src/test/java/org/apache/datasketches/pig/quantiles/GetQuantilesFromStringsSketchTest.java

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 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
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 *
 * http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.datasketches.pig.quantiles;

import org.apache.datasketches.ArrayOfItemsSerDe;
import org.apache.datasketches.ArrayOfStringsSerDe;
import org.apache.datasketches.quantiles.ItemsSketch;

import java.util.Arrays;
import java.util.Comparator;

import org.apache.pig.EvalFunc;
import org.apache.pig.data.DataByteArray;
import org.apache.pig.data.Tuple;
import org.apache.pig.data.TupleFactory;

import org.testng.annotations.Test;
import org.testng.Assert;

@SuppressWarnings("javadoc")
public class GetQuantilesFromStringsSketchTest {

  private static final TupleFactory TUPLE_FACTORY = TupleFactory.getInstance();

  private static final Comparator<String> COMPARATOR = Comparator.naturalOrder();
  private static final ArrayOfItemsSerDe<String> SER_DE = new ArrayOfStringsSerDe();

  @Test
  public void emptySketch() throws Exception {
    EvalFunc<Tuple> func = new GetQuantilesFromStringsSketch();
    ItemsSketch<String> sketch = ItemsSketch.getInstance(COMPARATOR);
    Tuple resultTuple = func.exec(TUPLE_FACTORY.newTuple(Arrays.asList(new DataByteArray(sketch.toByteArray(SER_DE)), 0.5)));
    Assert.assertNull(resultTuple);
  }

  @Test(expectedExceptions = IllegalArgumentException.class)
  public void tooFewInputs() throws Exception {
    EvalFunc<Tuple> func = new GetQuantilesFromStringsSketch();
    func.exec(TUPLE_FACTORY.newTuple(1));
  }

  @Test(expectedExceptions = IllegalArgumentException.class)
  public void wrongTypeForSketch() throws Exception {
    EvalFunc<Tuple> func = new GetQuantilesFromStringsSketch();
    func.exec(TUPLE_FACTORY.newTuple(Arrays.asList(1.0, 1.0)));
  }

  @Test(expectedExceptions = IllegalArgumentException.class)
  public void wrongTypeForFractionOrNumberOfIntervals() throws Exception {
    EvalFunc<Tuple> func = new GetQuantilesFromStringsSketch();
    ItemsSketch<String> sketch = ItemsSketch.getInstance(COMPARATOR);
    sketch.update("a");
    func.exec(TUPLE_FACTORY.newTuple(Arrays.asList(new DataByteArray(sketch.toByteArray(SER_DE)), "")));
  }

  @Test(expectedExceptions = IllegalArgumentException.class)
  public void wrongTypeAmongFractions() throws Exception {
    EvalFunc<Tuple> func = new GetQuantilesFromStringsSketch();
    ItemsSketch<String> sketch = ItemsSketch.getInstance(COMPARATOR);
    sketch.update("a");
    func.exec(TUPLE_FACTORY.newTuple(Arrays.asList(new DataByteArray(sketch.toByteArray(SER_DE)), 0.0, 1)));
  }

  @Test
  public void oneFraction() throws Exception {
    EvalFunc<Tuple> func = new GetQuantilesFromStringsSketch();
    ItemsSketch<String> sketch = ItemsSketch.getInstance(COMPARATOR);
    for (int i = 1; i <= 10; i++) {
      sketch.update(String.format("%02d", i));
    }
    Tuple resultTuple = func.exec(TUPLE_FACTORY.newTuple(Arrays.asList(new DataByteArray(sketch.toByteArray(SER_DE)), 0.5)));
    Assert.assertNotNull(resultTuple);
    Assert.assertEquals(resultTuple.size(), 1);
    Assert.assertEquals(((String) resultTuple.get(0)), "06");
  }

  @Test
  public void severalFractions() throws Exception {
    EvalFunc<Tuple> func = new GetQuantilesFromStringsSketch();
    ItemsSketch<String> sketch = ItemsSketch.getInstance(COMPARATOR);
    for (int i = 1; i <= 10; i++) {
      sketch.update(String.format("%02d", i));
    }
    Tuple resultTuple = func.exec(TUPLE_FACTORY.newTuple(Arrays.asList(new DataByteArray(sketch.toByteArray(SER_DE)), 0.0, 0.5, 1.0)));
    Assert.assertNotNull(resultTuple);
    Assert.assertEquals(resultTuple.size(), 3);
    Assert.assertEquals(((String) resultTuple.get(0)), "01");
    Assert.assertEquals(((String) resultTuple.get(1)), "06");
    Assert.assertEquals(((String) resultTuple.get(2)), "10");
  }

  @Test
  public void numberOfEvenlySpacedIntervals() throws Exception {
    EvalFunc<Tuple> func = new GetQuantilesFromStringsSketch();
    ItemsSketch<String> sketch = ItemsSketch.getInstance(COMPARATOR);
    for (int i = 1; i <= 10; i++) {
      sketch.update(String.format("%02d", i));
    }
    Tuple resultTuple = func.exec(TUPLE_FACTORY.newTuple(Arrays.asList(new DataByteArray(sketch.toByteArray(SER_DE)), 3)));
    Assert.assertNotNull(resultTuple);
    Assert.assertEquals(resultTuple.size(), 3);
    Assert.assertEquals(((String) resultTuple.get(0)), "01");
    Assert.assertEquals(((String) resultTuple.get(1)), "06");
    Assert.assertEquals(((String) resultTuple.get(2)), "10");
  }

}