PivotTransform

java.lang.Object
- org.datavec.api.transform.transform.BaseTransform
- - org.datavec.api.transform.transform.categorical.PivotTransform

All Implemented Interfaces:

java.io.Serializable, ColumnOp, Transform
```
public class PivotTransform
extends BaseTransform
```
Pivot transform operates on two columns: - a categorical column that operates as a key, and - Another column that contains a value Essentially, Pivot transform takes keyvalue pairs and breaks them out into separate columns. For example, with schema [col0, key, value, col3] and values with key in {a,b,c} Output schema is [col0, key[a], key[b], key[c], col3] and input (col0Val, b, x, col3Val) gets mapped to (col0Val, 0, x, 0, col3Val). When expanding columns, a default value is used - for example 0 for numerical columns.

See Also:

Serialized Form

Field Summary
- Fields inherited from class org.datavec.api.transform.transform.BaseTransform
  inputSchema

Constructor Summary

Constructors
Constructor and Description
`PivotTransform(java.lang.String keyColumnName, java.lang.String valueColumnName)`
`PivotTransform(java.lang.String keyColumnName, java.lang.String valueColumnName, Writable defaultValue)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`java.lang.String`	`columnName()` Returns a singular column name this op is meant to run on
`java.lang.String[]`	`columnNames()` Returns column names this op is meant to run on
`java.util.List<Writable>`	`map(java.util.List<Writable> writables)` Transform a writable in to another writable
`java.lang.Object`	`map(java.lang.Object input)` Transform an object in to another object
`java.lang.Object`	`mapSequence(java.lang.Object sequence)` Transform a sequence
`java.lang.String`	`outputColumnName()` The output column name after the operation has been applied
`java.lang.String[]`	`outputColumnNames()` The output column names This will often be the same as the input
`Schema`	`transform(Schema inputSchema)` Get the output schema for this transformation, given an input schema

Methods inherited from class org.datavec.api.transform.transform.BaseTransform
getInputSchema, mapSequence, setInputSchema, toString

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

- Constructor Detail
  - PivotTransform
```
public PivotTransform(java.lang.String keyColumnName,
                      java.lang.String valueColumnName)
```
    Parameters:
    
    keyColumnName - Key column to expand
    
    valueColumnName - Name of the column that contains the value
  - PivotTransform
```
public PivotTransform(java.lang.String keyColumnName,
                      java.lang.String valueColumnName,
                      Writable defaultValue)
```
    Parameters:
    
    keyColumnName - Key column to expand
    
    valueColumnName - Name of the column that contains the value
    
    defaultValue - The default value to use in expanded columns.
- Method Detail
  - transform
```
public Schema transform(Schema inputSchema)
```
    Description copied from interface: ColumnOp
    
    Get the output schema for this transformation, given an input schema
  - outputColumnName
```
public java.lang.String outputColumnName()
```
    Description copied from interface: ColumnOp
    
    The output column name after the operation has been applied
    
    Returns:
    
    the output column name
  - outputColumnNames
```
public java.lang.String[] outputColumnNames()
```
    Description copied from interface: ColumnOp
    
    The output column names This will often be the same as the input
    
    Returns:
    
    the output column names
  - columnNames
```
public java.lang.String[] columnNames()
```
    Description copied from interface: ColumnOp
    
    Returns column names this op is meant to run on
    
    Returns:
  - columnName
```
public java.lang.String columnName()
```
    Description copied from interface: ColumnOp
    
    Returns a singular column name this op is meant to run on
    
    Returns:
  - map
```
public java.util.List<Writable> map(java.util.List<Writable> writables)
```
    Description copied from interface: Transform
    
    Transform a writable in to another writable
    
    Parameters:
    
    writables - the record to transform
    
    Returns:
    
    the transformed writable
  - map
```
public java.lang.Object map(java.lang.Object input)
```
    Description copied from interface: Transform
    
    Transform an object in to another object
    
    Parameters:
    
    input - the record to transform
    
    Returns:
    
    the transformed writable
  - mapSequence
```
public java.lang.Object mapSequence(java.lang.Object sequence)
```
    Description copied from interface: Transform
    
    Transform a sequence

Class PivotTransform

Field Summary

Fields inherited from class org.datavec.api.transform.transform.BaseTransform

Constructor Summary

Method Summary

Methods inherited from class org.datavec.api.transform.transform.BaseTransform

Methods inherited from class java.lang.Object

Constructor Detail

PivotTransform

PivotTransform

Method Detail

transform

outputColumnName

outputColumnNames

columnNames

columnName

map

map

mapSequence