/*-----------------------------------------------------------------------------
*
* procedure dsinit
*
* this procedure provides deep space contributions to mean motion dot due
* to geopotential resonance with half day and one day orbits.
*
* author : david vallado 719-573-2600 28 jun 2005
*
* inputs :
* cosim, sinim-
* emsq - eccentricity squared
* argpo - argument of perigee
* s1, s2, s3, s4, s5 -
* ss1, ss2, ss3, ss4, ss5 -
* sz1, sz3, sz11, sz13, sz21, sz23, sz31, sz33 -
* t - time
* tc -
* gsto - greenwich sidereal time rad
* mo - mean anomaly
* mdot - mean anomaly dot (rate)
* no - mean motion
* nodeo - right ascension of ascending node
* nodedot - right ascension of ascending node dot (rate)
* xpidot -
* z1, z3, z11, z13, z21, z23, z31, z33 -
* eccm - eccentricity
* argpm - argument of perigee
* inclm - inclination
* mm - mean anomaly
* xn - mean motion
* nodem - right ascension of ascending node
*
* outputs :
* em - eccentricity
* argpm - argument of perigee
* inclm - inclination
* mm - mean anomaly
* nm - mean motion
* nodem - right ascension of ascending node
* irez - flag for resonance 0-none, 1-one day, 2-half day
* atime -
* d2201, d2211, d3210, d3222, d4410, d4422, d5220, d5232, d5421, d5433 -
* dedt -
* didt -
* dmdt -
* dndt -
* dnodt -
* domdt -
* del1, del2, del3 -
* ses , sghl , sghs , sgs , shl , shs , sis , sls
* theta -
* xfact -
* xlamo -
* xli -
* xni
*
* locals :
* ainv2 -
* aonv -
* cosisq -
* eoc -
* f220, f221, f311, f321, f322, f330, f441, f442, f522, f523, f542, f543 -
* g200, g201, g211, g300, g310, g322, g410, g422, g520, g521, g532, g533 -
* sini2 -
* temp -
* temp1 -
* theta -
* xno2 -
*
* coupling :
* getgravconst
*
* references :
* hoots, roehrich, norad spacetrack report #3 1980
* hoots, norad spacetrack report #6 1986
* hoots, schumacher and glover 2004
* vallado, crawford, hujsak, kelso 2006
* ----------------------------------------------------------------------------*/
public DsinitResult dsinit(DsinitOptions dsinitOptions)
{
Globals globals = new Globals();
double pi = globals.pi;
double twoPi = globals.twoPi;
double xke = globals.xke;
double x2o3 = globals.x2o3;
double cosim = dsinitOptions.cosim;
double argpo = dsinitOptions.argpo;
double s1 = dsinitOptions.s1;
double s2 = dsinitOptions.s2;
double s3 = dsinitOptions.s3;
double s4 = dsinitOptions.s4;
double s5 = dsinitOptions.s5;
double sinim = dsinitOptions.sinim;
double ss1 = dsinitOptions.ss1;
double ss2 = dsinitOptions.ss2;
double ss3 = dsinitOptions.ss3;
double ss4 = dsinitOptions.ss4;
double ss5 = dsinitOptions.ss5;
double sz1 = dsinitOptions.sz1;
double sz3 = dsinitOptions.sz3;
double sz11 = dsinitOptions.sz11;
double sz13 = dsinitOptions.sz13;
double sz21 = dsinitOptions.sz21;
double sz23 = dsinitOptions.sz23;
double sz31 = dsinitOptions.sz31;
double sz33 = dsinitOptions.sz33;
double t = dsinitOptions.t;
double tc = dsinitOptions.tc;
double gsto = dsinitOptions.gsto;
double mo = dsinitOptions.mo;
double mdot = dsinitOptions.mdot;
double no = dsinitOptions.no;
double nodeo = dsinitOptions.nodeo;
double nodedot = dsinitOptions.nodedot;
double xpidot = dsinitOptions.xpidot;
double z1 = dsinitOptions.z1;
double z3 = dsinitOptions.z3;
double z11 = dsinitOptions.z11;
double z13 = dsinitOptions.z13;
double z21 = dsinitOptions.z21;
double z23 = dsinitOptions.z23;
double z31 = dsinitOptions.z31;
double z33 = dsinitOptions.z33;
double ecco = dsinitOptions.ecco;
double eccsq = dsinitOptions.eccsq;
double emsq = dsinitOptions.emsq;
double em = dsinitOptions.em;
double argpm = dsinitOptions.argpm;
double inclm = dsinitOptions.inclm;
double mm = dsinitOptions.mm;
double nm = dsinitOptions.nm;
double nodem = dsinitOptions.nodem;
double irez = dsinitOptions.irez;
double atime = dsinitOptions.atime;
double d2201 = dsinitOptions.d2201;
double d2211 = dsinitOptions.d2211;
double d3210 = dsinitOptions.d3210;
double d3222 = dsinitOptions.d3222;
double d4410 = dsinitOptions.d4410;
double d4422 = dsinitOptions.d4422;
double d5220 = dsinitOptions.d5220;
double d5232 = dsinitOptions.d5232;
double d5421 = dsinitOptions.d5421;
