private void GraphAltitude(DateTime gStart, DateTime gEnd, Celestial.RADec gRaDec, Celestial.LatLon gloc, string gName, Color gcolor)
{
//Graph the altitude change on 10 min intervals between gstart and gend for the position gRaDec for th observer at location gloc
const int gPoints = 60; //number of points to graph
double gInterval = (gEnd - gStart).TotalHours / gPoints;
DateTime gTime = gStart;
while (gTime <= gEnd)
{
double haR = gRaDec.HourAngle(gTime, gloc);
double haH = Transform.RadiansToHours(haR);
double altR = gRaDec.Altitude(haR, gloc);
double altitude = Transform.RadiansToDegrees(altR);
//
double gst = Celestial.DateUTCToGST(gTime);
double lst = Celestial.GSTToLST(gst, gloc.Lon);
//
if (altitude > 0)
{
DateTime localTime = gTime.ToLocalTime();
AltitudeChart.Series[gName].Points.AddXY(localTime, altitude);
}
//If (TargetControl.IsMoonUp(ImageForecastForm.tgtdata, ImageForecastForm.moondata, gTime))) Then
// AltitudeChart.Series("AltitudePath").Points.
gTime = gTime.AddHours(gInterval);
}
return;
}
private double ComputeAltitude(DateTime timeLocal, double RAHours, double DecDegrees, double latitudeDegrees, double longitudeDegrees)
// Returns maximum altitude for object at RA/Dec between times dusk and dawn
{
Celestial.LatLon location = new Celestial.LatLon(Transform.DegreesToRadians(latitudeDegrees), Transform.DegreesToRadians(longitudeDegrees));
Celestial.RADec position = new Celestial.RADec(Transform.HoursToRadians(RAHours), Transform.DegreesToRadians(DecDegrees));
double maxAlt = Transform.RadiansToDegrees(position.Altitude((position.HourAngle(timeLocal.ToUniversalTime(), location)), location));
return(maxAlt);
}
public DailyPosition(DateTime utcdateStart, DateTime utcdateEnd, Celestial.RADec tradec, Celestial.LatLon tlatlon, double tminAlt)
{
//utcdate as utc date (datetime)
//tradec as position of tar{ get { (RADec)
//tlatlon as location of observer (LatLon)
//minAlt as minimum horizon (degrees): negative is below horizon, positive is above horizon
bool AboveToStart;
bool rise;
bool sett;
t_state = VisibilityState.UpSome;
t_moonfree = 0;
t_moonphase = 0;
double thour;
double utriseH = 0;
double utsetH = 0;
double yminus, yzero, yplus;
Planar.QuadRoot solve;
double sinMinAltD = Transform.SinD(tminAlt); //Rise at h = 0 arcminutes
DateTime udate = utcdateStart;
rise = false;
sett = false;
AboveToStart = false;
thour = 1;
double altitude = tradec.Altitude(tradec.HourAngle(udate.AddHours(thour - 1), tlatlon), tlatlon);
yminus = Math.Sin(tradec.Altitude(tradec.HourAngle(udate.AddHours(thour - 1), tlatlon), tlatlon)) - sinMinAltD;
if (yminus > 0)
{
AboveToStart = true;
}
do
{
yzero = Math.Sin(tradec.Altitude(tradec.HourAngle(udate.AddHours(thour), tlatlon), tlatlon)) - sinMinAltD;
yplus = Math.Sin(tradec.Altitude(tradec.HourAngle(udate.AddHours(thour + 1), tlatlon), tlatlon)) - sinMinAltD;
solve = Planar.Quad(yminus, yzero, yplus);
switch (solve.nz)
{
case 0:
break;
case 1:
if (yminus < 0)
{
utriseH = thour + solve.zero1;
rise = true;
}
else
{
utsetH = thour + solve.zero1;
sett = true;
}
break;
case 2:
if (solve.ye < 0)
{
utriseH = thour + solve.zero2;
utsetH = thour + solve.zero1;
}
else
{
utriseH = thour + solve.zero1;
utsetH = thour + solve.zero2;
}
rise = true;
sett = true;
break;
}
yminus = yplus;
thour = thour + 2;
}while (!((thour == 25) || (rise && sett) || (utcdateStart.AddHours(thour + 1) > utcdateEnd)));
t_utcdate = utcdateStart;
t_position = tradec;
t_location = tlatlon;
t_minalt = tminAlt;
i_rise = utcdateStart;
i_set = utcdateEnd;
//Condition abovetostart and rise or not abovetostart and sett cannot occur (at least on paper)
if (AboveToStart && (!(rise || sett)))
{
//Tar{ get { path is always above minimum altitude (e.g. horizon)
t_state = VisibilityState.UpAlways;
t_rise = utcdateStart;
t_set = utcdateEnd;
}
else if ((!AboveToStart) && (rise && (!sett)))
{
//Tar{ get { path starts below) { ascends above minimum altitude (e.g. horizon)
t_state = VisibilityState.Rises;
t_rise = udate.AddHours(utriseH);
t_set = utcdateEnd;
//if (t_rise > t_set) {
// t_set = t_set.AddDays(1)
//}
}
else if (AboveToStart && ((!rise) && sett))
{
//Tar{ get { path starts above) { decends below minimum altitude (e.g. horizon)
t_state = VisibilityState.Falls;
t_rise = utcdateStart;
t_set = udate.AddHours(utsetH);
if (t_rise > t_set)
{
t_set = t_set.AddDays(1);
}
}
else if (AboveToStart && (rise && sett))
{
//Tar{ get { path decends below) { rises above minimum altitude (e.g. horizon)
//Choose the longer of the two rise/set intervals
t_state = VisibilityState.DownSome;
t_rise = udate.AddHours(utriseH);
t_set = udate.AddHours(utsetH);
if ((t_set - i_rise) > (i_set - t_rise))
{
t_rise = i_rise;
}
else
{
t_set = i_set;
}
//rise should be after set
//if (t_rise < t_set) {
// t_rise += TimeSpan.FromDays(1)
//}
}
else
{
if ((!AboveToStart) && (rise && sett))
{
//Tar{ get { path rises above) { decends below minimum altitude (e.g. horizon)
//Save the
t_state = VisibilityState.UpSome;
t_rise = udate.AddHours(utriseH);
t_set = udate.AddHours(utsetH);
//set should be after rise
if (t_rise > t_set)
{
t_set += TimeSpan.FromDays(1);
}
}
else
{ //not above at all
//Tar{ get { path is always below minimum altitude (e.g. horizon)
t_state = VisibilityState.UpNever;
t_rise = utcdateStart;
t_set = utcdateStart;
}
//The rise time should not precede the beginning of the interval...
if (t_rise < i_rise)
{
t_rise = i_rise;
}
//The set time should not exceed the end of the interval...
if (t_set > i_set)
{
t_set = i_set;
}
return;
}
}
