Gravity.cpp
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/**
* \file Gravity.cpp
* \brief Command line utility for evaluating gravity fields
*
* Copyright (c) Charles Karney (2011-2022) <karney@alum.mit.edu> and licensed
* under the MIT/X11 License. For more information, see
* https://geographiclib.sourceforge.io/
*
* See the <a href="Gravity.1.html">man page</a> for usage information.
**********************************************************************/
#include <iostream>
#include <string>
#include <sstream>
#include <fstream>
#include <GeographicLib/GravityModel.hpp>
#include <GeographicLib/GravityCircle.hpp>
#include <GeographicLib/DMS.hpp>
#include <GeographicLib/Utility.hpp>
#if defined(_MSC_VER)
// Squelch warnings about constant conditional and enum-float expressions
// and potentially uninitialized local variables
# pragma warning (disable: 4127 5055 4701)
#endif
#include "Gravity.usage"
int main(int argc, const char* const argv[]) {
try {
using namespace GeographicLib;
typedef Math::real real;
Utility::set_digits();
bool verbose = false, longfirst = false;
std::string dir;
std::string model = GravityModel::DefaultGravityName();
std::string istring, ifile, ofile, cdelim;
char lsep = ';';
real lat = 0, h = 0;
bool circle = false;
int prec = -1, Nmax = -1, Mmax = -1;
enum {
GRAVITY = 0,
DISTURBANCE = 1,
ANOMALY = 2,
UNDULATION = 3,
};
unsigned mode = GRAVITY;
for (int m = 1; m < argc; ++m) {
std::string arg(argv[m]);
if (arg == "-n") {
if (++m == argc) return usage(1, true);
model = argv[m];
} else if (arg == "-d") {
if (++m == argc) return usage(1, true);
dir = argv[m];
} else if (arg == "-N") {
if (++m == argc) return usage(1, true);
try {
Nmax = Utility::val<int>(std::string(argv[m]));
if (Nmax < 0) {
std::cerr << "Maximum degree " << argv[m] << " is negative\n";
return 1;
}
}
catch (const std::exception&) {
std::cerr << "Precision " << argv[m] << " is not a number\n";
return 1;
}
} else if (arg == "-M") {
if (++m == argc) return usage(1, true);
try {
Mmax = Utility::val<int>(std::string(argv[m]));
if (Mmax < 0) {
std::cerr << "Maximum order " << argv[m] << " is negative\n";
return 1;
}
}
catch (const std::exception&) {
std::cerr << "Precision " << argv[m] << " is not a number\n";
return 1;
}
} else if (arg == "-G")
mode = GRAVITY;
else if (arg == "-D")
mode = DISTURBANCE;
else if (arg == "-A")
mode = ANOMALY;
else if (arg == "-H")
mode = UNDULATION;
else if (arg == "-c") {
if (m + 2 >= argc) return usage(1, true);
try {
using std::fabs;
DMS::flag ind;
lat = DMS::Decode(std::string(argv[++m]), ind);
if (ind == DMS::LONGITUDE)
throw GeographicErr("Bad hemisphere letter on latitude");
if (!(fabs(lat) <= Math::qd))
throw GeographicErr("Latitude not in [-" + std::to_string(Math::qd)
+ "d, " + std::to_string(Math::qd) + "d]");
h = Utility::val<real>(std::string(argv[++m]));
circle = true;
}
catch (const std::exception& e) {
std::cerr << "Error decoding argument of " << arg << ": "
<< e.what() << "\n";
return 1;
}
} else if (arg == "-w")
longfirst = !longfirst;
else if (arg == "-p") {
if (++m == argc) return usage(1, true);
try {
prec = Utility::val<int>(std::string(argv[m]));
}
catch (const std::exception&) {
std::cerr << "Precision " << argv[m] << " is not a number\n";
return 1;
}
} else if (arg == "-v")
verbose = true;
else if (arg == "--input-string") {
if (++m == argc) return usage(1, true);
istring = argv[m];
} else if (arg == "--input-file") {
if (++m == argc) return usage(1, true);
ifile = argv[m];
} else if (arg == "--output-file") {
if (++m == argc) return usage(1, true);
ofile = argv[m];
} else if (arg == "--line-separator") {
if (++m == argc) return usage(1, true);
if (std::string(argv[m]).size() != 1) {
std::cerr << "Line separator must be a single character\n";
