/*
* Encog(tm) Core v3.4 - Java Version
* http://www.heatonresearch.com/encog/
* https://github.com/encog/encog-java-core
* Copyright 2008-2016 Heaton Research, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* For more information on Heaton Research copyrights, licenses
* and trademarks visit:
* http://www.heatonresearch.com/copyright
*/
package org.encog.ml.data.versatile.normalizers;
import org.encog.EncogError;
import org.encog.ml.data.MLData;
import org.encog.ml.data.versatile.columns.ColumnDefinition;
/**
* Normalize ordinal/nominal values to a single value that is simply the index
* of the class in the list. For example, "one", "two", "three" normalizes to
* 0,1,2.
*/
public class IndexedNormalizer implements Normalizer {
private static final long serialVersionUID = 1L;
@Override
public boolean equals(Object obj) {
return ( obj instanceof IndexedNormalizer );
}
/**
* {@inheritDoc}
*/
@Override
public int outputSize(ColumnDefinition colDef) {
return 1;
}
/**
* {@inheritDoc}
*/
@Override
public int normalizeColumn(ColumnDefinition colDef, String value,
double[] outputData, int outputColumn) {
if (!colDef.getClasses().contains(value)) {
throw new EncogError("Undefined value: " + value);
}
outputData[outputColumn] = colDef.getClasses().indexOf(value);
return outputColumn + 1;
}
/**
* {@inheritDoc}
*/
@Override
public String denormalizeColumn(ColumnDefinition colDef, MLData data,
int dataColumn) {
return colDef.getClasses().get((int) data.getData(dataColumn));
}
/**
* {@inheritDoc}
*/
@Override
public int normalizeColumn(ColumnDefinition colDef, double value,
double[] outputData, int outputColumn) {
throw new EncogError(
"Can't use an indexed normalizer on a continuous value: "
+ value);
}
}