Source file for the World Magnetic Model This is a port of code available from the US NOAA. More...

#include "openpilot.h"
#include "physical_constants.h"
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include <stdint.h>
#include "WorldMagModel.h"
#include "WMMInternal.h"

Functions
int	WMM_Initialize ()

int	WMM_GetMagVector (float Lat, float Lon, float AltEllipsoid, uint16_t Month, uint16_t Day, uint16_t Year, float B[3])

int	WMM_Geomag (WMMtype_CoordSpherical CoordSpherical, WMMtype_CoordGeodetic CoordGeodetic, WMMtype_GeoMagneticElements *GeoMagneticElements)

int	WMM_ComputeSphericalHarmonicVariables (WMMtype_CoordSpherical CoordSpherical, uint16_t nMax, WMMtype_SphericalHarmonicVariables SphVariables)

int	WMM_AssociatedLegendreFunction (WMMtype_CoordSpherical CoordSpherical, uint16_t nMax, WMMtype_LegendreFunction LegendreFunction)

int	WMM_Summation (WMMtype_LegendreFunction LegendreFunction, WMMtype_SphericalHarmonicVariables SphVariables, WMMtype_CoordSpherical CoordSpherical, WMMtype_MagneticResults MagneticResults)

int	WMM_SecVarSummation (WMMtype_LegendreFunction LegendreFunction, WMMtype_SphericalHarmonicVariables SphVariables, WMMtype_CoordSpherical CoordSpherical, WMMtype_MagneticResults MagneticResults)

int	WMM_RotateMagneticVector (WMMtype_CoordSpherical , WMMtype_CoordGeodetic CoordGeodetic, WMMtype_MagneticResults MagneticResultsSph, WMMtype_MagneticResults MagneticResultsGeo)

int	WMM_CalculateGeoMagneticElements (WMMtype_MagneticResults MagneticResultsGeo, WMMtype_GeoMagneticElements GeoMagneticElements)

int	WMM_CalculateSecularVariation (WMMtype_MagneticResults MagneticVariation, WMMtype_GeoMagneticElements MagneticElements)

int	WMM_PcupHigh (float Pcup, float dPcup, float x, uint16_t nMax)

int	WMM_PcupLow (float Pcup, float dPcup, float x, uint16_t nMax)

int	WMM_SummationSpecial (WMMtype_SphericalHarmonicVariables SphVariables, WMMtype_CoordSpherical CoordSpherical, WMMtype_MagneticResults *MagneticResults)

int	WMM_SecVarSummationSpecial (WMMtype_SphericalHarmonicVariables SphVariables, WMMtype_CoordSpherical CoordSpherical, WMMtype_MagneticResults *MagneticResults)

float	WMM_get_main_field_coeff_g (uint16_t index)
	Comput the MainFieldCoeffH accounting for the date. More...

float	WMM_get_main_field_coeff_h (uint16_t index)

float	WMM_get_secular_var_coeff_g (uint16_t index)

float	WMM_get_secular_var_coeff_h (uint16_t index)

int	WMM_DateToYear (uint16_t month, uint16_t day, uint16_t year)

int	WMM_GeodeticToSpherical (WMMtype_CoordGeodetic CoordGeodetic, WMMtype_CoordSpherical CoordSpherical)

Variables
static const float	CoeffFile [91][6] = COEFFS_FROM_NASA

static WMMtype_Ellipsoid	Ellip

static WMMtype_MagneticModel	MagneticModel

static float	decimal_date

Detailed Description

Source file for the World Magnetic Model This is a port of code available from the US NOAA.

Author: The OpenPilot Team, http://www.openpilot.org Copyright (C) 2010.; Tau Labs, http://taulabs.org, Copyright (C) 2013-2014; dRonin, http://dronin.org Copyright (C) 2015 The hard coded coefficients should be valid until 2020.

Updated coeffs from .. http://www.ngdc.noaa.gov/geomag/WMM/wmm_ddownload.shtml

NASA C source code .. http://www.ngdc.noaa.gov/geomag/WMM/wmm_wdownload.shtml

Major changes include:

No geoid model (altitude must be geodetic WGS-84)
Floating point calculation (not double precision)
Hard coded coefficients for model
Elimination of user interface
Elimination of dynamic memory allocation

See Also: The GNU Public License (GPL) Version 3

Definition in file WorldMagModel.c.

Functions

Variables

Detailed Description