double d5433 = dsinitOptions.d5433;
double dedt = dsinitOptions.dedt;
double didt = dsinitOptions.didt;
double dmdt = dsinitOptions.dmdt;
double dnodt = dsinitOptions.dnodt;
double domdt = dsinitOptions.domdt;
double del1 = dsinitOptions.del1;
double del2 = dsinitOptions.del2;
double del3 = dsinitOptions.del3;
double xfact = dsinitOptions.xfact;
double xlamo = dsinitOptions.xlamo;
double xli = dsinitOptions.xli;
double xni = dsinitOptions.xni;
double f220 = 0.0;
double f221 = 0.0;
double f311 = 0.0;
double f321 = 0.0;
double f322 = 0.0;
double f330 = 0.0;
double f441 = 0.0;
double f442 = 0.0;
double f522 = 0.0;
double f523 = 0.0;
double f542 = 0.0;
double f543 = 0.0;
double g200 = 0.0;
double g201 = 0.0;
double g211 = 0.0;
double g300 = 0.0;
double g310 = 0.0;
double g322 = 0.0;
double g410 = 0.0;
double g422 = 0.0;
double g520 = 0.0;
double g521 = 0.0;
double g532 = 0.0;
double g533 = 0.0;
double sini2 = 0.0;
double temp = 0.0;
double temp1 = 0.0;
double xno2 = 0.0;
double ainv2 = 0.0;
double aonv = 0.0;
double cosisq = 0.0;
double eoc = 0.0;
double q22 = 1.7891679e-6;
double q31 = 2.1460748e-6;
double q33 = 2.2123015e-7;
double root22 = 1.7891679e-6;
double root44 = 7.3636953e-9;
double root54 = 2.1765803e-9;
double rptim = 4.37526908801129966e-3; // equates to 7.29211514668855e-5 rad/sec
double root32 = 3.7393792e-7;
double root52 = 1.1428639e-7;
double znl = 1.5835218e-4;
double zns = 1.19459e-5;
// -------------------- deep space initialization ------------
irez = 0;
if ((nm < 0.0052359877) && (nm > 0.0034906585))
{
irez = 1;
}
if ((nm >= 8.26e-3) && (nm <= 9.24e-3) && (em >= 0.5))
{
irez = 2;
}
// ------------------------ do solar terms -------------------
double ses = ss1 * zns * ss5;
double sis = ss2 * zns * (sz11 + sz13);
double sls = -zns * ss3 * ((sz1 + sz3) - 14.0 - (6.0 * emsq));
double sghs = ss4 * zns * ((sz31 + sz33) - 6.0);
double shs = -zns * ss2 * (sz21 + sz23);
// sgp4fix for 180 deg incl
if (inclm < 5.2359877e-2 || inclm > pi - 5.2359877e-2)
{
shs = 0.0;
}
if (sinim != 0.0)
{
shs /= sinim;
}
double sgs = sghs - (cosim * shs);
// ------------------------- do lunar terms ------------------
dedt = ses + (s1 * znl * s5);
didt = sis + (s2 * znl * (z11 + z13));
dmdt = sls - (znl * s3 * ((z1 + z3) - 14.0 - (6.0 * emsq)));
double sghl = s4 * znl * ((z31 + z33) - 6.0);
double shll = -znl * s2 * (z21 + z23);
// sgp4fix for 180 deg incl
if ((inclm < 5.2359877e-2) || (inclm > (pi - 5.2359877e-2)))
{
shll = 0.0;
}
domdt = sgs + sghl;
dnodt = shs;
if (sinim != 0.0)
{
domdt -= (cosim / sinim) * shll;
dnodt += shll / sinim;
}
// ----------- calculate deep space resonance effects --------
double dndt = 0.0;
double theta = (gsto + (tc * rptim)) % twoPi;
em += dedt * t;
inclm += didt * t;
argpm += domdt * t;
nodem += dnodt * t;
mm += dmdt * t;
// sgp4fix for negative inclinations
// the following if statement should be commented out
// if (inclm < 0.0)
// {
// inclm = -inclm;
// argpm = argpm - pi;
// nodem = nodem + pi;
// }
// -------------- initialize the resonance terms -------------
if (irez != 0)
{
aonv = (Math.Pow((nm / xke), x2o3));
// ---------- geopotential resonance for 12 hour orbits ------
if (irez == 2)
{
cosisq = cosim * cosim;
double emo = em;
em = ecco;
double emsqo = emsq;
emsq = eccsq;
eoc = em * emsq;
g201 = -0.306 - ((em - 0.64) * 0.440);
if (em <= 0.65)
{
g211 = (3.616 - (13.2470 * em)) + (16.2900 * emsq);
g310 = ((-19.302 + (117.3900 * em)) - (228.4190 * emsq)) + (156.5910 * eoc);
g322 = ((-18.9068 + (109.7927 * em)) - (214.6334 * emsq)) + (146.5816 * eoc);
g410 = ((-41.122 + (242.6940 * em)) - (471.0940 * emsq)) + (313.9530 * eoc);
g422 = ((-146.407 + (841.8800 * em)) - (1629.014 * emsq)) + (1083.4350 * eoc);
g520 = ((-532.114 + (3017.977 * em)) - (5740.032 * emsq)) + (3708.2760 * eoc);
}
else
{
g211 = ((-72.099 + (331.819 * em)) - (508.738 * emsq)) + (266.724 * eoc);
g310 = ((-346.844 + (1582.851 * em)) - (2415.925 * emsq)) + (1246.113 * eoc);
g322 = ((-342.585 + (1554.908 * em)) - (2366.899 * emsq)) + (1215.972 * eoc);
