org.apache.mahout.classifier.df.data.DataConverter Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of mahout-mr Show documentation
Show all versions of mahout-mr Show documentation
Scalable machine learning libraries
/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.
*/
package org.apache.mahout.classifier.df.data;
import com.google.common.base.Preconditions;
import org.apache.commons.lang3.ArrayUtils;
import org.apache.mahout.math.DenseVector;
import java.util.regex.Pattern;
/**
* Converts String to Instance using a Dataset
*/
@Deprecated
public class DataConverter {
private static final Pattern COMMA_SPACE = Pattern.compile("[, ]");
private final Dataset dataset;
public DataConverter(Dataset dataset) {
this.dataset = dataset;
}
public Instance convert(CharSequence string) {
// all attributes (categorical, numerical, label), ignored
int nball = dataset.nbAttributes() + dataset.getIgnored().length;
String[] tokens = COMMA_SPACE.split(string);
Preconditions.checkArgument(tokens.length == nball,
"Wrong number of attributes in the string: " + tokens.length + ". Must be " + nball);
int nbattrs = dataset.nbAttributes();
DenseVector vector = new DenseVector(nbattrs);
int aId = 0;
for (int attr = 0; attr < nball; attr++) {
if (!ArrayUtils.contains(dataset.getIgnored(), attr)) {
String token = tokens[attr].trim();
if ("?".equals(token)) {
// missing value
return null;
}
if (dataset.isNumerical(aId)) {
vector.set(aId++, Double.parseDouble(token));
} else { // CATEGORICAL
vector.set(aId, dataset.valueOf(aId, token));
aId++;
}
}
}
return new Instance(vector);
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy