org.datavec.api.transform.stringreduce

Class StringReducer.Builder

java.lang.Object

org.datavec.api.transform.stringreduce.StringReducer.Builder

Enclosing class:

StringReducer

public static class StringReducer.Builder
extends Object

Constructor Summary

Constructors

Constructor and Description
Builder(StringReduceOp defaultOp) Create a StringReducer builder, and set the default column reduction operation.

Method Summary

Modifier and Type	Method and Description
StringReducer.Builder	appendColumns(String... columns) Reduce the specified columns by taking the minimum value
StringReducer	build()
StringReducer.Builder	customReduction(String column, ColumnReduction columnReduction) Reduce the specified column using a custom column reduction functionality.
StringReducer.Builder	inputColumns(List<String> inputColumns)
StringReducer.Builder	mergeColumns(String... columns) Reduce the specified columns by taking the sum of values
StringReducer.Builder	outputColumnName(String outputColumnName)
StringReducer.Builder	prependColumns(String... columns) Reduce the specified columns by taking the maximum value
StringReducer.Builder	replaceColumn(String... columns) Reduce the specified columns by taking the mean of the values
StringReducer.Builder	setIgnoreInvalid(String... columns) When doing the reduction: set the specified columns to ignore any invalid values.

Methods inherited from class java.lang.Object

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

Constructor Detail

Builder

public Builder(StringReduceOp defaultOp)

Create a StringReducer builder, and set the default column reduction operation. For any columns that aren't specified explicitly, they will use the default reduction operation. If a column does have a reduction operation explicitly specified, then it will override the default specified here.

Parameters:

defaultOp - Default reduction operation to perform

Method Detail

inputColumns

public StringReducer.Builder inputColumns(List<String> inputColumns)

outputColumnName

public StringReducer.Builder outputColumnName(String outputColumnName)

appendColumns

public StringReducer.Builder appendColumns(String... columns)

Reduce the specified columns by taking the minimum value

prependColumns

public StringReducer.Builder prependColumns(String... columns)

Reduce the specified columns by taking the maximum value

mergeColumns

public StringReducer.Builder mergeColumns(String... columns)

Reduce the specified columns by taking the sum of values

replaceColumn

public StringReducer.Builder replaceColumn(String... columns)

Reduce the specified columns by taking the mean of the values

customReduction

public StringReducer.Builder customReduction(String column,
                                             ColumnReduction columnReduction)

Reduce the specified column using a custom column reduction functionality.

Parameters:

column - Column to execute the custom reduction functionality on

columnReduction - Column reduction to execute on that column

setIgnoreInvalid

public StringReducer.Builder setIgnoreInvalid(String... columns)

When doing the reduction: set the specified columns to ignore any invalid values. Invalid: defined as being not valid according to the ColumnMetaData: ColumnMetaData.isValid(Writable). For numerical columns, this typically means being unable to parse the Writable. For example, Writable.toLong() failing for a Long column. If the column has any restrictions (min/max values, regex for Strings etc) these will also be taken into account.

Parameters:

columns - Columns to set 'ignore invalid' for

build

public StringReducer build()