g410 = ((-1052.797 + (4758.686 * em)) - (7193.992 * emsq)) + (3651.957 * eoc);
g422 = ((-3581.690 + (16178.110 * em)) - (24462.770 * emsq)) + (12422.520 * eoc);
if (em > 0.715)
{
g520 = ((-5149.66 + (29936.92 * em)) - (54087.36 * emsq)) + (31324.56 * eoc);
}
else
{
g520 = (1464.74 - (4664.75 * em)) + (3763.64 * emsq);
}
}
if (em < 0.7)
{
g533 = ((-919.22770 + (4988.6100 * em)) - (9064.7700 * emsq)) + (5542.21 * eoc);
g521 = ((-822.71072 + (4568.6173 * em)) - (8491.4146 * emsq)) + (5337.524 * eoc);
g532 = ((-853.66600 + (4690.2500 * em)) - (8624.7700 * emsq)) + (5341.4 * eoc);
}
else
{
g533 = ((-37995.780 + (161616.52 * em)) - (229838.20 * emsq)) + (109377.94 * eoc);
g521 = ((-51752.104 + (218913.95 * em)) - (309468.16 * emsq)) + (146349.42 * eoc);
g532 = ((-40023.880 + (170470.89 * em)) - (242699.48 * emsq)) + (115605.82 * eoc);
}
sini2 = sinim * sinim;
f220 = 0.75 * (1.0 + (2.0 * cosim) + cosisq);
f221 = 1.5 * sini2;
f321 = 1.875 * sinim * (1.0 - (2.0 * cosim) - (3.0 * cosisq));
f322 = -1.875 * sinim * ((1.0 + (2.0 * cosim)) - (3.0 * cosisq));
f441 = 35.0 * sini2 * f220;
f442 = 39.3750 * sini2 * sini2;
f522 = 9.84375 * sinim * ((sini2 * (1.0 - (2.0 * cosim) - (5.0 * cosisq)))
+ (0.33333333 * (-2.0 + (4.0 * cosim) + (6.0 * cosisq))));
f523 = sinim * ((4.92187512 * sini2 * ((-2.0 - (4.0 * cosim)) + (10.0 * cosisq)))
+ (6.56250012 * ((1.0 + (2.0 * cosim)) - (3.0 * cosisq))));
f542 = 29.53125 * sinim * ((2.0 - (8.0 * cosim))
+ (cosisq * (-12.0 + (8.0 * cosim) + (10.0 * cosisq))));
f543 = 29.53125 * sinim * ((-2.0 - (8.0 * cosim))
+ (cosisq * ((12.0 + (8.0 * cosim)) - (10.0 * cosisq))));
xno2 = nm * nm;
ainv2 = aonv * aonv;
temp1 = 3.0 * xno2 * ainv2;
temp = temp1 * root22;
d2201 = temp * f220 * g201;
d2211 = temp * f221 * g211;
temp1 *= aonv;
temp = temp1 * root32;
d3210 = temp * f321 * g310;
d3222 = temp * f322 * g322;
temp1 *= aonv;
temp = 2.0 * temp1 * root44;
d4410 = temp * f441 * g410;
d4422 = temp * f442 * g422;
temp1 *= aonv;
temp = temp1 * root52;
d5220 = temp * f522 * g520;
d5232 = temp * f523 * g532;
temp = 2.0 * temp1 * root54;
d5421 = temp * f542 * g521;
d5433 = temp * f543 * g533;
xlamo = ((mo + nodeo + nodeo) - (theta + theta)) % twoPi;
xfact = (mdot + dmdt + (2.0 * ((nodedot + dnodt) - rptim))) - no;
em = emo;
emsq = emsqo;
}
// ---------------- synchronous resonance terms --------------
if (irez == 1)
{
g200 = 1.0 + (emsq * (-2.5 + (0.8125 * emsq)));
g310 = 1.0 + (2.0 * emsq);
g300 = 1.0 + (emsq * (-6.0 + (6.60937 * emsq)));
f220 = 0.75 * (1.0 + cosim) * (1.0 + cosim);
f311 = (0.9375 * sinim * sinim * (1.0 + (3.0 * cosim))) - (0.75 * (1.0 + cosim));
f330 = 1.0 + cosim;
f330 *= 1.875 * f330 * f330;
del1 = 3.0 * nm * nm * aonv * aonv;
del2 = 2.0 * del1 * f220 * g200 * q22;
del3 = 3.0 * del1 * f330 * g300 * q33 * aonv;
del1 = del1 * f311 * g310 * q31 * aonv;
xlamo = ((mo + nodeo + argpo) - theta) % twoPi;
xfact = (mdot + xpidot + dmdt + domdt + dnodt) - (no + rptim);
}
// ------------ for sgp4, initialize the integrator ----------
xli = xlamo;
xni = no;
atime = 0.0;
nm = no + dndt;
}
DsinitResult dsinitResult = new DsinitResult();
dsinitResult.em = em;
dsinitResult.argpm = argpm;
dsinitResult.inclm = inclm;
dsinitResult.mm = mm;
dsinitResult.nm = nm;
dsinitResult.nodem = nodem;
dsinitResult.irez = irez;
dsinitResult.atime = atime;
dsinitResult.d2201 = d2201;
dsinitResult.d2211 = d2211;
dsinitResult.d3210 = d3210;
dsinitResult.d3222 = d3222;
dsinitResult.d4410 = d4410;
dsinitResult.d4422 = d4422;
dsinitResult.d5220 = d5220;
dsinitResult.d5232 = d5232;
dsinitResult.d5421 = d5421;
dsinitResult.d5433 = d5433;
dsinitResult.dedt = dedt;
dsinitResult.didt = didt;
dsinitResult.dmdt = dmdt;
dsinitResult.dndt = dndt;
dsinitResult.dnodt = dnodt;
dsinitResult.domdt = domdt;
dsinitResult.del1 = del1;
dsinitResult.del2 = del2;
dsinitResult.del3 = del3;
dsinitResult.xfact = xfact;
dsinitResult.xlamo = xlamo;
dsinitResult.xli = xli;
dsinitResult.xni = xni;
return(dsinitResult);
}
/*-----------------------------------------------------------------------------
*
* procedure sgp4init
*
* this procedure initializes variables for sgp4.
