a primitive int.
`default long`	`getLong(int i, int j)` Returns the value at position (i, j) as a primitive long.
`default long`	`getLong(int i, java.lang.String field)` Returns the field value as a primitive long.
`default java.lang.String`	`getScale(int i, int j)` Returns the value at position (i, j) of NominalScale or OrdinalScale.
`default java.lang.String`	`getScale(int i, java.lang.String field)` Returns the field value of NominalScale or OrdinalScale.
`default short`	`getShort(int i, int j)` Returns the value at position (i, j) as a primitive short.
`default short`	`getShort(int i, java.lang.String field)` Returns the field value as a primitive short.
`default java.lang.String`	`getString(int i, int j)` Returns the value at position (i, j) as a String object.
`default java.lang.String`	`getString(int i, java.lang.String field)` Returns the field value as a String object.
`default Tuple`	`getStruct(int i, int j)` Returns the value at position (i, j) of struct type.
`default Tuple`	`getStruct(int i, java.lang.String field)` Returns the field value of struct type.
`default java.time.LocalTime`	`getTime(int i, int j)` Returns the value at position (i, j) of date type as java.time.LocalTime.
`default java.time.LocalTime`	`getTime(int i, java.lang.String field)` Returns the field value of date type as java.time.LocalTime.
`default IntVector`	`intVector(java.lang.Enum<?> e)` Selects column using an enum value.
`IntVector`	`intVector(int i)` Selects column based on the column index.
`default IntVector`	`intVector(java.lang.String colName)` Selects column based on the column name.
`default boolean`	`isNullAt(int i, int j)` Checks whether the value at position (i, j) is null.
`default boolean`	`isNullAt(int i, java.lang.String field)` Checks whether the field value is null.
`default LongVector`	`longVector(java.lang.Enum<?> e)` Selects column using an enum value.
`LongVector`	`longVector(int i)` Selects column based on the column index.
`default LongVector`	`longVector(java.lang.String colName)` Selects column based on the column name.
`static java.util.stream.Collector<Tuple,java.util.List<Tuple>,Matrix>`	`matrix()` Returns a stream collector that accumulates tuples into a Matrix.
`default Measure[]`	`measures()` Returns the column measures.
`DataFrame`	`merge(BaseVector... vectors)` Merges data frames horizontally by columns.
`DataFrame`	`merge(DataFrame... dataframes)` Merges data frames horizontally by columns.
`default java.lang.String[]`	`names()` Returns the column names.
`int`	`ncols()` Returns the number of columns.
`default int`	`nrows()` Returns the number of rows.
`static DataFrame`	`of(BaseVector... vectors)` Creates a DataFrame from a set of vectors.
`default DataFrame`	`of(boolean... index)` Returns a new data frame with boolean indexing.
`static <T> DataFrame`	`of(java.util.Collection<java.util.Map<java.lang.String,T>> data, StructType schema)` Creates a DataFrame from a set of Maps.
`static DataFrame`	`of(double[][] data, java.lang.String... names)` Creates a DataFrame from a 2-dimensional array.
`static DataFrame`	`of(float[][] data, java.lang.String... names)` Creates a DataFrame from a 2-dimensional array.
`default DataFrame`	`of(int... index)` Returns a new data frame with row indexing.
`static DataFrame`	`of(int[][] data, java.lang.String... names)` Creates a DataFrame from a 2-dimensional array.
`static DataFrame`	`of(java.util.List<? extends Tuple> data)` Creates a DataFrame from a set of tuples.
`static DataFrame`	`of(java.util.List<? extends Tuple> data, StructType schema)` Creates a DataFrame from a set of tuples.
`static <T> DataFrame`	`of(java.util.List<T> data, java.lang.Class<T> clazz)` Creates a DataFrame from a collection.
`static DataFrame`	`of(java.sql.ResultSet rs)` Creates a DataFrame from a JDBC ResultSet.
`static DataFrame`	`of(java.util.stream.Stream<? extends Tuple> data)` Creates a DataFrame from a stream of tuples.
`static DataFrame`	`of(java.util.stream.Stream<? extends Tuple> data, StructType schema)` Creates a DataFrame from a stream of tuples.
`default DataFrame`	`omitNullRows()` Returns a new data frame without rows that have null/missing values.
`StructType`	`schema()` Returns the schema of DataFrame.
`DataFrame`	`select(int... cols)` Selects a new DataFrame with given column indices.
`default DataFrame`	`select(java.lang.String... cols)` Selects a new DataFrame with given column names.
`default ShortVector`	`shortVector(java.lang.Enum<?> e)` Selects column using an enum value.
`ShortVector`	`shortVector(int i)` Selects column based on the column index.
`default ShortVector`	`shortVector(java.lang.String colName)` Selects column based on the column name.
`default DataFrame`	`slice(int from, int to)` Copies the specified range into a new data frame.
`default StringVector`	`stringVector(java.lang.Enum<?> e)` Selects column using an enum value.
`StringVector`	`stringVector(int i)` Selects column based on the column index.
`default StringVector`	`stringVector(java.lang.String colName)` Selects column based on the column name.
`default DataFrame`	`structure()` Returns the structure of data frame.
`default DataFrame`	`summary()` Returns the statistic summary of numeric columns.
`default double[][]`	`toArray()` Return an array obtained by converting all the variables in a data frame to numeric mode and then binding them together as the columns of a matrix.
`default double[][]`	`toArray(boolean bias, CategoricalEncoder encoder)` Return an array obtained by converting all the variables in a data frame to numeric mode and then binding them together as the columns of a matrix.
`default Matrix`	`toMatrix()` Return a matrix obtained by converting all the variables in a data frame to numeric mode and then binding them together as the columns of a matrix.
`default Matrix`	`toMatrix(boolean bias, CategoricalEncoder encoder, java.lang.String rowNames)` Return a matrix obtained by converting all the variables in a data frame to numeric mode and then binding them together as the columns of a matrix.
`default java.lang.String`	`toString(int numRows)` Returns the string representation of top rows.
`default java.lang.String`	`toString(int numRows, boolean truncate)` Returns the string representation of top rows.
`default java.lang.String`	`toString(int i, int j)` Returns the string representation of the value at position (i, j).
`default java.lang.String`	`toString(int i, java.lang.String field)` Returns the string representation of the field value.
`default java.lang.String[][]`	`toStrings(int numRows)` Returns the string representation of top rows.
`default java.lang.String[][]`	`toStrings(int numRows, boolean truncate)` Returns the string representation of top rows.
`default DataType[]`	`types()` Returns the column types.
`DataFrame`	`union(DataFrame... dataframes)` Merges data frames vertically by rows.
`default <T> Vector<T>`	`vector(java.lang.Enum<?> e)` Selects column using an enum value.
`<T> Vector<T>`	`vector(int i)` Selects column based on the column index.
`default <T> Vector<T>`	`vector(java.lang.String colName)` Selects column based on the column name.

