1 /* 2 * Copyright (C) 2009 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.hardware.cts; 18 19 import android.hardware.GeomagneticField; 20 import android.platform.test.annotations.Presubmit; 21 import android.test.AndroidTestCase; 22 23 import java.util.GregorianCalendar; 24 25 public class GeomagneticFieldTest extends AndroidTestCase { 26 private static final float DECLINATION_THRESHOLD = 0.1f; 27 private static final float INCLINATION_THRESHOLD = 0.1f; 28 private static final float FIELD_STRENGTH_THRESHOLD = 100; 29 30 @Presubmit 31 public void testGeomagneticField() { 32 // Reference values calculated from NOAA online calculator for WMM 2015 33 // https://www.ngdc.noaa.gov/geomag-web/#igrfwmm 34 TestDataPoint testPoints[] = new TestDataPoint[] { 35 // Mountain View, CA, USA on 2017/1/1 36 new TestDataPoint(37.386f, -122.083f, 32, 2017, 1, 1, 37 13.4589f, 60.9542f, 48168.0f), 38 // Chengdu, China on 2017/8/8 39 new TestDataPoint(30.658f, 103.935f, 500f, 2017, 8, 8, 40 -1.9784f, 47.9723f, 50717.3f), 41 // Sao Paulo, Brazil on 2018/12/25 42 new TestDataPoint(-23.682f, -46.875f, 760f, 2018, 12, 25, 43 -21.3130f, -37.9940f, 22832.3f), 44 // Boston, MA, USA on 2019/2/10 45 new TestDataPoint(42.313f, -71.127f, 43f, 2019, 2, 10, 46 -14.5391f, 66.9693f, 51815.1f), 47 // Cape Town, South Africa on 2019/5/1 48 new TestDataPoint(-33.913f, 18.095f, 100f, 2019, 5, 1, 49 -25.2454f, -65.8887f, 25369.2f), 50 // Sydney, Australia on 2020/1/1 51 new TestDataPoint(-33.847f, 150.791f, 19f, 2020, 1, 1, 52 12.4469f, -64.3443f, 57087.9f) 53 }; 54 55 for (TestDataPoint t : testPoints) { 56 GeomagneticField field = 57 new GeomagneticField(t.latitude, t.longitude, t.altitude, t.epochTimeMillis); 58 assertEquals(t.declinationDegree, field.getDeclination(), DECLINATION_THRESHOLD); 59 assertEquals(t.inclinationDegree, field.getInclination(), INCLINATION_THRESHOLD); 60 assertEquals(t.fieldStrengthNanoTesla, field.getFieldStrength(), 61 FIELD_STRENGTH_THRESHOLD); 62 63 float horizontalFieldStrengthNanoTesla = (float)( 64 Math.cos(Math.toRadians(t.inclinationDegree)) * t.fieldStrengthNanoTesla); 65 assertEquals(horizontalFieldStrengthNanoTesla, field.getHorizontalStrength(), 66 FIELD_STRENGTH_THRESHOLD); 67 68 float verticalFieldStrengthNanoTesla = (float)( 69 Math.sin(Math.toRadians(t.inclinationDegree)) * t.fieldStrengthNanoTesla); 70 assertEquals(verticalFieldStrengthNanoTesla, field.getZ(), FIELD_STRENGTH_THRESHOLD); 71 72 float declinationDegree = (float)( 73 Math.toDegrees(Math.atan2(field.getY(), field.getX()))); 74 assertEquals(t.declinationDegree, declinationDegree, DECLINATION_THRESHOLD); 75 assertEquals(horizontalFieldStrengthNanoTesla, 76 Math.sqrt(field.getX() * field.getX() + field.getY() * field.getY()), 77 FIELD_STRENGTH_THRESHOLD); 78 } 79 } 80 81 private class TestDataPoint { 82 public final float latitude; 83 public final float longitude; 84 public final float altitude; 85 public final long epochTimeMillis; 86 public final float declinationDegree; 87 public final float inclinationDegree; 88 public final float fieldStrengthNanoTesla; 89 90 TestDataPoint(float lat, float lng, float alt, int year, int month, int day, 91 float dec, float inc, float strength) { 92 latitude = lat; 93 longitude = lng; 94 altitude = alt; 95 epochTimeMillis = new GregorianCalendar(year, month, day).getTimeInMillis(); 96 declinationDegree = dec; 97 inclinationDegree = inc; 98 fieldStrengthNanoTesla = strength; 99 } 100 } 101 } 102
