public static SolarClock VedicShuddhi(SolarClock sc)
{
double solarArcTan = 0.53; //this is the diameter of the sun as see from the earth in degrees
double earthAngVelo = 0.25; //degrees per minute, this is the angular velocity of of the earth
double vedic_shudhi = (solarArcTan / 2) * earthAngVelo; //this is the correction when doin vedic calculations
sc.sunrise = sc.sunrise.AddMinutes(vedic_shudhi);
sc.sunset = sc.sunset.AddMinutes(-1 * vedic_shudhi);
return(sc);
}
public static SolarClock SolarClock(this DateTime dt, double latitude, double longitude,
double gmtoffset, bool atmRefrac)
{
SolarClock sc = new SolarClock();
sc.gregoriandate = dt;
//this is where we calcuclated the julian day, day index of the year
double n1 = Math.Floor((double)dt.Month * 275 / 9);
double n2 = Math.Floor((double)(dt.Month + 9) / 12);
double n3 = 1 + (Math.Floor((dt.Year - 4 * Math.Floor((double)dt.Year / 4) + 2) / 3));
sc.julian = (int)(n1 - (n2 * n3) + dt.Day - 30);
double B = ((double)(sc.julian - 81) * 360 / 365);
sc.declination = Algebric.SineInv(Algebric.Sine(23.45) * Algebric.Sine(B));
var lstm = 15 * gmtoffset; //local standard time meridian
var eot = 9.87 * (Algebric.Sine(2 * B)) - 7.53 * Algebric.Cosine(B) - 1.5 * Algebric.Sine(B); //equation of time
var tc = (4 * (longitude - lstm)) + eot; //total time correction in minutes
sc.noon = dt.AddHours(12 - (tc / 60));
var noonHourAngle = (tc / 60) * 15; //this is the time corection in degrees
//this is to consider the atmospheric refraction , but not all methods would consider atm refraction
//so this param is kept as conditional one
var refrac = atmRefrac == true?Algebric.Sine(-0.83) : 0;
var lngdecleffect = (refrac - (Algebric.Sine(sc.declination) * Algebric.Sine(latitude))) /
(Algebric.Cosine(sc.declination) * Algebric.Cosine(latitude));
var sunrise = 12 - (Algebric.CosineInv(lngdecleffect) / 15) - (tc / 60);
sc.sunrise = dt.AddHours(sunrise);
TimeSpan halfday = sc.noon.Subtract(sc.sunrise);
sc.sunset = sc.noon.AddHours(halfday.Hours).AddMinutes(halfday.Minutes).AddSeconds(halfday.Seconds);
sc.daylength = sc.sunset.Subtract(sc.sunrise);
return(sc);
}