Methods inherited from interface smile.data.Dataset
apply, distributed, get, isEmpty, of, size, stream, toDataset, toMatrix

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

- Method Detail
  - schema
```
StructType schema()
```
    Returns the schema of DataFrame.
  - names
```
default java.lang.String[] names()
```
    Returns the column names.
  - types
```
default DataType[] types()
```
    Returns the column types.
  - measures
```
default Measure[] measures()
```
    Returns the column measures.
  - nrows
```
default int nrows()
```
    Returns the number of rows.
  - ncols
```
int ncols()
```
    Returns the number of columns.
  - structure
```
default DataFrame structure()
```
    Returns the structure of data frame.
  - omitNullRows
```
default DataFrame omitNullRows()
```
    Returns a new data frame without rows that have null/missing values.
  - get
```
default java.lang.Object get(int i,
                             int j)
```
    Returns the cell at (i, j).
  - get
```
default java.lang.Object get(int i,
                             java.lang.String field)
```
    Returns the cell at (i, j).
  - of
```
default DataFrame of(int... index)
```
    Returns a new data frame with row indexing.
  - of
```
default DataFrame of(boolean... index)
```
    Returns a new data frame with boolean indexing.
  - slice
```
default DataFrame slice(int from,
                        int to)
```
    Copies the specified range into a new data frame.
    