*
* author : david vallado 719-573-2600 28 jun 2005
* author : david vallado 719-573-2600 28 jun 2005
*
* inputs :
* opsmode - mode of operation afspc or improved 'a', 'i'
* satn - satellite number
* bstar - sgp4 type drag coefficient kg/m2er
* ecco - eccentricity
* epoch - epoch time in days from jan 0, 1950. 0 hr
* argpo - argument of perigee (output if ds)
* inclo - inclination
* mo - mean anomaly (output if ds)
* no - mean motion
* nodeo - right ascension of ascending node
*
* outputs :
* rec - common values for subsequent calls
* return code - non-zero on error.
* 1 - mean elements, ecc >= 1.0 or ecc < -0.001 or a < 0.95 er
* 2 - mean motion less than 0.0
* 3 - pert elements, ecc < 0.0 or ecc > 1.0
* 4 - semi-latus rectum < 0.0
* 5 - epoch elements are sub-orbital
* 6 - satellite has decayed
*
* locals :
* cnodm , snodm , cosim , sinim , cosomm , sinomm
* cc1sq , cc2 , cc3
* coef , coef1
* cosio4 -
* day -
* dndt -
* em - eccentricity
* emsq - eccentricity squared
* eeta -
* etasq -
* gam -
* argpm - argument of perigee
* nodem -
* inclm - inclination
* mm - mean anomaly
* nm - mean motion
* perige - perigee
* pinvsq -
* psisq -
* qzms24 -
* rtemsq -
* s1, s2, s3, s4, s5, s6, s7 -
* sfour -
* ss1, ss2, ss3, ss4, ss5, ss6, ss7 -
* sz1, sz2, sz3
* sz11, sz12, sz13, sz21, sz22, sz23, sz31, sz32, sz33 -
* tc -
* temp -
* temp1, temp2, temp3 -
* tsi -
* xpidot -
* xhdot1 -
* z1, z2, z3 -
* z11, z12, z13, z21, z22, z23, z31, z32, z33 -
*
* coupling :
* getgravconst-
* initl -
* dscom -
* dpper -
* dsinit -
* sgp4 -
*
* references :
* hoots, roehrich, norad spacetrack report #3 1980
* hoots, norad spacetrack report #6 1986
* hoots, schumacher and glover 2004
* vallado, crawford, hujsak, kelso 2006
* ----------------------------------------------------------------------------*/
public void sgp4init(Satrec satrec, Sgp4initOptions options)
{
Globals globals = new Globals();
double pi = globals.pi;
double earthRadius = globals.earthRadius;
double j2 = globals.j2;
double j4 = globals.j4;
double j3oj2 = globals.j3oj2;
double x2o3 = globals.x2o3;
char opsmode = options.opsmode;
string satn = options.satn;
double epoch = options.epoch;
double xbstar = options.xbstar;
double xecco = options.xecco;
double xargpo = options.xargpo;
double xinclo = options.xinclo;
double xmo = options.xmo;
double xno = options.xno;
double xnodeo = options.xnodeo;
double cosim;
double sinim;
double cc1sq;
double cc2;
double cc3;
double coef;
double coef1;
double cosio4;
double em;
double emsq;
double eeta;
double etasq;
double argpm;
double nodem;
double inclm;
double mm;
double nm;
double perige;
double pinvsq;
double psisq;
double qzms24;
double s1;
double s2;
double s3;
double s4;
double s5;
double sfour;
double ss1;
double ss2;
double ss3;
double ss4;
double ss5;
double sz1;
double sz3;
double sz11;
double sz13;
double sz21;
double sz23;
double sz31;
double sz33;
double tc;
double temp;
double temp1;
double temp2;
double temp3;
double tsi;
double xpidot;
double xhdot1;
double z1;
double z3;
double z11;
double z13;
double z21;
double z23;
double z31;
double z33;
/* ------------------------ initialization --------------------- */
// sgp4fix divisor for divide by zero check on inclination
// the old check used 1.0 + Math.cos(pi-1.0e-9), but then compared it to
// 1.5 e-12, so the threshold was changed to 1.5e-12 for consistency
double temp4 = 1.5e-12;
// ----------- set all near earth variables to zero ------------
satrec.isimp = 0; satrec.method = 'n'; satrec.aycof = 0.0;
satrec.con41 = 0.0; satrec.cc1 = 0.0; satrec.cc4 = 0.0;
