com.luciad.format.magneticnorth

LuciadLightspeedClass TLcdIGRFMagneticNorthMap

java.lang.Object

com.luciad.format.magneticnorth.TLcdIGRFMagneticNorthMap

All Implemented Interfaces:

ILcdMagneticNorthMap, ILcdInputStreamFactoryCapable

public class TLcdIGRFMagneticNorthMap
extends Object
implements ILcdInputStreamFactoryCapable

This class maps the declination, inclination and total intensity of the magnetic north vector to a given point and date.

Be sure to use the same TLcdIGRFMagneticNorthMap for successive calculations since it performs caching.

The model used for the calculations has a limited life span. If you try to perform calculations outside this lifespan, an exception will be thrown.

The user of this class is responsible for setting the data file name of the model to use. See TLcdIGRFModelDecoder for more information about the supported data files.

Check out http://www.ngdc.noaa.gov/geomag/geomag.shtml for more info about the used terms.
Check out http://www.ngdc.noaa.gov/IAGA/vmod/igrf.html for more information about the used model.

Field Summary

Fields

Modifier and Type	Field and Description
protected static int	DECLINATION
protected static int	INCLINATION
protected static int	TOTAL_INTENSITY

Constructor Summary

Constructors

Constructor and Description
TLcdIGRFMagneticNorthMap() Constructs a new TLcdIGRFMagneticNorthMap.
TLcdIGRFMagneticNorthMap(String aDataFileName) Constructs a new TLcdIGRFMagneticNorthMap ready to use.

Method Summary

Modifier and Type	Method and Description
Object	clone()
static float	convertCalendarToDecimalTime(Calendar aTime) Converts a Calendar to a decimal year format.
static Calendar	convertDecimalTimeToCalendar(float aDecimalTime) Converts a decimal year format to a Calendar.
Calendar	getBeginValidDate() Return the first date value for which this map can retrieve magnetic north.
String	getDataFileName() Return the file name of the data file used to base the calculations on.
Calendar	getDate() Returns the current date set to this map.
Calendar	getEndValidDate() Return the last date value for which this map can retrieve magnetic north.
ILcdInputStreamFactory	getInputStreamFactory() Returns the input stream factory to load the data.
String	getModelName() Returns the name of the model.
String	getShortModelName() Returns the abbreviated model name.
Calendar	getValidDateClosestToToday()
boolean	isValidDate(Calendar aDate) Checks whether the given date is a valid date for this map.
float	retrieveDeclinationAt(ILcdPoint aPoint) Given a point (and implicitly a time value via setDate()), this method calculates the declination of the magnetic north vector.
float	retrieveInclinationAt(ILcdPoint aPoint) Given a point (and implicitly a time value via setDate()), this method calculates the inclination of the magnetic north vector.
float	retrieveTotalIntensityAt(ILcdPoint aPoint) Given a point (and implicitly a time value via setDate()), this method calculates the total intensity of the magnetic north vector.
void	setDataFileName(String aDataFileName) Sets the file name of the data file to be used.
void	setDate(Calendar aDate) Sets the date to retrieve the magnetic north at.
void	setInputStreamFactory(ILcdInputStreamFactory aInputStreamFactory) Sets the input stream factory to load the data.

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DECLINATION

protected static final int DECLINATION

See Also:

Constant Field Values

INCLINATION

protected static final int INCLINATION

See Also:

Constant Field Values

TOTAL_INTENSITY

protected static final int TOTAL_INTENSITY

See Also:

Constant Field Values

Constructor Detail

TLcdIGRFMagneticNorthMap

public TLcdIGRFMagneticNorthMap()

Constructs a new TLcdIGRFMagneticNorthMap. You have to set the data file before it can be fully used.

TLcdIGRFMagneticNorthMap

public TLcdIGRFMagneticNorthMap(String aDataFileName)

Constructs a new TLcdIGRFMagneticNorthMap ready to use.

Parameters:

aDataFileName - The file name of the data file containing the data about the igrf model

Method Detail

getDataFileName

public String getDataFileName()

Return the file name of the data file used to base the calculations on.

Returns:

The file name of the data file used to base the calculations on

See Also:

setDataFileName(java.lang.String)

setDataFileName

public void setDataFileName(String aDataFileName)

Sets the file name of the data file to be used.

Parameters:

aDataFileName - The file name relative to the classpath

See Also:

getDataFileName()

getModelName

public String getModelName()

Description copied from interface: ILcdMagneticNorthMap

Returns the name of the model.

Specified by:

getModelName in interface ILcdMagneticNorthMap

Returns:

the name of the model

See Also:

ILcdMagneticNorthMap

getShortModelName

public String getShortModelName()

Description copied from interface: ILcdMagneticNorthMap

Returns the abbreviated model name.

