Coordinates/CoordinateSharp/Celestial.SunCalculations.cs

375 lines
15 KiB
C#

using System;
using System.Collections.Generic;
namespace CoordinateSharp
{
internal class SunCalc
{
public static void CalculateSunTime(double lat, double longi, DateTime date, Celestial c,double offset = 0)
{
if (date.Year == 0001) { return; } //Return if date vaue hasn't been established.
DateTime actualDate = new DateTime(date.Year,date.Month,date.Day,0, 0, 0, DateTimeKind.Utc);
////Sun Time Calculations
//Get Julian
double lw = rad * -longi;
double phi = rad * lat;
//Rise Set
DateTime?[] evDate = Get_Event_Time(lw, phi, -.8333, actualDate);
c.sunRise = evDate[0];
c.sunSet = evDate[1];
c.sunCondition = CelestialStatus.RiseAndSet;
//Azimuth and Altitude
CalculateSunAngle(date, longi, lat, c);
// neither sunrise nor sunset
if ((!c.SunRise.HasValue) && (!c.SunSet.HasValue))
{
if (c.SunAltitude < 0)
{
c.sunCondition = CelestialStatus.DownAllDay;
}
else
{
c.sunCondition = CelestialStatus.UpAllDay;
}
}
// sunrise or sunset
else
{
if (!c.SunRise.HasValue)
{
// No sunrise this date
c.sunCondition = CelestialStatus.NoRise;
}
else if (!c.SunSet.HasValue)
{
// No sunset this date
c.sunCondition = CelestialStatus.NoSet;
}
}
//Additional Times
c.additionalSolarTimes = new AdditionalSolarTimes();
//Dusk and Dawn
//Civil
evDate = Get_Event_Time(lw, phi, -6, actualDate);
c.AdditionalSolarTimes.CivilDawn = evDate[0];
c.AdditionalSolarTimes.CivilDusk = evDate[1];
//Nautical
evDate = Get_Event_Time(lw, phi, -12, actualDate);
c.AdditionalSolarTimes.NauticalDawn = evDate[0];
c.AdditionalSolarTimes.NauticalDusk = evDate[1];
//Astronomical
evDate = Get_Event_Time(lw, phi, -18, actualDate);
c.AdditionalSolarTimes.AstronomicalDawn = evDate[0];
c.AdditionalSolarTimes.AstronomicalDusk = evDate[1];
//BottomDisc
evDate = Get_Event_Time(lw, phi, -.2998, actualDate);
c.AdditionalSolarTimes.SunriseBottomDisc = evDate[0];
c.AdditionalSolarTimes.SunsetBottomDisc = evDate[1];
CalculateSolarEclipse(date, lat, longi, c);
}
/// <summary>
/// Gets time of event based on specified degree below horizon
/// </summary>
/// <param name="lw">Observer Longitude in radians</param>
/// <param name="phi">Observer Latitude in radians</param>
/// <param name="h">Angle in Degrees</param>
/// <param name="date">Date of Event</param>
/// <returns>DateTime?[]{rise, set}</returns>
private static DateTime?[] Get_Event_Time(double lw, double phi, double h,DateTime date)
{
//Create arrays. Index 0 = Day -1, 1 = Day, 2 = Day + 1;
//These will be used to find exact day event occurs for comparison
DateTime?[] sets = new DateTime?[] { null, null, null, null, null };
DateTime?[] rises = new DateTime?[] { null, null, null,null, null };
//Iterate starting with day -1;
for (int x = 0; x < 5; x++)
{
double d = JulianConversions.GetJulian(date.AddDays(x-2)) - j2000 + .5; //LESS PRECISE JULIAN NEEDED
double n = julianCycle(d, lw);
double ds = approxTransit(0, lw, n);
double M = solarMeanAnomaly(ds);
double L = eclipticLongitude(M);
double dec = declination(L, 0);
double Jnoon = solarTransitJ(ds, M, L);
double Jset;
double Jrise;
DateTime? solarNoon = JulianConversions.GetDate_FromJulian(Jnoon);
DateTime? nadir = JulianConversions.GetDate_FromJulian(Jnoon - 0.5);
//Rise Set
Jset = GetTime(h * rad, lw, phi, dec, n, M, L);
Jrise = Jnoon - (Jset - Jnoon);
DateTime? rise = JulianConversions.GetDate_FromJulian(Jrise);
DateTime? set = JulianConversions.GetDate_FromJulian(Jset);
rises[x] = rise;
sets[x] = set;
}
//Compare and send
