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More code simlification and refactoring of NOAACalculator
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No impact to any public interfaces.
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@KosherJava
KosherJava authored Jul 14, 2024
1 parent 524e848 commit 63403fd
Showing 1 changed file with 39 additions and 51 deletions.
90 changes: 39 additions & 51 deletions src/main/java/com/kosherjava/zmanim/util/NOAACalculator.java
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Original file line number Diff line number Diff line change
Expand Up @@ -65,7 +65,7 @@ public String getCalculatorName() {
public double getUTCSunrise(Calendar calendar, GeoLocation geoLocation, double zenith, boolean adjustForElevation) {
double elevation = adjustForElevation ? geoLocation.getElevation() : 0;
double adjustedZenith = adjustZenith(zenith, elevation);
double sunrise = getSunRiseSetUTC(getJulianDay(calendar), geoLocation.getLatitude(), -geoLocation.getLongitude(),
double sunrise = getSunRiseSetUTC(calendar, geoLocation.getLatitude(), -geoLocation.getLongitude(),
adjustedZenith, SolarEvent.SUNRISE);
sunrise = sunrise / 60;
return sunrise > 0 ? sunrise % 24 : sunrise % 24 + 24; // ensure that the time is >= 0 and < 24
Expand All @@ -77,7 +77,7 @@ public double getUTCSunrise(Calendar calendar, GeoLocation geoLocation, double z
public double getUTCSunset(Calendar calendar, GeoLocation geoLocation, double zenith, boolean adjustForElevation) {
double elevation = adjustForElevation ? geoLocation.getElevation() : 0;
double adjustedZenith = adjustZenith(zenith, elevation);
double sunset = getSunRiseSetUTC(getJulianDay(calendar), geoLocation.getLatitude(), -geoLocation.getLongitude(),
double sunset = getSunRiseSetUTC(calendar, geoLocation.getLatitude(), -geoLocation.getLongitude(),
adjustedZenith, SolarEvent.SUNSET);
sunset = sunset / 60;
return sunset > 0 ? sunset % 24 : sunset % 24 + 24; // ensure that the time is >= 0 and < 24
Expand Down Expand Up @@ -116,19 +116,6 @@ private static double getJulianCenturiesFromJulianDay(double julianDay) {
return (julianDay - JULIAN_DAY_JAN_1_2000) / JULIAN_DAYS_PER_CENTURY;
}

/**
* Convert centuries since <a href="https://en.wikipedia.org/wiki/Epoch_(astronomy)#J2000">J2000.0</a> to
* <a href="https://en.wikipedia.org/wiki/Julian_day">Julian day</a>.
*
* @param julianCenturies
* the number of Julian centuries since <a href=
* "https://en.wikipedia.org/wiki/Epoch_(astronomy)#J2000">J2000.0</a>.
* @return the Julian Day corresponding to the Julian centuries passed in
*/
private static double getJulianDayFromJulianCenturies(double julianCenturies) {
return julianCenturies * JULIAN_DAYS_PER_CENTURY + JULIAN_DAY_JAN_1_2000;
}

/**
* Returns the Geometric <a href="https://en.wikipedia.org/wiki/Mean_longitude">Mean Longitude</a> of the Sun.
*
Expand All @@ -143,31 +130,31 @@ private static double getSunGeometricMeanLongitude(double julianCenturies) {
}

/**
* Returns the Geometric <a href="https://en.wikipedia.org/wiki/Mean_anomaly">Mean Anomaly</a> of the Sun.
* Returns the Geometric <a href="https://en.wikipedia.org/wiki/Mean_anomaly">Mean Anomaly</a> of the Sun in degrees.
*
* @param julianCenturies
* the number of Julian centuries since <a href=
* "https://en.wikipedia.org/wiki/Epoch_(astronomy)#J2000">J2000.0</a>.
* @return the Geometric Mean Anomaly of the Sun in degrees
*/
private static double getSunGeometricMeanAnomaly(double julianCenturies) {
return 357.52911 + julianCenturies * (35999.05029 - 0.0001537 * julianCenturies); // in degrees
return 357.52911 + julianCenturies * (35999.05029 - 0.0001537 * julianCenturies);
}

/**
* Return the <a href="https://en.wikipedia.org/wiki/Eccentricity_%28orbit%29">eccentricity of earth's orbit</a>.
* Return the unitless <a href="https://en.wikipedia.org/wiki/Eccentricity_%28orbit%29">eccentricity of earth's orbit</a>.
*
* @param julianCenturies
* the number of Julian centuries since <a href=
* "https://en.wikipedia.org/wiki/Epoch_(astronomy)#J2000">J2000.0</a>.
* @return the unitless eccentricity
*/
private static double getEarthOrbitEccentricity(double julianCenturies) {
return 0.016708634 - julianCenturies * (0.000042037 + 0.0000001267 * julianCenturies); // unitless
return 0.016708634 - julianCenturies * (0.000042037 + 0.0000001267 * julianCenturies);
}