    Parameters:
    
    from - the initial index of the range to be copied, inclusive
    
    to - the final index of the range to be copied, exclusive.
  - isNullAt
```
default boolean isNullAt(int i,
                         int j)
```
    Checks whether the value at position (i, j) is null.
  - isNullAt
```
default boolean isNullAt(int i,
                         java.lang.String field)
```
    Checks whether the field value is null.
  - getBoolean
```
default boolean getBoolean(int i,
                           int j)
```
    Returns the value at position (i, j) as a primitive boolean.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getBoolean
```
default boolean getBoolean(int i,
                           java.lang.String field)
```
    Returns the field value as a primitive boolean.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getChar
```
default char getChar(int i,
                     int j)
```
    Returns the value at position (i, j) as a primitive byte.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getChar
```
default char getChar(int i,
                     java.lang.String field)
```
    Returns the field value as a primitive byte.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getByte
```
default byte getByte(int i,
                     int j)
```
    Returns the value at position (i, j) as a primitive byte.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getByte
```
default byte getByte(int i,
                     java.lang.String field)
```
    Returns the field value as a primitive byte.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getShort
```
default short getShort(int i,
                       int j)
```
    Returns the value at position (i, j) as a primitive short.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getShort
```
default short getShort(int i,
                       java.lang.String field)
```
    Returns the field value as a primitive short.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getInt
```
default int getInt(int i,
                   int j)
```
    Returns the value at position (i, j) as a primitive int.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getInt
```
default int getInt(int i,
                   java.lang.String field)
```
    Returns the field value as a primitive int.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getLong
```
default long getLong(int i,
                     int j)
```
    Returns the value at position (i, j) as a primitive long.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getLong
```
default long getLong(int i,
                     java.lang.String field)
```
    Returns the field value as a primitive long.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getFloat
```
default float getFloat(int i,
                       int j)
```
    Returns the value at position (i, j) as a primitive float. Throws an exception if the type mismatches or if the value is null.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getFloat
```
default float getFloat(int i,
                       java.lang.String field)
```
    Returns the field value as a primitive float. Throws an exception if the type mismatches or if the value is null.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getDouble
```
default double getDouble(int i,
                         int j)
```
    Returns the value at position (i, j) as a primitive double.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getDouble
```
default double getDouble(int i,
                         java.lang.String field)
```
    Returns the field value as a primitive double.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
    
    java.lang.NullPointerException - when value is null.
  - getString
```
default java.lang.String getString(int i,
                                   int j)
```
    Returns the value at position (i, j) as a String object.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getString
```
default java.lang.String getString(int i,
                                   java.lang.String field)
```
    Returns the field value as a String object.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - toString
```
default java.lang.String toString(int i,
                                  int j)
```
    Returns the string representation of the value at position (i, j).
  - toString
```
default java.lang.String toString(int i,
                                  java.lang.String field)
```
    Returns the string representation of the field value.
  - getDecimal
```
default java.math.BigDecimal getDecimal(int i,
                                        int j)
```
    Returns the value at position (i, j) of decimal type as java.math.BigDecimal.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getDecimal
```
default java.math.BigDecimal getDecimal(int i,
                                        java.lang.String field)
```
    Returns the field value of decimal type as java.math.BigDecimal.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getDate
```
default java.time.LocalDate getDate(int i,
                                    int j)
```
    Returns the value at position (i, j) of date type as java.time.LocalDate.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getDate
```
default java.time.LocalDate getDate(int i,
                                    java.lang.String field)
```
    Returns the field value of date type as java.time.LocalDate.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getTime
```
default java.time.LocalTime getTime(int i,
                                    int j)
```
    Returns the value at position (i, j) of date type as java.time.LocalTime.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getTime
```
default java.time.LocalTime getTime(int i,
                                    java.lang.String field)
```
    Returns the field value of date type as java.time.LocalTime.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getDateTime
```
default java.time.LocalDateTime getDateTime(int i,
                                            int j)
```
    Returns the value at position (i, j) as java.time.LocalDateTime.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getDateTime
```
default java.time.LocalDateTime getDateTime(int i,
                                            java.lang.String field)
```
    Returns the field value as java.time.LocalDateTime.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getScale
```
default java.lang.String getScale(int i,
                                  int j)
```
    Returns the value at position (i, j) of NominalScale or OrdinalScale.
    