satrec.cc5 = 0.0; satrec.d2 = 0.0; satrec.d3 = 0.0;
satrec.d4 = 0.0; satrec.delmo = 0.0; satrec.eta = 0.0;
satrec.argpdot = 0.0; satrec.omgcof = 0.0; satrec.sinmao = 0.0;
satrec.t = 0.0; satrec.t2cof = 0.0; satrec.t3cof = 0.0;
satrec.t4cof = 0.0; satrec.t5cof = 0.0; satrec.x1mth2 = 0.0;
satrec.x7thm1 = 0.0; satrec.mdot = 0.0; satrec.nodedot = 0.0;
satrec.xlcof = 0.0; satrec.xmcof = 0.0; satrec.nodecf = 0.0;
// ----------- set all deep space variables to zero ------------
satrec.irez = 0; satrec.d2201 = 0.0; satrec.d2211 = 0.0;
satrec.d3210 = 0.0; satrec.d3222 = 0.0; satrec.d4410 = 0.0;
satrec.d4422 = 0.0; satrec.d5220 = 0.0; satrec.d5232 = 0.0;
satrec.d5421 = 0.0; satrec.d5433 = 0.0; satrec.dedt = 0.0;
satrec.del1 = 0.0; satrec.del2 = 0.0; satrec.del3 = 0.0;
satrec.didt = 0.0; satrec.dmdt = 0.0; satrec.dnodt = 0.0;
satrec.domdt = 0.0; satrec.e3 = 0.0; satrec.ee2 = 0.0;
satrec.peo = 0.0; satrec.pgho = 0.0; satrec.pho = 0.0;
satrec.pinco = 0.0; satrec.plo = 0.0; satrec.se2 = 0.0;
satrec.se3 = 0.0; satrec.sgh2 = 0.0; satrec.sgh3 = 0.0;
satrec.sgh4 = 0.0; satrec.sh2 = 0.0; satrec.sh3 = 0.0;
satrec.si2 = 0.0; satrec.si3 = 0.0; satrec.sl2 = 0.0;
satrec.sl3 = 0.0; satrec.sl4 = 0.0; satrec.gsto = 0.0;
satrec.xfact = 0.0; satrec.xgh2 = 0.0; satrec.xgh3 = 0.0;
satrec.xgh4 = 0.0; satrec.xh2 = 0.0; satrec.xh3 = 0.0;
satrec.xi2 = 0.0; satrec.xi3 = 0.0; satrec.xl2 = 0.0;
satrec.xl3 = 0.0; satrec.xl4 = 0.0; satrec.xlamo = 0.0;
satrec.zmol = 0.0; satrec.zmos = 0.0; satrec.atime = 0.0;
satrec.xli = 0.0; satrec.xni = 0.0;
// sgp4fix - note the following variables are also passed directly via satrec.
// it is possible to streamline the sgp4init call by deleting the "x"
// variables, but the user would need to set the satrec.* values first. we
// include the additional assignments in case twoline2rv is not used.
satrec.bstar = xbstar;
satrec.ecco = xecco;
satrec.argpo = xargpo;
satrec.inclo = xinclo;
satrec.mo = xmo;
satrec.no = xno;
satrec.nodeo = xnodeo;
// sgp4fix add opsmode
satrec.operationmode = opsmode;
// ------------------------ earth constants -----------------------
// sgp4fix identify constants and allow alternate values
double ss = (78.0 / earthRadius) + 1.0;
// sgp4fix use multiply for speed instead of pow
double qzms2ttemp = (120.0 - 78.0) / earthRadius;
double qzms2t = qzms2ttemp * qzms2ttemp * qzms2ttemp * qzms2ttemp;
satrec.init = 'y';
satrec.t = 0.0;
InitlOptions initlOptions = new InitlOptions();
initlOptions.satn = satn;
initlOptions.ecco = satrec.ecco;
initlOptions.epoch = epoch;
initlOptions.inlco = satrec.inclo;
initlOptions.no = satrec.no;
initlOptions.method = satrec.method;
initlOptions.opsmode = satrec.operationmode;
Initl initl = new Initl();
InitlResult initlResult = new InitlResult();
initlResult = initl.initl(initlOptions); //TODO: Finish impl
double ao = initlResult.ao;
double con42 = initlResult.con42;
double cosio = initlResult.cosio;
double cosio2 = initlResult.cosio2;
double eccsq = initlResult.eccsq;
double omeosq = initlResult.omeosq;
double posq = initlResult.posq;
double rp = initlResult.rp;
double rteosq = initlResult.rteosq;
double sinio = initlResult.sinio;
satrec.no = initlResult.no;
satrec.con41 = initlResult.con41;
satrec.gsto = initlResult.gsto;
satrec.error = 0;
// sgp4fix remove this check as it is unnecessary
// the mrt check in sgp4 handles decaying satellite cases even if the starting
// condition is below the surface of te earth
// if (rp < 1.0)
// {
// printf("// *** satn%d epoch elts sub-orbital ***\n", satn);
// satrec.error = 5;
// }
if (omeosq >= 0.0 || satrec.no >= 0.0)
{
satrec.isimp = 0;
