src/test/java/org/apache/datasketches/hive/quantiles/GetCdfFromStringsSketchUDFTest.java

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 * 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
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 *
 * http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.datasketches.hive.quantiles;

import java.util.Comparator;
import java.util.List;

import org.apache.hadoop.io.BytesWritable;

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

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

@SuppressWarnings("javadoc")
public class GetCdfFromStringsSketchUDFTest {

  static final Comparator<String> comparator = Comparator.naturalOrder();
  static final ArrayOfItemsSerDe<String> serDe = new ArrayOfStringsSerDe();

  @Test
  public void nullSketch() {
    List<Double> result = new GetCdfFromStringsSketchUDF().evaluate(null, "");
    Assert.assertNull(result);
  }

  @Test
  public void emptyListOfSplitPoints() {
    ItemsSketch<String> sketch = ItemsSketch.getInstance(comparator);
    sketch.update("a");
    sketch.update("b");
    sketch.update("c");
    List<Double> result = new GetCdfFromStringsSketchUDF().evaluate(new BytesWritable(sketch.toByteArray(serDe)));
    Assert.assertNotNull(result);
    Assert.assertEquals(result.size(), 1);
    Assert.assertEquals(result.get(0), 1.0);
  }

  @Test
  public void emptySketch() {
    ItemsSketch<String> sketch = ItemsSketch.getInstance(comparator);
    List<Double> result = new GetCdfFromStringsSketchUDF().evaluate(new BytesWritable(sketch.toByteArray(serDe)), "a");
    Assert.assertNull(result);
  }

  @Test
  public void normalCase() {
    ItemsSketch<String> sketch = ItemsSketch.getInstance(comparator);
    sketch.update("a");
    sketch.update("b");
    sketch.update("c");
    sketch.update("d");
    List<Double> result = new GetCdfFromStringsSketchUDF().evaluate(new BytesWritable(sketch.toByteArray(serDe)), "a", "c", "d");
    Assert.assertNotNull(result);
    Assert.assertEquals(result.size(), 4);
    Assert.assertEquals(result.get(0), 0.0);
    Assert.assertEquals(result.get(1), 0.5);
    Assert.assertEquals(result.get(2), 0.75);
    Assert.assertEquals(result.get(3), 1.0);
  }

}