    Throws:
    
    java.lang.ClassCastException - when the data is not nominal or ordinal.
  - getScale
```
default java.lang.String getScale(int i,
                                  java.lang.String field)
```
    Returns the field value of NominalScale or OrdinalScale.
    
    Throws:
    
    java.lang.ClassCastException - when the data is not nominal or ordinal.
  - getArray
```
default <T> T[] getArray(int i,
                         int j)
```
    Returns the value at position (i, j) of array type.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getArray
```
default <T> T[] getArray(int i,
                         java.lang.String field)
```
    Returns the field value of array type.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getStruct
```
default Tuple getStruct(int i,
                        int j)
```
    Returns the value at position (i, j) of struct type.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - getStruct
```
default Tuple getStruct(int i,
                        java.lang.String field)
```
    Returns the field value of struct type.
    
    Throws:
    
    java.lang.ClassCastException - when data type does not match.
  - columnIndex
```
int columnIndex(java.lang.String name)
```
    Returns the index of a given column name.
    
    Throws:
    
    java.lang.IllegalArgumentException - when a field `name` does not exist.
  - apply
```
default BaseVector apply(java.lang.String colName)
```
    Selects column based on the column name and return it as a Column.
  - apply
```
default BaseVector apply(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - column
```
BaseVector column(int i)
```
    Selects column based on the column index.
  - column
```
default BaseVector column(java.lang.String colName)
```
    Selects column based on the column name.
  - column
```
default BaseVector column(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - vector
```
<T> Vector<T> vector(int i)
```
    Selects column based on the column index.
  - vector
```
default <T> Vector<T> vector(java.lang.String colName)
```
    Selects column based on the column name.
  - vector
```
default <T> Vector<T> vector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - booleanVector
```
BooleanVector booleanVector(int i)
```
    Selects column based on the column index.
  - booleanVector
```
default BooleanVector booleanVector(java.lang.String colName)
```
    Selects column based on the column name.
  - booleanVector
```
default BooleanVector booleanVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - charVector
```
CharVector charVector(int i)
```
    Selects column based on the column index.
  - charVector
```
default CharVector charVector(java.lang.String colName)
```
    Selects column based on the column name.
  - charVector
```
default CharVector charVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - byteVector
```
ByteVector byteVector(int i)
```
    Selects column based on the column index.
  - byteVector
```
default ByteVector byteVector(java.lang.String colName)
```
    Selects column based on the column name.
  - byteVector
```
default ByteVector byteVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - shortVector
```
ShortVector shortVector(int i)
```
    Selects column based on the column index.
  - shortVector
```
default ShortVector shortVector(java.lang.String colName)
```
    Selects column based on the column name.
  - shortVector
```
default ShortVector shortVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - intVector
```
IntVector intVector(int i)
```
    Selects column based on the column index.
  - intVector
```
default IntVector intVector(java.lang.String colName)
```
    Selects column based on the column name.
  - intVector
```
default IntVector intVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - longVector
```
LongVector longVector(int i)
```
    Selects column based on the column index.
  - longVector
```
default LongVector longVector(java.lang.String colName)
```
    Selects column based on the column name.
  - longVector
```
default LongVector longVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - floatVector
```
FloatVector floatVector(int i)
```
    Selects column based on the column index.
  - floatVector
```
default FloatVector floatVector(java.lang.String colName)
```
    Selects column based on the column name.
  - floatVector
```
default FloatVector floatVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - doubleVector