if (rp < (220.0 / earthRadius + 1.0))
{
satrec.isimp = 1;
}
sfour = ss;
qzms24 = qzms2t;
perige = (rp - 1.0) * earthRadius;
// - for perigees below 156 km, s and qoms2t are altered -
if (perige < 156.0)
{
sfour = perige - 78.0;
if (perige < 98.0)
{
sfour = 20.0;
}
// sgp4fix use multiply for speed instead of pow
double qzms24temp = (120.0 - sfour) / earthRadius;
qzms24 = qzms24temp * qzms24temp * qzms24temp * qzms24temp;
sfour = (sfour / earthRadius) + 1.0;
}
pinvsq = 1.0 / posq;
tsi = 1.0 / (ao - sfour);
satrec.eta = ao * satrec.ecco * tsi;
etasq = satrec.eta * satrec.eta;
eeta = satrec.ecco * satrec.eta;
psisq = Math.Abs(1.0 - etasq);
coef = qzms24 * Math.Pow(tsi, 4.0);
coef1 = coef / (Math.Pow(psisq, 3.5));
cc2 = coef1 * satrec.no * ((ao * (1.0 + (1.5 * etasq) + (eeta * (4.0 + etasq))))
+ (((0.375 * j2 * tsi) / psisq) * satrec.con41
* (8.0 + (3.0 * etasq * (8.0 + etasq)))));
satrec.cc1 = satrec.bstar * cc2;
cc3 = 0.0;
if (satrec.ecco > 1.0e-4)
{
cc3 = (-2.0 * coef * tsi * j3oj2 * satrec.no * sinio) / satrec.ecco;
}
satrec.x1mth2 = 1.0 - cosio2;
satrec.cc4 = 2.0 * satrec.no * coef1 * ao * omeosq * (
((satrec.eta * (2.0 + (0.5 * etasq)))
+ (satrec.ecco * (0.5 + (2.0 * etasq))))
- (((j2 * tsi) / (ao * psisq))
* ((-3.0 * satrec.con41 * ((1.0 - (2.0 * eeta)) + (etasq * (1.5 - (0.5 * eeta)))))
+ (0.75 * satrec.x1mth2
* ((2.0 * etasq) - (eeta * (1.0 + etasq)))
* Math.Cos(2.0 * satrec.argpo))))
);
satrec.cc5 = 2.0 * coef1 * ao * omeosq * (1.0 + (2.75 * (etasq + eeta)) + (eeta * etasq));
cosio4 = cosio2 * cosio2;
temp1 = 1.5 * j2 * pinvsq * satrec.no;
temp2 = 0.5 * temp1 * j2 * pinvsq;
temp3 = -0.46875 * j4 * pinvsq * pinvsq * satrec.no;
satrec.mdot = satrec.no + (0.5 * temp1 * rteosq * satrec.con41)
+ (0.0625 * temp2 * rteosq * ((13.0 - (78.0 * cosio2)) + (137.0 * cosio4)));
satrec.argpdot = (-0.5 * temp1 * con42)
+ (0.0625 * temp2 * ((7.0 - (114.0 * cosio2)) + (395.0 * cosio4)))
+ (temp3 * ((3.0 - (36.0 * cosio2)) + (49.0 * cosio4)));
xhdot1 = -temp1 * cosio;
satrec.nodedot = xhdot1 + (((0.5 * temp2 * (4.0 - (19.0 * cosio2)))
+ (2.0 * temp3 * (3.0 - (7.0 * cosio2)))) * cosio);
xpidot = satrec.argpdot + satrec.nodedot;
satrec.omgcof = satrec.bstar * cc3 * Math.Cos(satrec.argpo);
satrec.xmcof = 0.0;
if (satrec.ecco > 1.0e-4)
{
satrec.xmcof = (-x2o3 * coef * satrec.bstar) / eeta;
}
satrec.nodecf = 3.5 * omeosq * xhdot1 * satrec.cc1;
satrec.t2cof = 1.5 * satrec.cc1;
// sgp4fix for divide by zero with xinco = 180 deg
if (Math.Abs(cosio + 1.0) > 1.5e-12)
{
satrec.xlcof = (-0.25 * j3oj2 * sinio * (3.0 + (5.0 * cosio))) / (1.0 + cosio);
}
else
{
satrec.xlcof = (-0.25 * j3oj2 * sinio * (3.0 + (5.0 * cosio))) / temp4;
}
satrec.aycof = -0.5 * j3oj2 * sinio;
// sgp4fix use multiply for speed instead of pow
double delmotemp = 1.0 + (satrec.eta * Math.Cos(satrec.mo));
satrec.delmo = delmotemp * delmotemp * delmotemp;
satrec.sinmao = Math.Sin(satrec.mo);
satrec.x7thm1 = (7.0 * cosio2) - 1.0;
// --------------- deep space initialization -------------
if ((2 * pi) / satrec.no >= 225.0)
{
satrec.method = 'd';
satrec.isimp = 1;
tc = 0.0;
inclm = satrec.inclo;
DscomOptions dscomOptions = new DscomOptions();
dscomOptions.epoch = epoch;
dscomOptions.ep = satrec.ecco;
dscomOptions.argpp = satrec.argpo;
dscomOptions.tc = tc;
dscomOptions.inclp = satrec.inclo;
dscomOptions.nodep = satrec.nodeo;
dscomOptions.np = satrec.no;
dscomOptions.e3 = satrec.e3;
dscomOptions.ee2 = satrec.ee2;
dscomOptions.peo = satrec.peo;
dscomOptions.pgho = satrec.pgho;
dscomOptions.pho = satrec.pho;
dscomOptions.pinco = satrec.pinco;
dscomOptions.plo = satrec.plo;
dscomOptions.se2 = satrec.se2;
