GeomagneticField

Kotlin |Java

public class GeomagneticField
extends Object

java.lang.Object
↳	android.hardware.GeomagneticField

Estimates magnetic field at a given point on Earth, and in particular, to compute the magnetic declination from true north.

This uses the World Magnetic Model produced by the United States National Geospatial-Intelligence Agency. More details about the model can be found at http://www.ngdc.noaa.gov/geomag/WMM/DoDWMM.shtml. This class currently uses WMM-2020 which is valid until 2025, but should produce acceptable results for several years after that. Future versions of Android may use a newer version of the model.

Summary

Public constructors
`GeomagneticField(float gdLatitudeDeg, float gdLongitudeDeg, float altitudeMeters, long timeMillis)` Estimate the magnetic field at a given point and time.

Public methods
`float`	`getDeclination()`
`float`	`getFieldStrength()`
`float`	`getHorizontalStrength()`
`float`	`getInclination()`
`float`	`getX()`
`float`	`getY()`
`float`	`getZ()`

Inherited methods

From class


        
          java.lang.Object

`Object`	`clone()` Creates and returns a copy of this object.
`boolean`	`equals(Object obj)` Indicates whether some other object is "equal to" this one.
`void`	`finalize()` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
`final Class<?>`	`getClass()` Returns the runtime class of this `Object`.
`int`	`hashCode()` Returns a hash code value for the object.
`final void`	`notify()` Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()` Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()` Returns a string representation of the object.
`final void`	`wait(long timeoutMillis, int nanos)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis)` Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait()` Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public constructors

GeomagneticField

Added in API level 3

public GeomagneticField (float gdLatitudeDeg, 
                float gdLongitudeDeg, 
                float altitudeMeters, 
                long timeMillis)

Estimate the magnetic field at a given point and time.

Parameters
`gdLatitudeDeg`	`float`: Latitude in WGS84 geodetic coordinates -- positive is east.
`gdLongitudeDeg`	`float`: Longitude in WGS84 geodetic coordinates -- positive is north.
`altitudeMeters`	`float`: Altitude in WGS84 geodetic coordinates, in meters.
`timeMillis`	`long`: Time at which to evaluate the declination, in milliseconds since January 1, 1970. (approximate is fine -- the declination changes very slowly).

Public methods

getDeclination

Added in API level 3

public float getDeclination ()

Returns
`float`	The declination of the horizontal component of the magnetic field from true north, in degrees (i.e. positive means the magnetic field is rotated east that much from true north).

getFieldStrength

Added in API level 3

public float getFieldStrength ()

Returns
`float`	Total field strength in nanoteslas.

getHorizontalStrength

Added in API level 3

public float getHorizontalStrength ()

Returns
`float`	Horizontal component of the field strength in nanoteslas.

getInclination

Added in API level 3

public float getInclination ()

Returns
`float`	The inclination of the magnetic field in degrees -- positive means the magnetic field is rotated downwards.

getX

Added in API level 3

public float getX ()

Returns
`float`	The X (northward) component of the magnetic field in nanoteslas.

getY

Added in API level 3

public float getY ()

Returns
`float`	The Y (eastward) component of the magnetic field in nanoteslas.

getZ

Added in API level 3

public float getZ ()

Returns
`float`	The Z (downward) component of the magnetic field in nanoteslas.