```
DoubleVector doubleVector(int i)
```
    Selects column based on the column index.
  - doubleVector
```
default DoubleVector doubleVector(java.lang.String colName)
```
    Selects column based on the column name.
  - doubleVector
```
default DoubleVector doubleVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - stringVector
```
StringVector stringVector(int i)
```
    Selects column based on the column index.
  - stringVector
```
default StringVector stringVector(java.lang.String colName)
```
    Selects column based on the column name.
  - stringVector
```
default StringVector stringVector(java.lang.Enum<?> e)
```
    Selects column using an enum value.
  - select
```
DataFrame select(int... cols)
```
    Selects a new DataFrame with given column indices.
  - select
```
default DataFrame select(java.lang.String... cols)
```
    Selects a new DataFrame with given column names.
  - drop
```
DataFrame drop(int... cols)
```
    Returns a new DataFrame without given column indices.
  - merge
```
DataFrame merge(DataFrame... dataframes)
```
    Merges data frames horizontally by columns.
    
    Returns:
    
    a new data frame that combines this DataFrame with one more more other DataFrames by columns.
  - merge
```
DataFrame merge(BaseVector... vectors)
```
    Merges data frames horizontally by columns.
    
    Returns:
    
    a new data frame that combines this DataFrame with one more more additional vectors.
  - union
```
DataFrame union(DataFrame... dataframes)
```
    Merges data frames vertically by rows.
    
    Returns:
    
    a new data frame that combines all the rows.
  - drop
```
default DataFrame drop(java.lang.String... cols)
```
    Returns a new DataFrame without given column names.
  - factorize
```
default DataFrame factorize(java.lang.String... cols)
```
    Returns a new DataFrame with given columns converted to nominal.
    
    Parameters:
    
    cols - column names. If empty, all object columns in the data frame will be converted.
    
    Returns:
    
    a new DataFrame.
  - toArray
```
default double[][] toArray()
```
    Return an array obtained by converting all the variables in a data frame to numeric mode and then binding them together as the columns of a matrix. Missing values/nulls will be encoded as Double.NaN. No bias term and uses level encoding for categorical variables.
  - toArray
```
default double[][] toArray(boolean bias,
                           CategoricalEncoder encoder)
```
    Return an array obtained by converting all the variables in a data frame to numeric mode and then binding them together as the columns of a matrix. Missing values/nulls will be encoded as Double.NaN.
    
    Parameters:
    
    bias - if true, add the first column of all 1's.
    
    encoder - the categorical variable encoder.
  - toMatrix
```
default Matrix toMatrix()
```
    Return a matrix obtained by converting all the variables in a data frame to numeric mode and then binding them together as the columns of a matrix. Missing values/nulls will be encoded as Double.NaN.
  - toMatrix
```
default Matrix toMatrix(boolean bias,
                        CategoricalEncoder encoder,
                        java.lang.String rowNames)
```
    Return a matrix obtained by converting all the variables in a data frame to numeric mode and then binding them together as the columns of a matrix. Missing values/nulls will be encoded as Double.NaN. No bias term and uses level encoding for categorical variables.
    
    Parameters:
    
    bias - if true, add the first column of all 1's.
    
    encoder - the categorical variable encoder.
    
    rowNames - the column to be used as row names.
  - summary
```
default DataFrame summary()
```
    Returns the statistic summary of numeric columns.
  - toString
```
default java.lang.String toString(int numRows)
```
    Returns the string representation of top rows.
    
    Specified by:
    
    toString in interface Dataset<Tuple>
    
    Parameters:
    
    numRows - Number of rows to show
  - toString
```
default java.lang.String toString(int numRows,
                                  boolean truncate)
```
    Returns the string representation of top rows.
    
    Parameters:
    
    numRows - Number of rows to show
    
    truncate - Whether truncate long strings and align cells right.
  - toStrings
```
default java.lang.String[][] toStrings(int numRows)
```
    Returns the string representation of top rows.
    
