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17  package org.orekit.time;
18  
19  import org.junit.jupiter.api.Assertions;
20  import org.junit.jupiter.api.BeforeEach;
21  import org.junit.jupiter.api.Test;
22  import org.orekit.Utils;
23  import org.orekit.frames.ITRFVersion;
24  import org.orekit.utils.Constants;
25  import org.orekit.utils.IERSConventions;
26  
27  
28  public class TAIScaleTest {
29  
30      @Test
31      public void testZero() {
32          TimeScale scale = TimeScalesFactory.getTAI();
33          Assertions.assertEquals("TAI", scale.toString());
34          for (double dt = -10000; dt < 10000; dt += 123.456789) {
35              AbsoluteDate date = AbsoluteDate.J2000_EPOCH.shiftedBy(dt * Constants.JULIAN_DAY);
36              Assertions.assertEquals(0, scale.offsetFromTAI(date).toDouble(), 0);
37              DateTimeComponents components = date.getComponents(scale);
38              Assertions.assertEquals(0, scale.offsetToTAI(components.getDate(), components.getTime()).toDouble(), 0);
39          }
40      }
41  
42      @Test
43      public void testAAS06134() {
44  
45          // this reference test has been extracted from the following paper:
46          // Implementation Issues Surrounding the New IAU Reference Systems for Astrodynamics
47          // David A. Vallado, John H. Seago, P. Kenneth Seidelmann
48          // http://www.centerforspace.com/downloads/files/pubs/AAS-06-134.pdf
49          // Note that the dUT1 here is -0.439962, whereas it is -0.4399619 in the book
50          Utils.setLoaders(IERSConventions.IERS_1996,
51                           Utils.buildEOPList(IERSConventions.IERS_1996, ITRFVersion.ITRF_2008, new double[][] {
52                               { 53098, -0.439962, 0.0015563, -0.140682, 0.333309, -0.052195, -0.003875, Double.NaN, Double.NaN },
53                               { 53099, -0.439962, 0.0015563, -0.140682, 0.333309, -0.052195, -0.003875, Double.NaN, Double.NaN },
54                               { 53100, -0.439962, 0.0015563, -0.140682, 0.333309, -0.052195, -0.003875, Double.NaN, Double.NaN },
55                               { 53101, -0.439962, 0.0015563, -0.140682, 0.333309, -0.052195, -0.003875, Double.NaN, Double.NaN },
56                               { 53102, -0.439962, 0.0015563, -0.140682, 0.333309, -0.052195, -0.003875, Double.NaN, Double.NaN },
57                               { 53103, -0.439962, 0.0015563, -0.140682, 0.333309, -0.052195, -0.003875, Double.NaN, Double.NaN },
58                               { 53104, -0.439962, 0.0015563, -0.140682, 0.333309, -0.052195, -0.003875, Double.NaN, Double.NaN },
59                               { 53105, -0.439962, 0.0015563, -0.140682, 0.333309, -0.052195, -0.003875, Double.NaN, Double.NaN }
60                           }));
61          AbsoluteDate date =
62                  new AbsoluteDate(2004, 4, 6, 7, 51, 28.386009, TimeScalesFactory.getUTC());
63          DateTimeComponents components = date.getComponents(TimeScalesFactory.getTAI());
64          Assertions.assertEquals(2004,        components.getDate().getYear());
65          Assertions.assertEquals(   4,        components.getDate().getMonth());
66          Assertions.assertEquals(   6,        components.getDate().getDay());
67          Assertions.assertEquals(   7,        components.getTime().getHour());
68          Assertions.assertEquals(  52,        components.getTime().getMinute());
69          Assertions.assertEquals(   0.386009, components.getTime().getSecond(), 1.0e-10);
70      }
71  
72      @Test
73      public void testDuringLeap() {
74          final TimeScale utc   = TimeScalesFactory.getUTC();
75          final TimeScale scale = TimeScalesFactory.getTAI();
76          final AbsoluteDate before = new AbsoluteDate(new DateComponents(1983, 6, 30),
77                                                       new TimeComponents(23, 59, 59),
78                                                       utc);
79          final AbsoluteDate during = before.shiftedBy(1.25);
80          Assertions.assertEquals(61, utc.minuteDuration(during));
81          Assertions.assertEquals(1.0, utc.getLeap(during).toDouble(), 1.0e-10);
82          Assertions.assertEquals(60, scale.minuteDuration(during));
83          Assertions.assertEquals(0.0, scale.getLeap(during).toDouble(), 1.0e-10);
84      }
85  
86      @BeforeEach
87      public void setUp() {
88          Utils.setDataRoot("regular-data");
89      }
90  
91  }