dscomOptions.se3 = satrec.se3;
dscomOptions.sgh2 = satrec.sgh2;
dscomOptions.sgh3 = satrec.sgh3;
dscomOptions.sgh4 = satrec.sgh4;
dscomOptions.sh2 = satrec.sh2;
dscomOptions.sh3 = satrec.sh3;
dscomOptions.si2 = satrec.si2;
dscomOptions.si3 = satrec.si3;
dscomOptions.sl2 = satrec.sl2;
dscomOptions.sl3 = satrec.sl3;
dscomOptions.sl4 = satrec.sl4;
dscomOptions.xgh2 = satrec.xgh2;
dscomOptions.xgh3 = satrec.xgh3;
dscomOptions.xgh4 = satrec.xgh4;
dscomOptions.xh2 = satrec.xh2;
dscomOptions.xh3 = satrec.xh3;
dscomOptions.xi2 = satrec.xi2;
dscomOptions.xi3 = satrec.xi3;
dscomOptions.xl2 = satrec.xl2;
dscomOptions.xl3 = satrec.xl3;
dscomOptions.xl4 = satrec.xl4;
dscomOptions.zmol = satrec.zmol;
dscomOptions.zmos = satrec.zmos;
Dscom dscom = new Dscom();
DscomResult dscomResult = new DscomResult();
dscomResult = dscom.dscom(dscomOptions);
satrec.e3 = dscomResult.e3;
satrec.ee2 = dscomResult.ee2;
satrec.peo = dscomResult.peo;
satrec.pgho = dscomResult.pgho;
satrec.pho = dscomResult.pho;
satrec.pinco = dscomResult.pinco;
satrec.plo = dscomResult.plo;
satrec.se2 = dscomResult.se2;
satrec.se3 = dscomResult.se3;
satrec.sgh2 = dscomResult.sgh2;
satrec.sgh3 = dscomResult.sgh3;
satrec.sgh4 = dscomResult.sgh4;
satrec.sh2 = dscomResult.sh2;
satrec.sh3 = dscomResult.sh3;
satrec.si2 = dscomResult.si2;
satrec.si3 = dscomResult.si3;
satrec.sl2 = dscomResult.sl2;
satrec.sl3 = dscomResult.sl3;
satrec.sl4 = dscomResult.sl4;
sinim = dscomResult.sinim;
cosim = dscomResult.cosim;
em = dscomResult.em;
emsq = dscomResult.emsq;
s1 = dscomResult.s1;
s2 = dscomResult.s2;
s3 = dscomResult.s3;
s4 = dscomResult.s4;
s5 = dscomResult.s5;
ss1 = dscomResult.ss1;
ss2 = dscomResult.ss2;
ss3 = dscomResult.ss3;
ss4 = dscomResult.ss4;
ss5 = dscomResult.ss5;
sz1 = dscomResult.sz1;
sz3 = dscomResult.sz3;
sz11 = dscomResult.sz11;
sz13 = dscomResult.sz13;
sz21 = dscomResult.sz21;
sz23 = dscomResult.sz23;
sz31 = dscomResult.sz31;
sz33 = dscomResult.sz33;
satrec.xgh2 = dscomResult.xgh2;
satrec.xgh3 = dscomResult.xgh3;
satrec.xgh4 = dscomResult.xgh4;
satrec.xh2 = dscomResult.xh2;
satrec.xh3 = dscomResult.xh3;
satrec.xi2 = dscomResult.xi2;
satrec.xi3 = dscomResult.xi3;
satrec.xl2 = dscomResult.xl2;
satrec.xl3 = dscomResult.xl3;
satrec.xl4 = dscomResult.xl4;
satrec.zmol = dscomResult.zmol;
satrec.zmos = dscomResult.zmos;
nm = dscomResult.nm;
z1 = dscomResult.z1;
z3 = dscomResult.z3;
z11 = dscomResult.z11;
z13 = dscomResult.z13;
z21 = dscomResult.z21;
z23 = dscomResult.z23;
z31 = dscomResult.z31;
z33 = dscomResult.z33;
DpperOptions dpperOptions = new DpperOptions();
dpperOptions.inclo = inclm;
dpperOptions.init = satrec.init;
dpperOptions.ep = satrec.ecco;
dpperOptions.inclp = satrec.inclo;
dpperOptions.nodep = satrec.nodeo;
dpperOptions.argpp = satrec.argpo;
dpperOptions.mp = satrec.mo;
dpperOptions.opsmode = satrec.operationmode;
Dpper dpper = new Dpper();
DpperResult dpperResult = new DpperResult();
dpperResult = dpper.dpper(satrec, dpperOptions);
satrec.ecco = dpperResult.ep;
satrec.inclo = dpperResult.inclp;
satrec.nodeo = dpperResult.nodep;
satrec.argpo = dpperResult.argpp;
satrec.mo = dpperResult.mp;
argpm = 0.0;
nodem = 0.0;
mm = 0.0;
DsinitOptions dsinitOptions = new DsinitOptions();
dsinitOptions.cosim = cosim;
dsinitOptions.emsq = emsq;
dsinitOptions.argpo = satrec.argpo;
dsinitOptions.s1 = s1;
dsinitOptions.s2 = s2;
dsinitOptions.s3 = s3;
dsinitOptions.s4 = s4;
dsinitOptions.s5 = s5;
dsinitOptions.sinim = sinim;
dsinitOptions.ss1 = ss1;
dsinitOptions.ss2 = ss2;
dsinitOptions.ss3 = ss3;
dsinitOptions.ss4 = ss4;
dsinitOptions.ss5 = ss5;
dsinitOptions.sz1 = sz1;