DateTime? tRise = null;
for(int x=0;x<5;x++)
{
if(rises[x].HasValue)
{
if(rises[x].Value.Day == date.Day)
{
tRise = rises[x];
break;
}
}
}
DateTime? tSet = null;
for (int x = 0; x < 5; x++)
{
if (sets[x].HasValue)
{
if (sets[x].Value.Day == date.Day)
{
tSet = sets[x];
break;
}
}
}
return new DateTime?[] { tRise, tSet };
}
public static void CalculateZodiacSign(DateTime date, Celestial c)
{
//Aquarius (January 20 to February 18)
//Pisces (February 19 to March 20)
//Aries (March 21-April 19)
//Taurus (April 20-May 20)
//Gemini (May 21-June 20)
//Cancer (June 21-July 22)
//Leo (July 23-August 22)
//Virgo (August 23-September 22)
//Libra (September 23-October 22)
//Scorpio (October 23-November 21)
//Sagittarius (November 22-December 21)
//Capricorn (December 22-January 19)
if (date >= new DateTime(date.Year, 1, 1) && date <= new DateTime(date.Year, 1, 19, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Capricorn";
return;
}
if (date >= new DateTime(date.Year, 1, 20) && date <= new DateTime(date.Year, 2, 18, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Aquarius";
return;
}
if (date >= new DateTime(date.Year, 2, 19) && date <= new DateTime(date.Year, 3, 20, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Pisces";
return;
}
if (date >= new DateTime(date.Year, 3, 21) && date <= new DateTime(date.Year, 4, 19, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Aries";
return;
}
if (date >= new DateTime(date.Year, 4, 20) && date <= new DateTime(date.Year, 5, 20, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Taurus";
return;
}
if (date >= new DateTime(date.Year, 5, 21) && date <= new DateTime(date.Year, 6, 20,23,59,59))
{
c.AstrologicalSigns.ZodiacSign = "Gemini";
return;
}
if (date >= new DateTime(date.Year, 6, 21) && date <= new DateTime(date.Year, 7, 22, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Cancer";
return;
}
if (date >= new DateTime(date.Year, 7, 23) && date <= new DateTime(date.Year, 8, 22, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Leo";
return;
}
if (date >= new DateTime(date.Year, 8, 23) && date <= new DateTime(date.Year, 9, 22, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Virgo";
return;
}
if (date >= new DateTime(date.Year, 9, 23) && date <= new DateTime(date.Year, 10, 22, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Libra";
return;
}
if (date >= new DateTime(date.Year, 9, 23) && date <= new DateTime(date.Year, 11, 21, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Scorpio";
return;
}
if (date >= new DateTime(date.Year, 11, 21) && date <= new DateTime(date.Year, 12, 21, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Sagittarius";
return;
}
if (date >= new DateTime(date.Year, 12, 22) && date <= new DateTime(date.Year, 12, 31, 23, 59, 59))
{
c.AstrologicalSigns.ZodiacSign = "Capricorn";
return;
}
}
public static void CalculateSolarEclipse(DateTime date, double lat, double longi, Celestial c)
{
//Convert to Radian
double latR = lat * Math.PI / 180;
double longR = longi * Math.PI / 180;
List<List<string>> se = SolarEclipseCalc.CalculateSolarEclipse(date, latR, longR);
//RETURN FIRST AND LAST
if (se.Count == 0) { return; }
//FIND LAST AND NEXT ECLIPSE
int lastE = -1;
int nextE = -1;
int currentE = 0;
DateTime lastDate = new DateTime();
DateTime nextDate = new DateTime(3300, 1, 1);
//Iterate to get last and next eclipse
foreach(List<string> values in se)
{
DateTime ld = DateTime.ParseExact(values[0], "yyyy-MMM-dd", System.Globalization.CultureInfo.InvariantCulture);
