GeographicLib 1.52
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Gravity.cpp
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1/**
2 * \file Gravity.cpp
3 * \brief Command line utility for evaluating gravity fields
4 *
5 * Copyright (c) Charles Karney (2011-2020) <charles@karney.com> and licensed
6 * under the MIT/X11 License. For more information, see
7 * https://geographiclib.sourceforge.io/
8 *
9 * See the <a href="Gravity.1.html">man page</a> for usage information.
10 **********************************************************************/
11
12#include <iostream>
13#include <string>
14#include <sstream>
15#include <fstream>
18#include <GeographicLib/DMS.hpp>
20
21#if defined(_MSC_VER)
22// Squelch warnings about constant conditional expressions and potentially
23// uninitialized local variables
24# pragma warning (disable: 4127 4701)
25#endif
26
27#include "Gravity.usage"
28
29int main(int argc, const char* const argv[]) {
30 try {
31 using namespace GeographicLib;
32 typedef Math::real real;
33 Utility::set_digits();
34 bool verbose = false, longfirst = false;
35 std::string dir;
36 std::string model = GravityModel::DefaultGravityName();
37 std::string istring, ifile, ofile, cdelim;
38 char lsep = ';';
39 real lat = 0, h = 0;
40 bool circle = false;
41 int prec = -1, Nmax = -1, Mmax = -1;
42 enum {
43 GRAVITY = 0,
44 DISTURBANCE = 1,
45 ANOMALY = 2,
46 UNDULATION = 3,
47 };
48 unsigned mode = GRAVITY;
49 for (int m = 1; m < argc; ++m) {
50 std::string arg(argv[m]);
51 if (arg == "-n") {
52 if (++m == argc) return usage(1, true);
53 model = argv[m];
54 } else if (arg == "-d") {
55 if (++m == argc) return usage(1, true);
56 dir = argv[m];
57 } else if (arg == "-N") {
58 if (++m == argc) return usage(1, true);
59 try {
60 Nmax = Utility::val<int>(std::string(argv[m]));
61 if (Nmax < 0) {
62 std::cerr << "Maximum degree " << argv[m] << " is negative\n";
63 return 1;
64 }
65 }
66 catch (const std::exception&) {
67 std::cerr << "Precision " << argv[m] << " is not a number\n";
68 return 1;
69 }
70 } else if (arg == "-M") {
71 if (++m == argc) return usage(1, true);
72 try {
73 Mmax = Utility::val<int>(std::string(argv[m]));
74 if (Mmax < 0) {
75 std::cerr << "Maximum order " << argv[m] << " is negative\n";
76 return 1;
77 }
78 }
79 catch (const std::exception&) {
80 std::cerr << "Precision " << argv[m] << " is not a number\n";
81 return 1;
82 }
83 } else if (arg == "-G")
84 mode = GRAVITY;
85 else if (arg == "-D")
86 mode = DISTURBANCE;
87 else if (arg == "-A")
88 mode = ANOMALY;
89 else if (arg == "-H")
90 mode = UNDULATION;
91 else if (arg == "-c") {
92 if (m + 2 >= argc) return usage(1, true);
93 try {
94 using std::abs;
95 DMS::flag ind;
96 lat = DMS::Decode(std::string(argv[++m]), ind);
97 if (ind == DMS::LONGITUDE)
98 throw GeographicErr("Bad hemisphere letter on latitude");
99 if (!(abs(lat) <= 90))
100 throw GeographicErr("Latitude not in [-90d, 90d]");
101 h = Utility::val<real>(std::string(argv[++m]));
102 circle = true;
103 }
104 catch (const std::exception& e) {
105 std::cerr << "Error decoding argument of " << arg << ": "
106 << e.what() << "\n";
107 return 1;
108 }
109 } else if (arg == "-w")
110 longfirst = !longfirst;
111 else if (arg == "-p") {
112 if (++m == argc) return usage(1, true);
113 try {
114 prec = Utility::val<int>(std::string(argv[m]));
115 }
116 catch (const std::exception&) {
117 std::cerr << "Precision " << argv[m] << " is not a number\n";
118 return 1;
119 }
120 } else if (arg == "-v")
121 verbose = true;
122 else if (arg == "--input-string") {
123 if (++m == argc) return usage(1, true);
124 istring = argv[m];
125 } else if (arg == "--input-file") {
