test

app/src/test/java/com/forrestguice/suntimeswidget/calculator/SunPositionTest.java

@@ -7,6 +7,7 @@
 import android.support.annotation.Nullable;
 
 import com.forrestguice.suntimeswidget.UnlistedTest;
+import com.forrestguice.suntimeswidget.calculator.core.SuntimesCalculator;
 
 import net.time4j.Moment;
 import net.time4j.PlainDate;
@@ -29,12 +30,12 @@ public class SunPositionTest
     /* Test Fix: add the geodetic angle before comparing elevations; brings twilight elevations into agreement with expected values. */
     public static final boolean APPLY_ALTITUDE_ANGLE = false;
 
-    public static final double TEST_TOLERANCE = 0.25;        // degrees
+    public static final double TEST_TOLERANCE = 0.01;        // degrees
     public static final double TEST_LATITUDE = 33.45579;
     public static final double TEST_LONGITUDE = -111.9485;    // Phoenix, AZ
     public static final int TEST_ALTITUDE = 360;
     public static final long TEST_DATE = 1639791526;         // Dec 17, 2021
-    public static final TimeZone TEST_TIMEZONE = TimeZone.getTimeZone("US/Arizona");
+    public static final TimeZone TEST_TIMEZONE = TimeZone.getTimeZone("UTC");
     public static final StdSolarCalculator TEST_CALCULATOR = StdSolarCalculator.TIME4J;
 
     @Before
@@ -45,6 +46,28 @@ public void setup() {
     private Calendar date = Calendar.getInstance();
     private SolarTime solarTime;
 
+    @Test
+    public void test_SunPosition()
+    {
+        Calendar date = Calendar.getInstance();
+        date.setTimeInMillis(1639791526);   // Dec 17, 2021
+        PlainDate plainDate = calendarToPlainDate(date, TimeZone.getTimeZone("UTC"));
+
+        Moment moment0 = TemporalType.JAVA_UTIL_DATE.translate(date.getTime());
+        net.time4j.calendar.astro.SunPosition position0 = net.time4j.calendar.astro.SunPosition.at(moment0, solarTime);
+        double elevation0 = position0.getElevation();
+
+        double geodeticAngle = TEST_CALCULATOR.getGeodeticAngle(TEST_LATITUDE, TEST_ALTITUDE);
+        double zenith = 90 + geodeticAngle - elevation0;
+
+        Moment moment1 = solarTime.getCalculator().sunrise(plainDate, TEST_LATITUDE, TEST_LONGITUDE, zenith);
+        net.time4j.calendar.astro.SunPosition position1 = net.time4j.calendar.astro.SunPosition.at(moment1, solarTime);
+        double elevation1 = position1.getElevation() + geodeticAngle;
+
+        assertTrue("expects value near " + elevation0 + " (within " + TEST_TOLERANCE + "); " + elevation1,
+                Math.abs(elevation0 - elevation1) < TEST_TOLERANCE);
+    }
+
     @Test
     public void test_sunPositionAtSunrise() {
         testElevationAtSunrise(date, solarTime, null, 0, TEST_TOLERANCE);

app/src/test/java/com/forrestguice/suntimeswidget/calculator/SunPositionTest1.java

@@ -0,0 +1,75 @@
+package com.forrestguice.suntimeswidget.calculator;
+
+import com.forrestguice.suntimeswidget.UnlistedTest;
+
+import net.time4j.Moment;
+import net.time4j.PlainDate;
+import net.time4j.TemporalType;
+import net.time4j.calendar.astro.SolarTime;
+import net.time4j.calendar.astro.StdSolarCalculator;
+import net.time4j.tz.ZonalOffset;
+
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+
+import java.util.Calendar;
+import java.util.GregorianCalendar;
+import java.util.TimeZone;
+
+import static org.junit.Assert.assertTrue;
+
+@Category(UnlistedTest.class)
+public class SunPositionTest1
+{
+    @Test
+    public void test_SunPosition()
+    {
+        // setup
+        double latitude = 33.45579;
+        double longitude = -111.9485;  // Phoenix, AZ
+        int altitude = 360;
+
+        TimeZone tz = TimeZone.getTimeZone("UTC");
+        Calendar date0 = Calendar.getInstance(tz);
+        date0.setTimeInMillis(1639791526);   // Dec 17, 2021
+        PlainDate plainDate = calendarToPlainDate(date0, tz);
+
+        SolarTime solarTime = SolarTime.ofLocation(latitude, longitude, altitude, StdSolarCalculator.TIME4J);
+        SolarTime.Calculator calculator = solarTime.getCalculator();
+
+        // find elevation at given date/time
+        Moment moment0 = TemporalType.JAVA_UTIL_DATE.translate(date0.getTime());
+        net.time4j.calendar.astro.SunPosition position0 = net.time4j.calendar.astro.SunPosition.at(moment0, solarTime);
+        double elevation0 = position0.getElevation();
+
+        // find date/time of given elevation
+        double geodeticAngle = StdSolarCalculator.TIME4J.getGeodeticAngle(latitude, altitude);
+        double zenith = 90 + geodeticAngle - elevation0;
+        Moment moment1 = calculator.sunset(plainDate, latitude, longitude, zenith);
+        Calendar date1 = momentToCalendar(moment1, tz);
+
+        double toleranceMs = 1 * 60 * 1000;    // 1min
+        long difference = date1.getTimeInMillis() - date0.getTimeInMillis();
+        assertTrue("expected time near " + date0.getTimeInMillis() + " (within " + (toleranceMs / (1000d * 60d)) + " min); " + date1.getTimeInMillis() + " differs by " + (difference / (1000d * 60d)) + " min",
+                Math.abs(difference) < toleranceMs);
+    }
+
+    public static Calendar momentToCalendar(Moment moment, TimeZone timezone)
+    {
+        Calendar retValue = null;
+        if (moment != null)
+        {
+            retValue = new GregorianCalendar();
+            retValue.setTimeZone(timezone);
+            retValue.setTime(TemporalType.JAVA_UTIL_DATE.from(moment));
+        }
+        return retValue;
+    }
+
+    public static PlainDate calendarToPlainDate(Calendar input, TimeZone timezone)
+    {
+        Moment moment = TemporalType.JAVA_UTIL_DATE.translate(input.getTime());
+        ZonalOffset zonalOffset = ZonalOffset.ofTotalSeconds(timezone.getOffset(input.getTimeInMillis()) / 1000);
+        return moment.toZonalTimestamp(zonalOffset).toDate();
+    }
+}