dsinitOptions.sz3 = sz3;
dsinitOptions.sz11 = sz11;
dsinitOptions.sz13 = sz13;
dsinitOptions.sz21 = sz21;
dsinitOptions.sz23 = sz23;
dsinitOptions.sz31 = sz31;
dsinitOptions.sz33 = sz33;
dsinitOptions.t = satrec.t;
dsinitOptions.tc = tc;
dsinitOptions.gsto = satrec.gsto;
dsinitOptions.mo = satrec.mo;
dsinitOptions.mdot = satrec.mdot;
dsinitOptions.no = satrec.no;
dsinitOptions.nodeo = satrec.nodeo;
dsinitOptions.nodedot = satrec.nodedot;
dsinitOptions.xpidot = xpidot;
dsinitOptions.z1 = z1;
dsinitOptions.z3 = z3;
dsinitOptions.z11 = z11;
dsinitOptions.z13 = z13;
dsinitOptions.z21 = z21;
dsinitOptions.z23 = z23;
dsinitOptions.z31 = z31;
dsinitOptions.z33 = z33;
dsinitOptions.ecco = satrec.ecco;
dsinitOptions.eccsq = eccsq;
dsinitOptions.em = em;
dsinitOptions.argpm = argpm;
dsinitOptions.inclm = inclm;
dsinitOptions.mm = mm;
dsinitOptions.nm = nm;
dsinitOptions.nodem = nodem;
dsinitOptions.irez = satrec.irez;
dsinitOptions.atime = satrec.atime;
dsinitOptions.d2201 = satrec.d2201;
dsinitOptions.d2211 = satrec.d2211;
dsinitOptions.d3210 = satrec.d3210;
dsinitOptions.d3222 = satrec.d3222;
dsinitOptions.d4410 = satrec.d4410;
dsinitOptions.d4422 = satrec.d4422;
dsinitOptions.d5220 = satrec.d5220;
dsinitOptions.d5232 = satrec.d5232;
dsinitOptions.d5421 = satrec.d5421;
dsinitOptions.d5433 = satrec.d5433;
dsinitOptions.dedt = satrec.dedt;
dsinitOptions.didt = satrec.didt;
dsinitOptions.dmdt = satrec.dmdt;
dsinitOptions.dnodt = satrec.dnodt;
dsinitOptions.domdt = satrec.domdt;
dsinitOptions.del1 = satrec.del1;
dsinitOptions.del2 = satrec.del2;
dsinitOptions.del3 = satrec.del3;
dsinitOptions.xfact = satrec.xfact;
dsinitOptions.xlamo = satrec.xlamo;
dsinitOptions.xli = satrec.xli;
dsinitOptions.xni = satrec.xni;
Dsinit dsinit = new Dsinit();
DsinitResult dsinitResult = new DsinitResult();
dsinitResult = dsinit.dsinit(dsinitOptions);
satrec.irez = dsinitResult.irez;
satrec.atime = dsinitResult.atime;
satrec.d2201 = dsinitResult.d2201;
satrec.d2211 = dsinitResult.d2211;
satrec.d3210 = dsinitResult.d3210;
satrec.d3222 = dsinitResult.d3222;
satrec.d4410 = dsinitResult.d4410;
satrec.d4422 = dsinitResult.d4422;
satrec.d5220 = dsinitResult.d5220;
satrec.d5232 = dsinitResult.d5232;
satrec.d5421 = dsinitResult.d5421;
satrec.d5433 = dsinitResult.d5433;
satrec.dedt = dsinitResult.dedt;
satrec.didt = dsinitResult.didt;
satrec.dmdt = dsinitResult.dmdt;
satrec.dnodt = dsinitResult.dnodt;
satrec.domdt = dsinitResult.domdt;
satrec.del1 = dsinitResult.del1;
satrec.del2 = dsinitResult.del2;
satrec.del3 = dsinitResult.del3;
satrec.xfact = dsinitResult.xfact;
satrec.xlamo = dsinitResult.xlamo;
satrec.xli = dsinitResult.xli;
satrec.xni = dsinitResult.xni;
}
// ----------- set variables if not deep space -----------
if (satrec.isimp != 1)
{
cc1sq = satrec.cc1 * satrec.cc1;
satrec.d2 = 4.0 * ao * tsi * cc1sq;
temp = (satrec.d2 * tsi * satrec.cc1) / 3.0;
satrec.d3 = ((17.0 * ao) + sfour) * temp;
satrec.d4 = 0.5 * temp * ao * tsi * ((221.0 * ao) + (31.0 * sfour)) * satrec.cc1;
satrec.t3cof = satrec.d2 + (2.0 * cc1sq);
satrec.t4cof = 0.25 * ((3.0 * satrec.d3)
+ (satrec.cc1 * ((12.0 * satrec.d2) + (10.0 * cc1sq))));
satrec.t5cof = 0.2 * (
(3.0 * satrec.d4)
+ (12.0 * satrec.cc1 * satrec.d3)
+ (6.0 * satrec.d2 * satrec.d2)
+ (15.0 * cc1sq * ((2.0 * satrec.d2) + cc1sq))
);
}
/* finally propogate to zero epoch to initialize all others. */
// sgp4fix take out check to let satellites process until they are actually below earth surface
// if(satrec.error == 0)
}
Sgp4 sgp4 = new Sgp4();
sgp4.sgp4(satrec, 0);
satrec.init = 'n';
/* eslint-enable no-param-reassign */
}
