/*
* Seldon -- open source prediction engine
* =======================================
* Copyright 2011-2015 Seldon Technologies Ltd and Rummble Ltd (http://www.seldon.io/)
*
**********************************************************************************************
*
* 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.
*
**********************************************************************************************
*/
package io.seldon.stream.itemsim;
import io.seldon.stream.itemsim.minhash.Hasher;
import io.seldon.stream.itemsim.minhash.SimplePrimeHash;
import java.util.Random;
import org.junit.Assert;
import org.junit.Test;
public class RollingWindowedMinHashTest {
@Test
public void testDecreasingMinHash()
{
Hasher h = new SimplePrimeHash(1,2);
RollingWindowedMinHash mh = new RollingWindowedMinHash(h, 10);
for(int i=10;i>=1;i--)
{
mh.add(i, 11-i);
}
Assert.assertEquals(1, mh.hashes.size());
Assert.assertEquals(10, mh.getCount(10));
}
@Test
public void testIncreasingMinHash()
{
Hasher h = new SimplePrimeHash(1,2);
RollingWindowedMinHash mh = new RollingWindowedMinHash(h, 10);
for(int i=0;i<=10;i++)
{
mh.add(i, i);
}
Assert.assertEquals(10, mh.hashes.size());
Assert.assertEquals(10, mh.getCount(10));
}
@Test
public void sizeTest()
{
Hasher h = new SimplePrimeHash(1,2);
RollingWindowedMinHash mh = new RollingWindowedMinHash(h, 10000);
Random r = new Random();
int timeSteps = 100000;
for(int i=1;i<timeSteps;i++)
{
int id = r.nextInt(2000);
mh.add(id, i);
}
System.out.println(mh.hashes.size());
}
}