Specified by:

getShortModelName in interface ILcdMagneticNorthMap

Returns:

the abbreviated model name

See Also:

ILcdMagneticNorthMap

retrieveDeclinationAt

public float retrieveDeclinationAt(ILcdPoint aPoint)

Description copied from interface: ILcdMagneticNorthMap

Given a point (and implicitly a time value via setDate()), this method calculates the declination of the magnetic north vector.

Specified by:

retrieveDeclinationAt in interface ILcdMagneticNorthMap

Parameters:

aPoint - The point on the globe, the reference is World Geodetic System 1984 (WGS 84)

Returns:

the declination in degrees at the given point

retrieveInclinationAt

public float retrieveInclinationAt(ILcdPoint aPoint)

Description copied from interface: ILcdMagneticNorthMap

Given a point (and implicitly a time value via setDate()), this method calculates the inclination of the magnetic north vector.

Specified by:

retrieveInclinationAt in interface ILcdMagneticNorthMap

Parameters:

aPoint - The point on the globe, the reference is World Geodetic System 1984 (WGS 84)

Returns:

the inclination in degrees at the given point

retrieveTotalIntensityAt

public float retrieveTotalIntensityAt(ILcdPoint aPoint)

Description copied from interface: ILcdMagneticNorthMap

Given a point (and implicitly a time value via setDate()), this method calculates the total intensity of the magnetic north vector.

Specified by:

retrieveTotalIntensityAt in interface ILcdMagneticNorthMap

Parameters:

aPoint - The point on the globe, the reference is World Geodetic System 1984 (WGS 84)

Returns:

the total intensity in nanoTesla (nT) at the given point

isValidDate

public boolean isValidDate(Calendar aDate)

Description copied from interface: ILcdMagneticNorthMap

Checks whether the given date is a valid date for this map.

Specified by:

isValidDate in interface ILcdMagneticNorthMap

Parameters:

aDate - the date to check the validity for.

Returns:

true if getBeginValidDate() <= aDate <= getEndValidDate(), false otherwise.

getBeginValidDate

public Calendar getBeginValidDate()

Description copied from interface: ILcdMagneticNorthMap

Return the first date value for which this map can retrieve magnetic north.

Specified by:

getBeginValidDate in interface ILcdMagneticNorthMap

Returns:

the first date value for which this map can retrieve magnetic north

getEndValidDate

public Calendar getEndValidDate()

Description copied from interface: ILcdMagneticNorthMap

Return the last date value for which this map can retrieve magnetic north.

Specified by:

getEndValidDate in interface ILcdMagneticNorthMap

Returns:

the last date value for which this map can retrieve magnetic north

setDate

public void setDate(Calendar aDate)

Description copied from interface: ILcdMagneticNorthMap

Sets the date to retrieve the magnetic north at.

Specified by:

setDate in interface ILcdMagneticNorthMap

Parameters:

aDate - The date, isValidDate(aDate) must be true.

See Also:

ILcdMagneticNorthMap.getDate()

getDate

public Calendar getDate()

Description copied from interface: ILcdMagneticNorthMap

Returns the current date set to this map.

Specified by:

getDate in interface ILcdMagneticNorthMap

Returns:

The current date set to this map.

See Also:

ILcdMagneticNorthMap.setDate(java.util.Calendar)

clone

public Object clone()
             throws CloneNotSupportedException

Specified by:

clone in interface ILcdMagneticNorthMap

Throws:

CloneNotSupportedException

getInputStreamFactory

public ILcdInputStreamFactory getInputStreamFactory()

Returns the input stream factory to load the data.

Specified by:

getInputStreamFactory in interface ILcdInputStreamFactoryCapable

Returns:

the input stream factory to load the data.

See Also:

setInputStreamFactory(com.luciad.io.ILcdInputStreamFactory)

setInputStreamFactory

public void setInputStreamFactory(ILcdInputStreamFactory aInputStreamFactory)

Sets the input stream factory to load the data.

Specified by:

setInputStreamFactory in interface ILcdInputStreamFactoryCapable

Parameters:

aInputStreamFactory - an InputStream factory that creates input streams to load the magnetic north data.

See Also:

getInputStreamFactory()

getValidDateClosestToToday

public Calendar getValidDateClosestToToday()

convertCalendarToDecimalTime

public static float convertCalendarToDecimalTime(Calendar aTime)

Converts a Calendar to a decimal year format. Only uses year, month and day. Hours and seconds are ignored.

convertDecimalTimeToCalendar

public static Calendar convertDecimalTimeToCalendar(float aDecimalTime)

Converts a decimal year format to a Calendar. Only uses year. Month, day, hours and seconds are ignored.