public abstract class SimpleStreamFilter extends SimpleFilter implements StreamableFilter
true
. SomeFilter
on a
dataset that is loaded from filename
.
import weka.core.*; import weka.filters.*; import java.io.*; ... SomeFilter filter = new SomeFilter(); // set necessary options for the filter Instances data = new Instances( new BufferedReader( new FileReader(filename))); Instances filteredData = Filter.useFilter(data, filter);Implementation:
public static void main(String[] args) { runFilter(new <Filtername>(), args); }Example implementation:
import weka.core.*; import weka.core.Capabilities.*; import weka.filters.*; import java.util.Random; public class SimpleStream extends SimpleStreamFilter { public String globalInfo() { return "A simple stream filter that adds an attribute 'bla' at the end containing a random number."; } public Capabilities getCapabilities() { Capabilities result = super.getCapabilities(); result.enableAllAttributes(); result.enableAllClasses(); result.enable(Capability.NO_CLASS); // filter doesn't need class to be set return result; } protected Instances determineOutputFormat(Instances inputFormat) { Instances result = new Instances(inputFormat, 0); result.insertAttributeAt(new Attribute("bla"), result.numAttributes()); return result; } protected Instance process(Instance inst) { double[] values = new double[inst.numAttributes() + 1]; for (int n = 0; n < inst.numAttributes(); n++) values[n] = inst.value(n); values[values.length - 1] = new Random().nextInt(); Instance result = new Instance(1, values); return result; } public static void main(String[] args) { runFilter(new SimpleStream(), args); } }Options:
SimpleBatchFilter
,
input(Instance)
,
batchFinished()
,
Filter.m_FirstBatchDone
,
Serialized FormConstructor and Description |
---|
SimpleStreamFilter() |
Modifier and Type | Method and Description |
---|---|
boolean |
batchFinished()
Signify that this batch of input to the filter is finished.
|
boolean |
input(Instance instance)
Input an instance for filtering.
|
debugTipText, getDebug, getOptions, globalInfo, listOptions, setDebug, setInputFormat, setOptions
batchFilterFile, filterFile, getCapabilities, getCapabilities, getOutputFormat, getRevision, isFirstBatchDone, isNewBatch, isOutputFormatDefined, main, makeCopies, makeCopy, numPendingOutput, output, outputPeek, toString, useFilter, wekaStaticWrapper
public boolean input(Instance instance) throws Exception
input
in class Filter
instance
- the input instanceIllegalStateException
- if no input structure has been definedException
- if something goes wrongpublic boolean batchFinished() throws Exception
batchFinished
in class Filter
IllegalStateException
- if no input format has been set.NullPointerException
- if no input structure has been defined,Exception
- if there was a problem finishing the batch.Copyright © 2019 University of Waikato, Hamilton, NZ. All rights reserved.