/**
* Returns the <a href="https://en.wikipedia.org/wiki/Equation_of_the_center">equation of center</a> for the sun.
* Returns the <a href="https://en.wikipedia.org/wiki/Equation_of_the_center">equation of center</a> for the sun in degrees.
*
* @param julianCenturies
* the number of Julian centuries since <a href=
Expand All @@ -181,7 +168,7 @@ private static double getSunEquationOfCenter(double julianCenturies) {
double sin2m = Math.sin(mrad + mrad);
double sin3m = Math.sin(mrad + mrad + mrad);
return sinm * (1.914602 - julianCenturies * (0.004817 + 0.000014 * julianCenturies)) + sin2m
* (0.019993 - 0.000101 * julianCenturies) + sin3m * 0.000289; // in degrees
* (0.019993 - 0.000101 * julianCenturies) + sin3m * 0.000289;
}

/**
Expand All @@ -195,7 +182,7 @@ private static double getSunEquationOfCenter(double julianCenturies) {
private static double getSunTrueLongitude(double julianCenturies) {
double sunLongitude = getSunGeometricMeanLongitude(julianCenturies);
double center = getSunEquationOfCenter(julianCenturies);
return sunLongitude + center; // in degrees
return sunLongitude + center;
}

// /**
Expand All @@ -209,7 +196,7 @@ private static double getSunTrueLongitude(double julianCenturies) {
// double meanAnomaly = getSunGeometricMeanAnomaly(julianCenturies);
// double equationOfCenter = getSunEquationOfCenter(julianCenturies);
//
// return meanAnomaly + equationOfCenter; // in degrees
// return meanAnomaly + equationOfCenter;
// }

/**
Expand All @@ -224,7 +211,7 @@ private static double getSunApparentLongitude(double julianCenturies) {
double sunTrueLongitude = getSunTrueLongitude(julianCenturies);
double omega = 125.04 - 1934.136 * julianCenturies;
double lambda = sunTrueLongitude - 0.00569 - 0.00478 * Math.sin(Math.toRadians(omega));
return lambda; // in degrees
return lambda;
}

/**
Expand All @@ -238,7 +225,7 @@ private static double getSunApparentLongitude(double julianCenturies) {
private static double getMeanObliquityOfEcliptic(double julianCenturies) {
double seconds = 21.448 - julianCenturies
* (46.8150 + julianCenturies * (0.00059 - julianCenturies * (0.001813)));
return 23.0 + (26.0 + (seconds / 60.0)) / 60.0; // in degrees
return 23.0 + (26.0 + (seconds / 60.0)) / 60.0;
}

/**
Expand All @@ -253,7 +240,7 @@ private static double getMeanObliquityOfEcliptic(double julianCenturies) {
private static double getObliquityCorrection(double julianCenturies) {
double obliquityOfEcliptic = getMeanObliquityOfEcliptic(julianCenturies);
double omega = 125.04 - 1934.136 * julianCenturies;
return obliquityOfEcliptic + 0.00256 * Math.cos(Math.toRadians(omega)); // in degrees
return obliquityOfEcliptic + 0.00256 * Math.cos(Math.toRadians(omega));
}

/**
Expand All @@ -270,7 +257,7 @@ private static double getSunDeclination(double julianCenturies) {
double lambda = getSunApparentLongitude(julianCenturies);
double sint = Math.sin(Math.toRadians(obliquityCorrection)) * Math.sin(Math.toRadians(lambda));
double theta = Math.toDegrees(Math.asin(sint));
return theta; // in degrees
return theta;
}

/**
Expand All @@ -296,7 +283,7 @@ private static double getEquationOfTime(double julianCenturies) {
double sin2m = Math.sin(2.0 * Math.toRadians(geomMeanAnomalySun));
double equationOfTime = y * sin2l0 - 2.0 * eccentricityEarthOrbit * sinm + 4.0 * eccentricityEarthOrbit * y
* sinm * cos2l0 - 0.5 * y * y * sin4l0 - 1.25 * eccentricityEarthOrbit * eccentricityEarthOrbit * sin2m;
return Math.toDegrees(equationOfTime) * 4.0; // in minutes of time
return Math.toDegrees(equationOfTime) * 4.0;
}

/**
Expand Down Expand Up @@ -403,20 +390,19 @@ public static double getSolarAzimuth(Calendar calendar, double latitude, double
* @return the time in minutes from zero UTC
*/
public double getUTCNoon(Calendar calendar, GeoLocation geoLocation) {
double julianDay = getJulianDay(calendar);
double julianCenturies = getJulianCenturiesFromJulianDay(julianDay);
double noon = getSolarNoonUTC(julianCenturies, -geoLocation.getLongitude());
double noon = getSolarNoonUTC(getJulianDay(calendar), -geoLocation.getLongitude());
noon = noon / 60;
return noon > 0 ? noon % 24 : noon % 24 + 24; // ensure that the time is >= 0 and < 24
}