return 1;
}
lsep = argv[m][0];
} else if (arg == "--comment-delimiter") {
if (++m == argc) return usage(1, true);
cdelim = argv[m];
} else if (arg == "--version") {
std::cout << argv[0] << ": GeographicLib version "
<< GEOGRAPHICLIB_VERSION_STRING << "\n";
return 0;
} else {
int retval = usage(!(arg == "-h" || arg == "--help"), arg != "--help");
if (arg == "-h")
std::cout<< "\nDefault gravity path = \""
<< GravityModel::DefaultGravityPath()
<< "\"\nDefault gravity name = \""
<< GravityModel::DefaultGravityName()
<< "\"\n";
return retval;
}
}
if (!ifile.empty() && !istring.empty()) {
std::cerr << "Cannot specify --input-string and --input-file together\n";
return 1;
}
if (ifile == "-") ifile.clear();
std::ifstream infile;
std::istringstream instring;
if (!ifile.empty()) {
infile.open(ifile.c_str());
if (!infile.is_open()) {
std::cerr << "Cannot open " << ifile << " for reading\n";
return 1;
}
} else if (!istring.empty()) {
std::string::size_type m = 0;
while (true) {
m = istring.find(lsep, m);
if (m == std::string::npos)
break;
istring[m] = '\n';
}
instring.str(istring);
}
std::istream* input = !ifile.empty() ? &infile :
(!istring.empty() ? &instring : &std::cin);
std::ofstream outfile;
if (ofile == "-") ofile.clear();
if (!ofile.empty()) {
outfile.open(ofile.c_str());
if (!outfile.is_open()) {
std::cerr << "Cannot open " << ofile << " for writing\n";
return 1;
}
}
std::ostream* output = !ofile.empty() ? &outfile : &std::cout;
switch (mode) {
case GRAVITY:
prec = std::min(16 + Math::extra_digits(), prec < 0 ? 5 : prec);
break;
case DISTURBANCE:
case ANOMALY:
prec = std::min(14 + Math::extra_digits(), prec < 0 ? 3 : prec);
break;
case UNDULATION:
default:
prec = std::min(12 + Math::extra_digits(), prec < 0 ? 4 : prec);
break;
}
int retval = 0;
try {
using std::isfinite;
const GravityModel g(model, dir, Nmax, Mmax);
if (circle) {
if (!isfinite(h))
throw GeographicErr("Bad height");
else if (mode == UNDULATION && h != 0)
throw GeographicErr("Height should be zero for geoid undulations");
}
if (verbose) {
std::cerr << "Gravity file: " << g.GravityFile() << "\n"
<< "Name: " << g.GravityModelName() << "\n"
<< "Description: " << g.Description() << "\n"
<< "Date & Time: " << g.DateTime() << "\n";
}
unsigned mask = (mode == GRAVITY ? GravityModel::GRAVITY :
(mode == DISTURBANCE ? GravityModel::DISTURBANCE :
(mode == ANOMALY ? GravityModel::SPHERICAL_ANOMALY :
GravityModel::GEOID_HEIGHT))); // mode == UNDULATION
const GravityCircle c(circle ? g.Circle(lat, h, mask) : GravityCircle());
std::string s, eol, stra, strb;
std::istringstream str;
while (std::getline(*input, s)) {
try {
eol = "\n";
if (!cdelim.empty()) {
std::string::size_type m = s.find(cdelim);
if (m != std::string::npos) {
eol = " " + s.substr(m) + "\n";
s = s.substr(0, m);
}
}
str.clear(); str.str(s);
real lon;
if (circle) {
if (!(str >> strb))
throw GeographicErr("Incomplete input: " + s);
DMS::flag ind;
lon = DMS::Decode(strb, ind);
if (ind == DMS::LATITUDE)
throw GeographicErr("Bad hemisphere letter on " + strb);
} else {
if (!(str >> stra >> strb))
throw GeographicErr("Incomplete input: " + s);
DMS::DecodeLatLon(stra, strb, lat, lon, longfirst);
h = 0;
if (!(str >> h)) // h is optional
str.clear();
if (mode == UNDULATION && h != 0)
throw GeographicErr("Height must be zero for geoid heights");
}
if (str >> stra)
throw GeographicErr("Extra junk in input: " + s);
switch (mode) {
case GRAVITY:
{
real gx, gy, gz;
if (circle) {
c.Gravity(lon, gx, gy, gz);
} else {
g.Gravity(lat, lon, h, gx, gy, gz);
}
*output << Utility::str(gx, prec) << " "
<< Utility::str(gy, prec) << " "
<< Utility::str(gz, prec) << eol;
}
break;
case DISTURBANCE:
{
real deltax, deltay, deltaz;
if (circle) {
c.Disturbance(lon, deltax, deltay, deltaz);