126 if (++m == argc) return usage(1, true);
127 ifile = argv[m];
128 } else if (arg == "--output-file") {
129 if (++m == argc) return usage(1, true);
130 ofile = argv[m];
131 } else if (arg == "--line-separator") {
132 if (++m == argc) return usage(1, true);
133 if (std::string(argv[m]).size() != 1) {
134 std::cerr << "Line separator must be a single character\n";
135 return 1;
136 }
137 lsep = argv[m][0];
138 } else if (arg == "--comment-delimiter") {
139 if (++m == argc) return usage(1, true);
140 cdelim = argv[m];
141 } else if (arg == "--version") {
142 std::cout << argv[0] << ": GeographicLib version "
143 << GEOGRAPHICLIB_VERSION_STRING << "\n";
144 return 0;
145 } else {
146 int retval = usage(!(arg == "-h" || arg == "--help"), arg != "--help");
147 if (arg == "-h")
148 std::cout<< "\nDefault gravity path = \""
149 << GravityModel::DefaultGravityPath()
150 << "\"\nDefault gravity name = \""
151 << GravityModel::DefaultGravityName()
152 << "\"\n";
153 return retval;
154 }
155 }
156
157 if (!ifile.empty() && !istring.empty()) {
158 std::cerr << "Cannot specify --input-string and --input-file together\n";
159 return 1;
160 }
161 if (ifile == "-") ifile.clear();
162 std::ifstream infile;
163 std::istringstream instring;
164 if (!ifile.empty()) {
165 infile.open(ifile.c_str());
166 if (!infile.is_open()) {
167 std::cerr << "Cannot open " << ifile << " for reading\n";
168 return 1;
169 }
170 } else if (!istring.empty()) {
171 std::string::size_type m = 0;
172 while (true) {
173 m = istring.find(lsep, m);
174 if (m == std::string::npos)
175 break;
176 istring[m] = '\n';
177 }
178 instring.str(istring);
179 }
180 std::istream* input = !ifile.empty() ? &infile :
181 (!istring.empty() ? &instring : &std::cin);
182
183 std::ofstream outfile;
184 if (ofile == "-") ofile.clear();
185 if (!ofile.empty()) {
186 outfile.open(ofile.c_str());
187 if (!outfile.is_open()) {
188 std::cerr << "Cannot open " << ofile << " for writing\n";
189 return 1;
190 }
191 }
192 std::ostream* output = !ofile.empty() ? &outfile : &std::cout;
193
194 switch (mode) {
195 case GRAVITY:
196 prec = std::min(16 + Math::extra_digits(), prec < 0 ? 5 : prec);
197 break;
198 case DISTURBANCE:
199 case ANOMALY:
200 prec = std::min(14 + Math::extra_digits(), prec < 0 ? 3 : prec);
201 break;
202 case UNDULATION:
203 default:
204 prec = std::min(12 + Math::extra_digits(), prec < 0 ? 4 : prec);
205 break;
206 }
207 int retval = 0;
208 try {
209 using std::isfinite;
210 const GravityModel g(model, dir, Nmax, Mmax);
211 if (circle) {
212 if (!isfinite(h))
213 throw GeographicErr("Bad height");
214 else if (mode == UNDULATION && h != 0)
215 throw GeographicErr("Height should be zero for geoid undulations");
216 }
217 if (verbose) {
218 std::cerr << "Gravity file: " << g.GravityFile() << "\n"
219 << "Name: " << g.GravityModelName() << "\n"
220 << "Description: " << g.Description() << "\n"
221 << "Date & Time: " << g.DateTime() << "\n";
222 }
223 unsigned mask = (mode == GRAVITY ? GravityModel::GRAVITY :
224 (mode == DISTURBANCE ? GravityModel::DISTURBANCE :
225 (mode == ANOMALY ? GravityModel::SPHERICAL_ANOMALY :
226 GravityModel::GEOID_HEIGHT))); // mode == UNDULATION
227 const GravityCircle c(circle ? g.Circle(lat, h, mask) : GravityCircle());
228 std::string s, eol, stra, strb;
229 std::istringstream str;
230 while (std::getline(*input, s)) {
231 try {
232 eol = "\n";
233 if (!cdelim.empty()) {
234 std::string::size_type m = s.find(cdelim);
235 if (m != std::string::npos) {
236 eol = " " + s.substr(m) + "\n";
237 s = s.substr(0, m);
238 }
239 }
240 str.clear(); str.str(s);
241 real lon;
242 if (circle) {
243 if (!(str >> strb))
