int main(int argc, char** argv)
{
int status = 0;
oskar::OptionParser opt("oskar_convert_geodetic_to_ecef",
oskar_version_string());
opt.set_description("Converts geodetic longitude/latitude/altitude to "
"Cartesian ECEF coordinates. Assumes WGS84 ellipsoid.");
opt.add_required("input file", "Path to file containing input coordinates. "
"Angles must be in degrees.");
if (!opt.check_options(argc, argv))
return OSKAR_FAIL;
const char* filename = opt.get_arg();
// Load the input file.
oskar_Mem *lon = oskar_mem_create(OSKAR_DOUBLE, OSKAR_CPU, 0, &status);
oskar_Mem *lat = oskar_mem_create(OSKAR_DOUBLE, OSKAR_CPU, 0, &status);
oskar_Mem *alt = oskar_mem_create(OSKAR_DOUBLE, OSKAR_CPU, 0, &status);
size_t num_points = oskar_mem_load_ascii(filename, 3, &status,
lon, "", lat, "", alt, "0.0");
oskar_mem_scale_real(lon, M_PI / 180.0, &status);
oskar_mem_scale_real(lat, M_PI / 180.0, &status);
// Convert coordinates.
oskar_Mem *x = oskar_mem_create(OSKAR_DOUBLE, OSKAR_CPU,
num_points, &status);
oskar_Mem *y = oskar_mem_create(OSKAR_DOUBLE, OSKAR_CPU,
num_points, &status);
oskar_Mem *z = oskar_mem_create(OSKAR_DOUBLE, OSKAR_CPU,
num_points, &status);
oskar_convert_geodetic_spherical_to_ecef(num_points,
oskar_mem_double_const(lon, &status),
oskar_mem_double_const(lat, &status),
oskar_mem_double_const(alt, &status),
oskar_mem_double(x, &status),
oskar_mem_double(y, &status),
oskar_mem_double(z, &status));
// Print converted coordinates.
oskar_mem_save_ascii(stdout, 3, num_points, &status, x, y, z);
// Clean up.
oskar_mem_free(lon, &status);
oskar_mem_free(lat, &status);
oskar_mem_free(alt, &status);
oskar_mem_free(x, &status);
oskar_mem_free(y, &status);
oskar_mem_free(z, &status);
if (status)
{
oskar_log_error(0, oskar_get_error_string(status));
return status;
}
return 0;
}
double oskar_evaluate_diurnal_aberration(double lon_rad, double lat_rad,
double height_m, double era_rad, double pm_x_rad, double pm_y_rad,
double s_prime)
{
double sin_sp, cos_sp, sin_xp, cos_xp, sin_yp, cos_yp, sin_era, cos_era;
double a, b, x, y, z, vx, vy;
/* Earth rotation rate in rad per second of UT1. */
const double omega_earth = 1.00273781191135448 * 2.0 * M_PI / 86400.0;
/* Transform geodetic (longitude, latitude, altitude) to geocentric XYZ. */
oskar_convert_geodetic_spherical_to_ecef(1,
&lon_rad, &lat_rad, &height_m, &x, &y, &z);
/* Calculate elements of polar motion matrix. */
sin_sp = sin(s_prime);
cos_sp = cos(s_prime);
sin_xp = sin(pm_x_rad);
cos_xp = cos(pm_x_rad);
sin_yp = sin(pm_y_rad);
cos_yp = cos(pm_y_rad);
/* Matrix-vector multiplication. */
a = x * cos_sp * cos_xp +
y * (cos_yp * sin_sp + cos_sp * sin_xp * sin_yp) +
z * (cos_sp * cos_yp * sin_xp - sin_sp * sin_yp);
b = x * -cos_xp * sin_sp +
y * (cos_sp * cos_yp - sin_sp * sin_xp * sin_yp) +
z * (-cos_sp * sin_yp - cos_yp * sin_sp * sin_xp);
/* Get velocity components. */
sin_era = sin(era_rad);
cos_era = cos(era_rad);
vx = omega_earth * (-sin_era * a - cos_era * b);
vy = omega_earth * ( cos_era * a - sin_era * b);
/* Return magnitude of diurnal aberration vector. */
return sqrt(vx*vx + vy*vy) / 299792458.0;
}
