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GravityCircle.cpp
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/**
* \file GravityCircle.cpp
* \brief Implementation for GeographicLib::GravityCircle class
*
* Copyright (c) Charles Karney (2011-2020) <karney@alum.mit.edu> and licensed
* under the MIT/X11 License. For more information, see
* https://geographiclib.sourceforge.io/
**********************************************************************/
#include <GeographicLib/GravityCircle.hpp>
#include <fstream>
#include <sstream>
#include <GeographicLib/Geocentric.hpp>
namespace GeographicLib {
using namespace std;
GravityCircle::GravityCircle(mask caps, real a, real f, real lat, real h,
real Z, real P, real cphi, real sphi,
real amodel, real GMmodel,
real dzonal0, real corrmult,
real gamma0, real gamma, real frot,
const CircularEngine& gravitational,
const CircularEngine& disturbing,
const CircularEngine& correction)
: _caps(caps)
, _a(a)
, _f(f)
, _lat(Math::LatFix(lat))
, _h(h)
, _zZ(Z)
, _pPx(P)
, _invR(1 / hypot(_pPx, _zZ))
, _cpsi(_pPx * _invR)
, _spsi(_zZ * _invR)
, _cphi(cphi)
, _sphi(sphi)
, _amodel(amodel)
, _gGMmodel(GMmodel)
, _dzonal0(dzonal0)
, _corrmult(corrmult)
, _gamma0(gamma0)
, _gamma(gamma)
, _frot(frot)
, _gravitational(gravitational)
, _disturbing(disturbing)
, _correction(correction)
{}
Math::real GravityCircle::Gravity(real lon,
real& gx, real& gy, real& gz) const {
real slam, clam, M[Geocentric::dim2_];
Math::sincosd(lon, slam, clam);
real Wres = W(slam, clam, gx, gy, gz);
Geocentric::Rotation(_sphi, _cphi, slam, clam, M);
Geocentric::Unrotate(M, gx, gy, gz, gx, gy, gz);
return Wres;
}
Math::real GravityCircle::Disturbance(real lon, real& deltax, real& deltay,
real& deltaz) const {
real slam, clam, M[Geocentric::dim2_];
Math::sincosd(lon, slam, clam);
real Tres = InternalT(slam, clam, deltax, deltay, deltaz, true, true);
Geocentric::Rotation(_sphi, _cphi, slam, clam, M);
Geocentric::Unrotate(M, deltax, deltay, deltaz, deltax, deltay, deltaz);
return Tres;
}
Math::real GravityCircle::GeoidHeight(real lon) const {
if ((_caps & GEOID_HEIGHT) != GEOID_HEIGHT)
return Math::NaN();
real slam, clam, dummy;
Math::sincosd(lon, slam, clam);
real T = InternalT(slam, clam, dummy, dummy, dummy, false, false);
real correction = _corrmult * _correction(slam, clam);
return T/_gamma0 + correction;
}
void GravityCircle::SphericalAnomaly(real lon,
real& Dg01, real& xi, real& eta) const {
if ((_caps & SPHERICAL_ANOMALY) != SPHERICAL_ANOMALY) {
Dg01 = xi = eta = Math::NaN();
return;
}
real slam, clam;
Math::sincosd(lon, slam, clam);
real
deltax, deltay, deltaz,
T = InternalT(slam, clam, deltax, deltay, deltaz, true, false);
// Rotate cartesian into spherical coordinates
real MC[Geocentric::dim2_];
Geocentric::Rotation(_spsi, _cpsi, slam, clam, MC);
Geocentric::Unrotate(MC, deltax, deltay, deltaz, deltax, deltay, deltaz);
// H+M, Eq 2-151c
Dg01 = - deltaz - 2 * T * _invR;
xi = -(deltay/_gamma) / Math::degree();
eta = -(deltax/_gamma) / Math::degree();
}
Math::real GravityCircle::W(real slam, real clam,
real& gX, real& gY, real& gZ) const {
real Wres = V(slam, clam, gX, gY, gZ) + _frot * _pPx / 2;
gX += _frot * clam;
gY += _frot * slam;
return Wres;
}
Math::real GravityCircle::V(real slam, real clam,
real& GX, real& GY, real& GZ) const {
if ((_caps & GRAVITY) != GRAVITY) {
GX = GY = GZ = Math::NaN();
return Math::NaN();
}
real
Vres = _gravitational(slam, clam, GX, GY, GZ),
f = _gGMmodel / _amodel;
Vres *= f;
GX *= f;
GY *= f;
GZ *= f;
return Vres;
}
Math::real GravityCircle::InternalT(real slam, real clam,
real& deltaX, real& deltaY, real& deltaZ,
bool gradp, bool correct) const {
if (gradp) {
if ((_caps & DISTURBANCE) != DISTURBANCE) {
deltaX = deltaY = deltaZ = Math::NaN();
return Math::NaN();
}
} else {
if ((_caps & DISTURBING_POTENTIAL) != DISTURBING_POTENTIAL)
return Math::NaN();
}
if (_dzonal0 == 0)
correct = false;
real T = (gradp
? _disturbing(slam, clam, deltaX, deltaY, deltaZ)
: _disturbing(slam, clam));
T = (T / _amodel - (correct ? _dzonal0 : 0) * _invR) * _gGMmodel;
if (gradp) {
real f = _gGMmodel / _amodel;
deltaX *= f;
deltaY *= f;
deltaZ *= f;
if (correct) {
real r3 = _gGMmodel * _dzonal0 * _invR * _invR * _invR;
deltaX += _pPx * clam * r3;
deltaY += _pPx * slam * r3;
deltaZ += _zZ * r3;
}
}
return T;
}
} // namespace GeographicLib
Geocentric.hpp
Header for GeographicLib::Geocentric class.
real
GeographicLib::Math::real real
Definition GeodSolve.cpp:28
GravityCircle.hpp
Header for GeographicLib::GravityCircle class.
GeographicLib::GravityCircle::GravityCircle
GravityCircle()
Definition GravityCircle.hpp:83
GeographicLib::Math::real
double real
Definition Math.hpp:110
GeographicLib
Namespace for GeographicLib.
Definition Accumulator.cpp:12
std
Definition NearestNeighbor.hpp:806