if (ld < date && ld>lastDate) { lastDate = ld;lastE = currentE; }
if(ld>= date && ld < nextDate) { nextDate = ld;nextE = currentE; }
currentE++;
}
//SET ECLIPSE DATA
if (lastE >= 0)
{
c.SolarEclipse.LastEclipse = new SolarEclipseDetails(se[lastE]);
}
if (nextE >= 0)
{
c.SolarEclipse.NextEclipse = new SolarEclipseDetails(se[nextE]);
}
}
#region Private Suntime Members
private static readonly double dayMS = 1000 * 60 * 60 * 24, j1970 = 2440588, j2000 = 2451545;
private static readonly double rad = Math.PI / 180;
private static double LocalSiderealTimeForTimeZone(double lon, double jd, double z)
{
double s = 24110.5 + 8640184.812999999 * jd / 36525 + 86636.6 * z + 86400 * lon;
s = s / 86400;
s = s - Math.Truncate(s);
double lst = s * 360 *rad;
return lst;
}
private static double SideRealTime(double d, double lw)
{
double s = rad * (280.16 + 360.9856235 * d) - lw;
return s;
}
private static double solarTransitJ(double ds, double M, double L)
{
return j2000 + ds + 0.0053 * Math.Sin(M) - 0.0069 * Math.Sin(2 * L);
}
//CH15
//Formula 15.1
//Returns Approximate Time
private static double hourAngle(double h, double phi, double d)
{
//NUMBER RETURNING > and < 1 NaN;
double d1 = Math.Sin(h) - Math.Sin(phi) * Math.Sin(d);
double d2 = Math.Cos(phi) * Math.Cos(d);
double d3 = (d1 / d2);
return Math.Acos(d3);
}
private static double approxTransit(double Ht, double lw, double n)
{
return 0.0009 + (Ht + lw) / (2 * Math.PI) + n;
}
private static double julianCycle(double d, double lw) { return Math.Round(d - 0.0009 - lw / (2 * Math.PI)); }
//Returns Time of specified event based on suns angle
private static double GetTime(double h, double lw, double phi, double dec, double n,double M, double L)
{
double approxTime = hourAngle(h, phi, dec); //Ch15 Formula 15.1
double a = approxTransit(approxTime, lw, n);
double st = solarTransitJ(a, M, L);
return st;
}
private static double declination(double l, double b)
{
double e = (Math.PI/180) * 23.4392911; // obliquity of the Earth
return Math.Asin(Math.Sin(b) * Math.Cos(e) + Math.Cos(b) * Math.Sin(e) * Math.Sin(l));
}
private static void CalculateSunAngle(DateTime date, double longi, double lat, Celestial c)
{
TimeSpan ts = date - new DateTime(1970, 1, 1,0,0,0, DateTimeKind.Utc);
double dms = (ts.TotalMilliseconds / dayMS -.5 + j1970)-j2000;
double lw = rad * -longi;
double phi = rad * lat;
double e = rad * 23.4397;
double[] sc = sunCoords(dms);
double H = SideRealTime(dms, lw) - sc[1];
c.sunAzimuth = Math.Atan2(Math.Sin(H), Math.Cos(H) * Math.Sin(phi) - Math.Tan(sc[0]) * Math.Cos(phi)) * 180 / Math.PI + 180;
c.sunAltitude = Math.Asin(Math.Sin(phi) * Math.Sin(sc[0]) + Math.Cos(phi) * Math.Cos(sc[0]) * Math.Cos(H)) * 180 / Math.PI;
}
private static double solarMeanAnomaly(double d)
{
return rad * (357.5291 + 0.98560028 * d);
}
private static double eclipticLongitude(double m)
{
double c = rad * (1.9148 * Math.Sin(m) + 0.02 * Math.Sin(2 * m) + 0.0003 * Math.Sin(3 * m)); // equation of center
double p = rad * 102.9372; // perihelion of the Earth
return m + c + p + Math.PI;
}
private static double[] sunCoords(double d)
{
double m = solarMeanAnomaly(d);
double l = eclipticLongitude(m);
double[] sc = new double[2];
double b = 0;
double e = rad * 23.4397; // obliquity of the Earth
sc[0] = Math.Asin(Math.Sin(b) * Math.Cos(e) + Math.Cos(b) * Math.Sin(e) * Math.Sin(l)); //declination
sc[1] = Math.Atan2(Math.Sin(l) * Math.Cos(e) - Math.Tan(b) * Math.Sin(e), Math.Cos(l)); //rightAscension
return sc;
}
#endregion
}
}