void setupGeoMagWorkspace(void)
{
uint8_t index;
uint16_t nMax = 12;
uint16_t numTerms;
///////////////////////////////////
numTerms = CALCULATE_NUMTERMS(nMax);
magneticModel = MAG_AllocateModelMemory(numTerms);
///////////////////////////////////
magneticModel->nMax = nMax;
magneticModel->nMaxSecVar = nMax;
magneticModel->epoch = 2010.0f;
strncpy(magneticModel->ModelName, "WMM-2010 11/20/2009\0", sizeof(magneticModel->ModelName));
magneticModel->Main_Field_Coeff_G[0] = 0.0f;
magneticModel->Main_Field_Coeff_H[0] = 0.0f;
magneticModel->Secular_Var_Coeff_G[0] = 0.0f;
magneticModel->Secular_Var_Coeff_H[0] = 0.0f;
for ( index = 1; index < 91; index++)
{
magneticModel->Main_Field_Coeff_G[index] = wmmCoefficients[index - 1][0]; // gnm
magneticModel->Main_Field_Coeff_H[index] = wmmCoefficients[index - 1][1]; // hnm
magneticModel->Secular_Var_Coeff_G[index] = wmmCoefficients[index - 1][2]; // dgnm
magneticModel->Secular_Var_Coeff_H[index] = wmmCoefficients[index - 1][3]; // dhnm
}
magneticModel->CoefficientFileEndDate = magneticModel->epoch + 5.0f;
///////////////////////////////////
numTerms = ((nMax + 1) * (nMax + 2) / 2);
timedMagneticModel = MAG_AllocateModelMemory(numTerms);
///////////////////////////////////
// Set WGS-84 parameters
ellipsoid.a = 6378.137f; // semi-major axis of the ellipsoid in km
ellipsoid.b = 6356.7523142f; // semi-minor axis of the ellipsoid in km
ellipsoid.fla = 1.0f / 298.257223563f; // flattening
ellipsoid.eps = sqrt(1.0f - (ellipsoid.b * ellipsoid.b) / (ellipsoid.a * ellipsoid.a)); // first eccentricity
ellipsoid.epssq = (ellipsoid.eps * ellipsoid.eps); // first eccentricity squared
ellipsoid.re = 6371.2f; // earth's radius in km
///////////////////////////////////
}
int main()
{
MAGtype_MagneticModel * MagneticModels[1], *TimedMagneticModel;
MAGtype_Ellipsoid Ellip;
MAGtype_CoordSpherical CoordSpherical;
MAGtype_CoordGeodetic CoordGeodetic;
MAGtype_Date UserDate;
MAGtype_GeoMagneticElements GeoMagneticElements;
MAGtype_Geoid Geoid;
char ans[20], b;
char filename[] = "WMM.COF";
char VersionDate_Large[] = "$Date: 2012-04-20 14:59:13 -0600 (Fri, 20 Apr 2012) $";
char VersionDate[12];
int NumTerms, Flag = 1, nMax = 0;
int epochs = 1;
/* Memory allocation */
strncpy(VersionDate, VersionDate_Large + 39, 11);
VersionDate[11] = '\0';
MAG_robustReadMagModels(filename, &MagneticModels, epochs);
if(nMax < MagneticModels[0]->nMax) nMax = MagneticModels[0]->nMax;
NumTerms = ((nMax + 1) * (nMax + 2) / 2);
TimedMagneticModel = MAG_AllocateModelMemory(NumTerms); /* For storing the time modified WMM Model parameters */
if(MagneticModels[0] == NULL || TimedMagneticModel == NULL)
{
MAG_Error(2);
}
MAG_SetDefaults(&Ellip, &Geoid); /* Set default values and constants */
/* Check for Geographic Poles */
//MAG_InitializeGeoid(&Geoid); /* Read the Geoid file */
/* Set EGM96 Geoid parameters */
Geoid.GeoidHeightBuffer = GeoidHeightBuffer;
Geoid.Geoid_Initialized = 1;
/* Set EGM96 Geoid parameters END */
b = MAG_GeomagIntroduction_WMM(MagneticModels[0], VersionDate);
while(Flag == 1 && b != 'x')
{
if(MAG_GetUserInput(MagneticModels[0], &Geoid, &CoordGeodetic, &UserDate) == 1) /*Get User Input */
{
MAG_GeodeticToSpherical(Ellip, CoordGeodetic, &CoordSpherical); /*Convert from geodetic to Spherical Equations: 17-18, WMM Technical report*/
MAG_TimelyModifyMagneticModel(UserDate, MagneticModels[0], TimedMagneticModel); /* Time adjust the coefficients, Equation 19, WMM Technical report */
MAG_Geomag(Ellip, CoordSpherical, CoordGeodetic, TimedMagneticModel, &GeoMagneticElements); /* Computes the geoMagnetic field elements and their time change*/
MAG_CalculateGridVariation(CoordGeodetic, &GeoMagneticElements);
MAG_PrintUserData(GeoMagneticElements, CoordGeodetic, UserDate, TimedMagneticModel, &Geoid); /* Print the results */
}
printf("\n\n Do you need more point data ? (y or n) \n ");
fgets(ans, 20, stdin);
switch(ans[0]) {
case 'Y':
case 'y':
Flag = 1;
break;
case 'N':
case 'n':
Flag = 0;
break;
default:
Flag = 0;
break;
}
}
MAG_FreeMagneticModelMemory(TimedMagneticModel);
MAG_FreeMagneticModelMemory(MagneticModels[0]);
return 0;
}