244 throw GeographicErr("Incomplete input: " + s);
245 DMS::flag ind;
246 lon = DMS::Decode(strb, ind);
247 if (ind == DMS::LATITUDE)
248 throw GeographicErr("Bad hemisphere letter on " + strb);
249 } else {
250 if (!(str >> stra >> strb))
251 throw GeographicErr("Incomplete input: " + s);
252 DMS::DecodeLatLon(stra, strb, lat, lon, longfirst);
253 h = 0;
254 if (!(str >> h)) // h is optional
255 str.clear();
256 if (mode == UNDULATION && h != 0)
257 throw GeographicErr("Height must be zero for geoid heights");
258 }
259 if (str >> stra)
260 throw GeographicErr("Extra junk in input: " + s);
261 switch (mode) {
262 case GRAVITY:
263 {
264 real gx, gy, gz;
265 if (circle) {
266 c.Gravity(lon, gx, gy, gz);
267 } else {
268 g.Gravity(lat, lon, h, gx, gy, gz);
269 }
270 *output << Utility::str(gx, prec) << " "
271 << Utility::str(gy, prec) << " "
272 << Utility::str(gz, prec) << eol;
273 }
274 break;
275 case DISTURBANCE:
276 {
277 real deltax, deltay, deltaz;
278 if (circle) {
279 c.Disturbance(lon, deltax, deltay, deltaz);
280 } else {
281 g.Disturbance(lat, lon, h, deltax, deltay, deltaz);
282 }
283 // Convert to mGals
284 *output << Utility::str(deltax * 100000, prec) << " "
285 << Utility::str(deltay * 100000, prec) << " "
286 << Utility::str(deltaz * 100000, prec)
287 << eol;
288 }
289 break;
290 case ANOMALY:
291 {
292 real Dg01, xi, eta;
293 if (circle)
294 c.SphericalAnomaly(lon, Dg01, xi, eta);
295 else
296 g.SphericalAnomaly(lat, lon, h, Dg01, xi, eta);
297 Dg01 *= 100000; // Convert to mGals
298 xi *= 3600; // Convert to arcsecs
299 eta *= 3600;
300 *output << Utility::str(Dg01, prec) << " "
301 << Utility::str(xi, prec) << " "
302 << Utility::str(eta, prec) << eol;
303 }
304 break;
305 case UNDULATION:
306 default:
307 {
308 real N = circle ? c.GeoidHeight(lon) : g.GeoidHeight(lat, lon);
309 *output << Utility::str(N, prec) << eol;
310 }
311 break;
312 }
313 }
314 catch (const std::exception& e) {
315 *output << "ERROR: " << e.what() << "\n";
316 retval = 1;
317 }
318 }
319 }
320 catch (const std::exception& e) {
321 std::cerr << "Error reading " << model << ": " << e.what() << "\n";
322 retval = 1;
323 }
324 return retval;
325 }
326 catch (const std::exception& e) {
327 std::cerr << "Caught exception: " << e.what() << "\n";
328 return 1;
329 }
330 catch (...) {
331 std::cerr << "Caught unknown exception\n";
332 return 1;
333 }
334}
Header for GeographicLib::DMS class.
GeographicLib::Math::real real
Definition: GeodSolve.cpp:31
Header for GeographicLib::GravityCircle class.
Header for GeographicLib::GravityModel class.
int main(int argc, const char *const argv[])
Definition: Gravity.cpp:29
Header for GeographicLib::Utility class.
Exception handling for GeographicLib.
Definition: Constants.hpp:315
Gravity on a circle of latitude.
Math::real Gravity(real lon, real &gx, real &gy, real &gz) const
Math::real Disturbance(real lon, real &deltax, real &deltay, real &deltaz) const
Math::real GeoidHeight(real lon) const
void SphericalAnomaly(real lon, real &Dg01, real &xi, real &eta) const
Model of the earth's gravity field.
Math::real Disturbance(real lat, real lon, real h, real &deltax, real &deltay, real &deltaz) const
void SphericalAnomaly(real lat, real lon, real h, real &Dg01, real &xi, real &eta) const
GravityCircle Circle(real lat, real h, unsigned caps=ALL) const
Math::real GeoidHeight(real lat, real lon) const
const std::string & GravityModelName() const
Math::real Gravity(real lat, real lon, real h, real &gx, real &gy, real &gz) const
const std::string & GravityFile() const
const std::string & Description() const
const std::string & DateTime() const
Namespace for GeographicLib.
Definition: Accumulator.cpp:12