| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * 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 org.chromium.latency.walt; |
| |
| import org.junit.Test; |
| |
| import java.util.ArrayList; |
| import java.util.Random; |
| |
| import static java.lang.Double.NaN; |
| import static junit.framework.Assert.assertEquals; |
| import static org.hamcrest.core.Is.is; |
| import static org.junit.Assert.assertThat; |
| |
| public class UtilsTest { |
| |
| @Test |
| public void testMedian_singleNumber() { |
| ArrayList<Double> arr = new ArrayList<>(); |
| arr.add(0d); |
| assertThat(Utils.median(arr), is(0d)); |
| } |
| |
| @Test |
| public void testMedian_evenSize() { |
| ArrayList<Double> arr = new ArrayList<>(); |
| arr.add(1d); arr.add(2d); arr.add(3d); arr.add(4d); |
| assertThat(Utils.median(arr), is(2.5d)); |
| } |
| |
| @Test |
| public void testMedian_oddSize() { |
| ArrayList<Double> arr = new ArrayList<>(); |
| arr.add(1d); arr.add(2d); arr.add(3d); arr.add(4d); arr.add(5d); |
| assertThat(Utils.median(arr), is(3d)); |
| } |
| |
| @Test |
| public void testMean() { |
| assertThat(Utils.mean(new double[]{-1,1,2,3}), is(1.25d)); |
| } |
| |
| @Test |
| public void testMean_singleNumber() { |
| assertThat(Utils.mean(new double[]{0}), is(0d)); |
| } |
| |
| @Test |
| public void testMean_empty() { |
| assertThat(Utils.mean(new double[]{}), is(NaN)); |
| } |
| |
| @Test |
| public void testMean_repeatedNumbers() { |
| assertThat(Utils.mean(new double[]{5,5,5,5}), is(5d)); |
| } |
| |
| @Test |
| public void testInterp() { |
| assertThat(Utils.interp(new double[]{5,6,16,17}, new double[]{0, 10, 12, 18}, |
| new double[]{35, 50, 75, 93}), is(new double[]{42.5, 44, 87, 90})); |
| } |
| |
| @Test |
| public void testInterp_singleNumber() { |
| assertThat(Utils.interp(new double[]{5}, new double[]{0, 10}, |
| new double[]{35, 50}), is(new double[]{42.5})); |
| } |
| |
| @Test |
| public void testInterp_twoNumbers() { |
| assertThat(Utils.interp(new double[]{0}, new double[]{0, 10}, |
| new double[]{35, 50}), is(new double[]{35})); |
| } |
| |
| @Test |
| public void testInterp_numberContained() { |
| assertThat(Utils.interp(new double[]{5, 10}, new double[]{0, 5, 10}, |
| new double[]{35, 19, 50}), is(new double[]{19, 50})); |
| } |
| |
| @Test |
| public void testStdev() { |
| assertThat(Utils.stdev(new double[]{10,12,14,18}), is(Math.sqrt(8.75))); |
| } |
| |
| @Test |
| public void testStdev_empty() { |
| assertThat(Utils.stdev(new double[]{}), is(NaN)); |
| } |
| |
| @Test |
| public void testStdev_singleNumber() { |
| assertThat(Utils.stdev(new double[]{42}), is(0d)); |
| } |
| |
| @Test |
| public void testStdev_manyNumbers() { |
| assertThat(Utils.stdev(new double[]{-1,0,1}), is(Math.sqrt(2d/3d))); |
| } |
| |
| @Test |
| public void testExtract() { |
| assertThat(Utils.extract(new int[]{1, 2, 2, 1, 2, 2, 1, 2, 2}, 1, |
| new double[]{1.5, 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, 8.5, 9.5}), |
| is(new double[]{1.5, 4.5, 7.5})); |
| } |
| |
| @Test |
| public void testExtract_empty() { |
| assertThat(Utils.extract(new int[]{}, 1, new double[]{}), is(new double[]{})); |
| } |
| |
| @Test |
| public void testArgmin() { |
| assertThat(Utils.argmin(new double[]{5, 2, 1, -10, -20, 5, 19, 100}), is(4)); |
| } |
| |
| @Test |
| public void testArgmin_empty() { |
| assertThat(Utils.argmin(new double[]{}), is(0)); |
| } |
| |
| @Test |
| public void testFindBestShift() { |
| Random rand = new Random(42); |
| double latency = 12.34; |
| double[] touchTimes = new double[4000]; |
| for (int i = 0; i < touchTimes.length; i++) { |
| // touch events every millisecond with some jitter |
| touchTimes[i] = i + rand.nextDouble()*0.2 - 0.1; |
| } |
| double[] touchY = new double[touchTimes.length]; |
| for (int i = 0; i < touchY.length; i++) { |
| // sine wave will oscillate 1 time |
| touchY[i] = 1000*Math.cos((touchTimes[i] - latency) * Math.PI/500) + rand.nextDouble()*0.02 - 0.01; |
| } |
| double[] laserTimes = new double[4]; |
| int i = 0; |
| for (int root = 0; root < 1000; root+=1000) { |
| laserTimes[i++] = root + 250 - 10; |
| laserTimes[i++] = root + 250 + 10; |
| laserTimes[i++] = root + 750 - 10; |
| laserTimes[i++] = root + 750 + 10; |
| } |
| assertEquals(latency, Utils.findBestShift(laserTimes, touchTimes, touchY), 1e-6); |
| } |
| } |