} else {
g.Disturbance(lat, lon, h, deltax, deltay, deltaz);
}
// Convert to mGals
*output << Utility::str(deltax * 100000, prec) << " "
<< Utility::str(deltay * 100000, prec) << " "
<< Utility::str(deltaz * 100000, prec)
<< eol;
}
break;
case ANOMALY:
{
real Dg01, xi, eta;
if (circle)
c.SphericalAnomaly(lon, Dg01, xi, eta);
else
g.SphericalAnomaly(lat, lon, h, Dg01, xi, eta);
Dg01 *= 100000; // Convert to mGals
xi *= Math::ds; // Convert to arcsecs
eta *= Math::ds;
*output << Utility::str(Dg01, prec) << " "
<< Utility::str(xi, prec) << " "
<< Utility::str(eta, prec) << eol;
}
break;
case UNDULATION:
default:
{
real N = circle ? c.GeoidHeight(lon) : g.GeoidHeight(lat, lon);
*output << Utility::str(N, prec) << eol;
}
break;
}
}
catch (const std::exception& e) {
*output << "ERROR: " << e.what() << "\n";
retval = 1;
}
}
}
catch (const std::exception& e) {
std::cerr << "Error reading " << model << ": " << e.what() << "\n";
retval = 1;
}
return retval;
}
catch (const std::exception& e) {
std::cerr << "Caught exception: " << e.what() << "\n";
return 1;
}
catch (...) {
std::cerr << "Caught unknown exception\n";
return 1;
}
}
DMS.hpp
Header for GeographicLib::DMS class.
real
GeographicLib::Math::real real
Definition: GeodSolve.cpp:29
GravityCircle.hpp
Header for GeographicLib::GravityCircle class.
GravityModel.hpp
Header for GeographicLib::GravityModel class.
main
int main(int argc, const char *const argv[])
Definition: Gravity.cpp:29
Utility.hpp
Header for GeographicLib::Utility class.
GeographicLib::DMS::flag
flag
Definition: DMS.hpp:41
GeographicLib::GeographicErr
Exception handling for GeographicLib.
Definition: Constants.hpp:316
GeographicLib::GravityCircle
Gravity on a circle of latitude.
Definition: GravityCircle.hpp:41
GeographicLib::GravityCircle::Gravity
Math::real Gravity(real lon, real &gx, real &gy, real &gz) const
Definition: GravityCircle.cpp:51
GeographicLib::GravityCircle::Disturbance
Math::real Disturbance(real lon, real &deltax, real &deltay, real &deltaz) const
Definition: GravityCircle.cpp:61
GeographicLib::GravityCircle::GeoidHeight
Math::real GeoidHeight(real lon) const
Definition: GravityCircle.cpp:71
GeographicLib::GravityCircle::SphericalAnomaly
void SphericalAnomaly(real lon, real &Dg01, real &xi, real &eta) const
Definition: GravityCircle.cpp:81
GeographicLib::GravityModel
Model of the earth's gravity field.
Definition: GravityModel.hpp:83
GeographicLib::GravityModel::Disturbance
Math::real Disturbance(real lat, real lon, real h, real &deltax, real &deltay, real &deltaz) const
Definition: GravityModel.cpp:312
GeographicLib::GravityModel::SphericalAnomaly
void SphericalAnomaly(real lat, real lon, real h, real &Dg01, real &xi, real &eta) const
Definition: GravityModel.cpp:264
GeographicLib::GravityModel::Circle
GravityCircle Circle(real lat, real h, unsigned caps=ALL) const
Definition: GravityModel.cpp:322
GeographicLib::GravityModel::GeoidHeight
Math::real GeoidHeight(real lat, real lon) const
Definition: GravityModel.cpp:290
GeographicLib::GravityModel::GravityModelName
const std::string & GravityModelName() const
Definition: GravityModel.hpp:463
GeographicLib::GravityModel::Gravity
Math::real Gravity(real lat, real lon, real h, real &gx, real &gy, real &gz) const
Definition: GravityModel.cpp:304
GeographicLib::GravityModel::GravityFile
const std::string & GravityFile() const
Definition: GravityModel.hpp:457
GeographicLib::GravityModel::Description
const std::string & Description() const
Definition: GravityModel.hpp:447
GeographicLib::GravityModel::DateTime
const std::string & DateTime() const
Definition: GravityModel.hpp:452
GeographicLib::Math::real
double real
Definition: Math.hpp:100
GeographicLib
Namespace for GeographicLib.
Definition: Accumulator.cpp:12