/**
* Return the <a href="https://en.wikipedia.org/wiki/Universal_Coordinated_Time">Universal Coordinated Time</a> (UTC)
* of of <a href="http://en.wikipedia.org/wiki/Noon#Solar_noon">solar noon</a> for the given day at the given location
* of <a href="http://en.wikipedia.org/wiki/Noon#Solar_noon">solar noon</a> for the given day at the given location
* on earth.
* @todo Refactor to possibly use the getSunRiseSetUTC (to be renamed) and remove the need for this method.
*
* @param julianCenturies
* the number of Julian centuries since <a href=
* @param julianDay
* the Julian day since <a href=
* "https://en.wikipedia.org/wiki/Epoch_(astronomy)#J2000">J2000.0</a>.
* @param longitude
* the longitude of observer in degrees
Expand All @@ -426,24 +412,26 @@ public double getUTCNoon(Calendar calendar, GeoLocation geoLocation) {
* @see com.kosherjava.zmanim.util.AstronomicalCalculator#getUTCNoon(Calendar, GeoLocation)
* @see #getUTCNoon(Calendar, GeoLocation)
*/
private static double getSolarNoonUTC(double julianCenturies, double longitude) {
// Only 1 pass for approximate solar noon to calculate equation of time
double tnoon = getJulianCenturiesFromJulianDay(getJulianDayFromJulianCenturies(julianCenturies) + longitude
/ 360.0);
private static double getSolarNoonUTC(double julianDay, double longitude) {
// First pass for approximate solar noon to calculate equation of time
double tnoon = getJulianCenturiesFromJulianDay(julianDay + longitude / 360.0);
double equationOfTime = getEquationOfTime(tnoon);
double solNoonUTC = 720 + (longitude * 4) - equationOfTime; // minutes
double newt = getJulianCenturiesFromJulianDay(getJulianDayFromJulianCenturies(julianCenturies) - 0.5
+ solNoonUTC / 1440.0);

// second pass
double newt = getJulianCenturiesFromJulianDay(julianDay - 0.5 + solNoonUTC / 1440.0);
equationOfTime = getEquationOfTime(newt);
return 720 + (longitude * 4) - equationOfTime; // minutes
return 720 + (longitude * 4) - equationOfTime;
}

/**
* Return the <a href="https://en.wikipedia.org/wiki/Universal_Coordinated_Time">Universal Coordinated Time</a> (UTC)
* of sunrise or sunset for the given day at the given location on earth.
* of sunrise or sunset in minutes for the given day at the given location on earth.
* @todo support solar noon and possibly increase the number of passes in the Arctic areas.
* This would remove the need for getSolarNoonUTC.
*
* @param julianDay
* the Julian day
* @param calendar
* the calendar
* @param latitude
* the latitude of observer in degrees
* @param longitude
Expand All @@ -454,16 +442,16 @@ private static double getSolarNoonUTC(double julianCenturies, double longitude)
* Is the calculation for sunrise or sunset
* @return the time in minutes from zero Universal Coordinated Time (UTC)
*/
private static double getSunRiseSetUTC(double julianDay, double latitude, double longitude, double zenith,
private static double getSunRiseSetUTC(Calendar calendar, double latitude, double longitude, double zenith,
SolarEvent solarEvent) {
double julianCenturies = getJulianCenturiesFromJulianDay(julianDay);
double julianDay = getJulianDay(calendar);

// Find the time of solar noon at the location, and use that declination.
// This is better than start of the Julian day
double noonmin = getSolarNoonUTC(julianCenturies, longitude);
double noonmin = getSolarNoonUTC(julianDay, longitude);
double tnoon = getJulianCenturiesFromJulianDay(julianDay + noonmin / 1440.0);

// First calculates sunrise and approx length of day
// First calculates sunrise and approximate length of day
double equationOfTime = getEquationOfTime(tnoon);
double solarDeclination = getSunDeclination(tnoon);
double hourAngle = getSunHourAngle(latitude, solarDeclination, zenith, solarEvent);
Expand All @@ -472,14 +460,14 @@ private static double getSunRiseSetUTC(double julianDay, double latitude, double
double timeUTC = 720 + timeDiff - equationOfTime;

// Second pass includes fractional Julian Day in gamma calc
double newt = getJulianCenturiesFromJulianDay(getJulianDayFromJulianCenturies(julianCenturies) + timeUTC
/ 1440.0);
double newt = getJulianCenturiesFromJulianDay(julianDay + timeUTC / 1440.0);
equationOfTime = getEquationOfTime(newt);

solarDeclination = getSunDeclination(newt);
hourAngle = getSunHourAngle(latitude, solarDeclination, zenith, solarEvent);
delta = longitude - Math.toDegrees(hourAngle);
timeDiff = 4 * delta;
timeUTC = 720 + timeDiff - equationOfTime; // in minutes
timeUTC = 720 + timeDiff - equationOfTime;
return timeUTC;
}
}

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