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DeepSecular() compiles

feature/19
Daniel Warner 2011-03-30 13:50:41 +01:00
parent c4dd1f28be
commit eebc89f6a3
2 changed files with 62 additions and 28 deletions
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89
SGDP4.cpp
View File

@ -1017,7 +1017,8 @@ void SGDP4::DeepSecular(const double& t, double& xll, double& omgasm,
static const double THDT = 4.3752691E-3;
static const double step = 720.0;
static const double STEP2 = 259200.0;
static const double STEP = 720.0;
double xldot = 0.0;
double xndot = 0.0;
@ -1032,11 +1033,17 @@ void SGDP4::DeepSecular(const double& t, double& xll, double& omgasm,
if (!d_resonance_flag_)
return;
if (fabs(d_atime_) < step ||
(d_atime_ < 0.0 && t < d_atime_ - 1.0) ||
(d_atime_ > 0.0 && t > d_atime_ + 1.0)) {
/*
* 1st condition (restart if tsince is less than one time step)
* 2nd condition ()
* 3rd condition ()
*/
if (d_atime_ == 0 ||
fabs(d_atime_) < STEP ||
(d_atime_ > 0.0 && t < d_atime_ - 1.0) ||
(d_atime_ < 0.0 && t > d_atime_ + 1.0)) {
/*
* epoch restart
* restart from epoch
*/
d_atime_ = 0.0;
d_xni_ = RecoveredMeanMotion();
@ -1044,36 +1051,39 @@ void SGDP4::DeepSecular(const double& t, double& xll, double& omgasm,
}
double ft = t - d_atime_;
double delt = 0.0;
if (fabs(ft) >= step) {
/*
* if time difference (ft) is greater than the time step (720.0)
* loop around until d_atime_ is within one time step of t
*/
if (fabs(ft) >= STEP) {
if (t > 0.0)
delt = step;
else
delt = -step;
/*
* calculate step direction to allow d_atime_
* to catch up with t
*/
double delt = -STEP;
if (ft >= 0.0)
delt = STEP;
do {
/*
* integrator
*/
d_xli_ = d_xli_ + xldot * delt + xndot * step2;
d_xni_ = d_xni_ + xndot * delt + xnddt * step2;
DeepSpaceCalcIntegrator(delt, STEP2, xndot, xnddt, xldot);
DeepSpaceCalcDotTerms(xndot, xnddt, xldot);
d_atime_ += delt;
ft = t - d_atime_;
} while (fabs(ft) >= step);
} while (fabs(ft) >= STEP);
}
/*
* calculate dot terms
*/
DeepSpaceCalcDotTerms(xndot, xnddt, xldot);
/*
* integrator
*/
xn = d_xni_ + xndot * ft + xnddt * ft * ft * 0.5;
double xl = d_xli_ + xldot * ft + xndot * ft * ft * 0.5;
double temp = -xnodes + i_gsto_ + t * THDT;
const double xl = d_xli_ + xldot * ft + xndot * ft * ft * 0.5;
const double temp = -xnodes + i_gsto_ + t * THDT;
if (!d_synchronous_flag_)
xll = xl + temp + temp;
@ -1094,11 +1104,12 @@ void SGDP4::DeepSpaceCalcDotTerms(double& xndot, double& xnddt, double& xldot) {
if (d_synchronous_flag_) {
xndot = d_del1_ * sin(d_xli_ - d_fasx2_) + d_del2_ * sin(2.0 * (d_xli_ - d_fasx4_))
1 + d_del3_ * sin(3.0 * (d_xli_ - d_fasx6_));
xnddt = d_del1_ * cos(d_xli_ - d_fasx2_)
+ 2.0 * d_del2_ * cos(2.0 * (d_xli_ - d_fasx4_))
+ 3.0 * d_del3_ * cos(3.0 * (d_xli_ - d_fasx6_));
xndot = d_del1_ * sin(d_xli_ - d_fasx2_) +
d_del2_ * sin(2.0 * (d_xli_ - d_fasx4_)) +
d_del3_ * sin(3.0 * (d_xli_ - d_fasx6_));
xnddt = d_del1_ * cos(d_xli_ - d_fasx2_) + 2.0 *
d_del2_ * cos(2.0 * (d_xli_ - d_fasx4_)) + 3.0 *
d_del3_ * cos(3.0 * (d_xli_ - d_fasx6_));
} else {
@ -1131,3 +1142,25 @@ void SGDP4::DeepSpaceCalcDotTerms(double& xndot, double& xnddt, double& xldot) {
xldot = d_xni_ + d_xfact_;
xnddt = xnddt * xldot;
}
/*
* deep space integrator for time period of delt
*/
void SGDP4::DeepSpaceCalcIntegrator(const double& delt, const double& step2, double& xndot, double& xnddt, double& xldot) {
/*
* calculate dot terms
*/
DeepSpaceCalcDotTerms(xndot, xnddt, xldot);
/*
* integrator
*/
d_xli_ = d_xli_ + xldot * delt + xndot * step2;
d_xni_ = d_xni_ + xndot * delt + xnddt * step2;
/*
* increment integrator time
*/
d_atime_ += delt;
}

1
SGDP4.h
View File

@ -35,6 +35,7 @@ private:
const double& x3thm1, const double& x1mth2, const double& x7thm1,
const double& cosio, const double& sinio);
void DeepSpaceCalcDotTerms(double& xndot, double& xnddt, double& xldot);
void DeepSpaceCalcIntegrator(const double& delt, const double& step2, double& xndot, double& xnddt, double& xldot);
bool first_run_;