/*
* 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.utils.vectors;
import com.google.common.collect.Iterables;
import org.apache.mahout.math.SequentialAccessSparseVector;
import org.apache.mahout.math.Vector;
import org.apache.mahout.utils.MahoutTestCase;
import org.junit.Test;
public final class VectorHelperTest extends MahoutTestCase {
@Test
public void testJsonFormatting() throws Exception {
Vector v = new SequentialAccessSparseVector(10);
v.set(2, 3.1);
v.set(4, 1.0);
v.set(6, 8.1);
v.set(7, -100);
v.set(9, 12.2);
String UNUSED = "UNUSED";
String[] dictionary = {
UNUSED, UNUSED, "two", UNUSED, "four", UNUSED, "six", "seven", UNUSED, "nine"
};
assertEquals("sorted json form incorrect: ", "{nine:12.2,six:8.1,two:3.1}",
VectorHelper.vectorToJson(v, dictionary, 3, true));
assertEquals("unsorted form incorrect: ", "{two:3.1,four:1.0}",
VectorHelper.vectorToJson(v, dictionary, 2, false));
assertEquals("sorted json form incorrect: ", "{nine:12.2,six:8.1,two:3.1,four:1.0}",
VectorHelper.vectorToJson(v, dictionary, 4, true));
assertEquals("sorted json form incorrect: ", "{nine:12.2,six:8.1,two:3.1,four:1.0,seven:-100.0}",
VectorHelper.vectorToJson(v, dictionary, 5, true));
assertEquals("sorted json form incorrect: ", "{nine:12.2,six:8.1}",
VectorHelper.vectorToJson(v, dictionary, 2, true));
assertEquals("unsorted form incorrect: ", "{two:3.1,four:1.0}",
VectorHelper.vectorToJson(v, dictionary, 2, false));
}
@Test
public void testTopEntries() throws Exception {
Vector v = new SequentialAccessSparseVector(10);
v.set(2, 3.1);
v.set(4, 1.0);
v.set(6, 8.1);
v.set(7, -100);
v.set(9, 12.2);
v.set(1, 0.0);
v.set(3, 0.0);
v.set(8, 2.7);
// check if sizeOFNonZeroElementsInVector = maxEntries
assertEquals(6, VectorHelper.topEntries(v, 6).size());
// check if sizeOfNonZeroElementsInVector < maxEntries
assertTrue(VectorHelper.topEntries(v, 9).size() < 9);
// check if sizeOfNonZeroElementsInVector > maxEntries
assertTrue(VectorHelper.topEntries(v, 5).size() < Iterables.size(v.nonZeroes()));
}
@Test
public void testTopEntriesWhenAllZeros() throws Exception {
Vector v = new SequentialAccessSparseVector(10);
v.set(2, 0.0);
v.set(4, 0.0);
v.set(6, 0.0);
v.set(7, 0);
v.set(9, 0.0);
v.set(1, 0.0);
v.set(3, 0.0);
v.set(8, 0.0);
assertEquals(0, VectorHelper.topEntries(v, 6).size());
}
}