magpie.attributes.selectors

Class PythonBasedAttributeSelector

java.lang.Object

magpie.attributes.selectors.BaseAttributeSelector

magpie.attributes.selectors.PythonBasedAttributeSelector

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable, Commandable, Options, Printable

Direct Known Subclasses:

LassoAttributeSelector, RandomForestAttributeSelector

public abstract class PythonBasedAttributeSelector
extends BaseAttributeSelector

Abstract class for performing attribute selection with a Python code. This class works by launching an external thread, and communicating with it via standard in and out.

The python code must take a CSV file via standard in as inputs, options as command line arguments, and return the result via standard out. The selected attributes should be listed by name on a line that starts with "[Answer]". Names should be separated by spaces.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
boolean	Debug Debug mode.

Fields inherited from class magpie.attributes.selectors.BaseAttributeSelector

trained

Constructor Summary

Constructors

Constructor and Description
PythonBasedAttributeSelector()

Method Summary

Modifier and Type	Method and Description
protected abstract java.util.List<java.lang.String>	assembleSystemCall(java.io.File codePath, Dataset data) Prepare the system call with all command-line arguments
protected abstract java.lang.String	getScriptPath() Get the path to the Python script to be run.
protected void	spawnStderrReader(java.lang.Process proc) Launch a thread that does nothing but read from the standard error of an external process.
protected java.util.List<java.lang.Integer>	train_protected(Dataset data) Operation that actually does the work for training.

Methods inherited from class magpie.attributes.selectors.BaseAttributeSelector

about, applyAttributeSelection, clone, getSelectionNames, getSelections, isTrained, printCommand, printDescription, printSelections, run, runCommand, train

Methods inherited from class java.lang.Object

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

Methods inherited from interface magpie.utility.interfaces.Options

printUsage, setOptions

Field Detail

Debug

public boolean Debug

Debug mode. Pipe output from subprocess to stdout

Constructor Detail

PythonBasedAttributeSelector

public PythonBasedAttributeSelector()

Method Detail

train_protected

protected java.util.List<java.lang.Integer> train_protected(Dataset data)

Description copied from class: BaseAttributeSelector

Operation that actually does the work for training. Must generate a list of attribute IDs

Specified by:

train_protected in class BaseAttributeSelector

Parameters:

data - Dataset used to train selector

Returns:

List of indexes of selected attributes

assembleSystemCall

protected abstract java.util.List<java.lang.String> assembleSystemCall(java.io.File codePath,
                                                                       Dataset data)

Prepare the system call with all command-line arguments

Parameters:

codePath - Path to executable or script to be run

data - Dataset being used to train attribute selector

Returns:

Command to be executed

getScriptPath

protected abstract java.lang.String getScriptPath()

Get the path to the Python script to be run.

Returns:

Path

spawnStderrReader

protected void spawnStderrReader(java.lang.Process proc)

Launch a thread that does nothing but read from the standard error of an external process. Prevents the subprocess from stalling due to a locked buffer.

Parameters:

proc - Process to be read from.