    Parameters:
    
    numRows - Number of rows to show
  - toStrings
```
default java.lang.String[][] toStrings(int numRows,
                                       boolean truncate)
```
    Returns the string representation of top rows.
    
    Parameters:
    
    numRows - Number of rows to show
    
    truncate - Whether truncate long strings.
  - of
```
static DataFrame of(BaseVector... vectors)
```
    Creates a DataFrame from a set of vectors.
    
    Parameters:
    
    vectors - The column vectors.
  - of
```
static DataFrame of(double[][] data,
                    java.lang.String... names)
```
    Creates a DataFrame from a 2-dimensional array.
    
    Parameters:
    
    data - The data array.
    
    names - the name of columns.
  - of
```
static DataFrame of(float[][] data,
                    java.lang.String... names)
```
    Creates a DataFrame from a 2-dimensional array.
    
    Parameters:
    
    data - The data array.
    
    names - the name of columns.
  - of
```
static DataFrame of(int[][] data,
                    java.lang.String... names)
```
    Creates a DataFrame from a 2-dimensional array.
    
    Parameters:
    
    data - The data array.
    
    names - the name of columns.
  - of
```
static <T> DataFrame of(java.util.List<T> data,
                        java.lang.Class<T> clazz)
```
    Creates a DataFrame from a collection.
    
    Type Parameters:
    
    T - The type of elements.
    
    Parameters:
    
    data - The data collection.
    
    clazz - The class type of elements.
  - of
```
static DataFrame of(java.util.stream.Stream<? extends Tuple> data)
```
    Creates a DataFrame from a stream of tuples.
    
    Parameters:
    
    data - The data stream.
  - of
```
static DataFrame of(java.util.stream.Stream<? extends Tuple> data,
                    StructType schema)
```
    Creates a DataFrame from a stream of tuples.
    
    Parameters:
    
    data - The data stream.
  - of
```
static DataFrame of(java.util.List<? extends Tuple> data)
```
    Creates a DataFrame from a set of tuples.
    
    Parameters:
    
    data - The data collection.
  - of
```
static DataFrame of(java.util.List<? extends Tuple> data,
                    StructType schema)
```
    Creates a DataFrame from a set of tuples.
    
    Parameters:
    
    data - The data collection.
  - of
```
static <T> DataFrame of(java.util.Collection<java.util.Map<java.lang.String,T>> data,
                        StructType schema)
```
    Creates a DataFrame from a set of Maps.
    
    Parameters:
    
    data - The data collection.
  - of
```
static DataFrame of(java.sql.ResultSet rs)
             throws java.sql.SQLException
```
    Creates a DataFrame from a JDBC ResultSet.
    
    Parameters:
    
    rs - The JDBC result set.
    
    Throws:
    
    java.sql.SQLException
  - collect
```
static <T> java.util.stream.Collector<T,java.util.List<T>,DataFrame> collect(java.lang.Class<T> clazz)
```
    Returns a stream collector that accumulates objects into a DataFrame.
    
    Type Parameters:
    
    T - the type of input elements to the reduction operation
    
    Parameters:
    
    clazz - The class type of elements.
  - collect
```
static java.util.stream.Collector<Tuple,java.util.List<Tuple>,DataFrame> collect()
```
    Returns a stream collector that accumulates tuples into a DataFrame.
  - matrix
```
static java.util.stream.Collector<Tuple,java.util.List<Tuple>,Matrix> matrix()
```
    Returns a stream collector that accumulates tuples into a Matrix.

Interface DataFrame

Method Summary

Methods inherited from interface smile.data.Dataset

Methods inherited from interface java.lang.Iterable

Method Detail

schema

names

types

measures

nrows

ncols

structure

omitNullRows

get

get

of

of

slice

isNullAt

isNullAt

getBoolean

getBoolean

getChar

getChar

getByte

getByte

getShort

getShort

getInt

getInt

getLong

getLong

getFloat

getFloat

getDouble

getDouble

getString

getString

toString

toString

getDecimal

getDecimal

getDate

getDate

getTime

getTime

getDateTime

getDateTime

getScale

getScale

getArray

getArray

getStruct

getStruct

columnIndex

apply

apply

column

column

column

vector

vector

vector

booleanVector

booleanVector

booleanVector

charVector

charVector

charVector

byteVector

byteVector

byteVector

shortVector

shortVector

shortVector

intVector

intVector

intVector

longVector

longVector