Package org.orekit.forces.gravity.potential

Class PotentialCoefficientsReader

java.lang.Object

org.orekit.forces.gravity.potential.PotentialCoefficientsReader

All Implemented Interfaces:

DataLoader

Direct Known Subclasses:

EGMFormatReader, GRGSFormatReader, ICGEMFormatReader, SHMFormatReader

public abstract class PotentialCoefficientsReader
extends Object
implements DataLoader

This abstract class represents a Gravitational Potential Coefficients file reader.

As it exits many different coefficients models and containers this interface represents all the methods that should be implemented by a reader. The proper way to use this interface is to call the GravityFieldFactory which will determine which reader to use with the selected potential coefficients file.

Author:

Fabien Maussion

See Also:

GravityFieldFactory

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	PotentialCoefficientsReader(String supportedNames, boolean missingCoefficientsAllowed)	Simple constructor.

Method Summary

Modifier and Type	Method	Description
protected static double[]	buildRow(int degree, int order, double value)	Build a coefficients row.
protected static double[][]	buildTriangularArray(int degree, int order, double value)	Build a coefficients triangular array.
protected void	extendListOfLists(List<List<Double>> list, int degree, int order, double value)	Extend a list of lists of coefficients if needed.
protected double	getAe()	Get the central body reference radius.
protected org.orekit.forces.gravity.potential.ConstantSphericalHarmonics	getConstantProvider(boolean wantNormalized, int degree, int order)	Get a time-independent provider for read spherical harmonics coefficients.
int	getMaxAvailableDegree()	Get the maximal degree available in the last file parsed.
int	getMaxAvailableOrder()	Get the maximal order available in the last file parsed.
int	getMaxParseDegree()	Get the degree limit for the next file parsing.
int	getMaxParseOrder()	Get the order limit for the next file parsing.
protected double	getMu()	Get the central body attraction coefficient.
abstract RawSphericalHarmonicsProvider	getProvider(boolean wantNormalized, int degree, int order)	Get a provider for read spherical harmonics coefficients.
String	getSupportedNames()	Get the regular expression for supported files names.
protected TideSystem	getTideSystem()	Get the TideSystem used in the gravity field.
abstract void	loadData(InputStream input, String name)	Load data from a stream.
boolean	missingCoefficientsAllowed()	Check if missing coefficients are allowed in the input data.
protected void	parseCoefficient(String field, double[][] array, int i, int j, String cName, String name)	Parse a coefficient.
protected void	parseCoefficient(String field, List<List<Double>> list, int i, int j, String cName, String name)	Parse a coefficient.
protected static double	parseDouble(String string)	Parse a double from a string.
protected static void	rescale(double scale, boolean normalizedOrigin, double[][] originC, double[][] originS, boolean wantNormalized, double[][] rescaledC, double[][] rescaledS)	Rescale coefficients arrays.
protected void	setAe(double ae)	Set the central body reference radius.
void	setMaxParseDegree(int maxParseDegree)	Set the degree limit for the next file parsing.
void	setMaxParseOrder(int maxParseOrder)	Set the order limit for the next file parsing.
protected void	setMu(double mu)	Set the central body attraction coefficient.
protected void	setRawCoefficients(boolean rawNormalized, double[][] c, double[][] s, String name)	Set the tesseral-sectorial coefficients matrix.
protected void	setReadComplete(boolean readComplete)	Set the indicator for completed read.
protected void	setTideSystem(TideSystem tideSystem)	Set the TideSystem used in the gravity field.
boolean	stillAcceptsData()	Check if the loader still accepts new data.
protected double[][]	toArray(List<List<Double>> list)	Convert a list of list into an array.

Methods inherited from class java.lang.Object

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

Constructor Detail

PotentialCoefficientsReader

protected PotentialCoefficientsReader(String supportedNames,
                                      boolean missingCoefficientsAllowed)

Simple constructor.

Build an uninitialized reader.

Parameters:

supportedNames - regular expression for supported files names

missingCoefficientsAllowed - allow missing coefficients in the input data

Method Detail

getSupportedNames

public String getSupportedNames()

Get the regular expression for supported files names.

Returns:

regular expression for supported files names

missingCoefficientsAllowed

public boolean missingCoefficientsAllowed()

Check if missing coefficients are allowed in the input data.

Returns:

true if missing coefficients are allowed in the input data

setMaxParseDegree

public void setMaxParseDegree(int maxParseDegree)

Set the degree limit for the next file parsing.

Parameters:

maxParseDegree - maximal degree to parse (may be safely set to Integer.MAX_VALUE to parse all available coefficients)

Since:

6.0

getMaxParseDegree

public int getMaxParseDegree()

Get the degree limit for the next file parsing.

Returns:

degree limit for the next file parsing

Since:

6.0

setMaxParseOrder

public void setMaxParseOrder(int maxParseOrder)

Set the order limit for the next file parsing.

Parameters:

maxParseOrder - maximal order to parse (may be safely set to Integer.MAX_VALUE to parse all available coefficients)

Since:

6.0

getMaxParseOrder

public int getMaxParseOrder()

Get the order limit for the next file parsing.

Returns:

order limit for the next file parsing

Since:

6.0

stillAcceptsData

public boolean stillAcceptsData()

Check if the loader still accepts new data.

This method is used to speed up data loading by interrupting crawling the data sets as soon as a loader has found the data it was waiting for. For loaders that can merge data from any number of sources (for example JPL ephemerides or Earth Orientation Parameters that are split among several files), this method should always return true to make sure no data is left over.

Specified by:

stillAcceptsData in interface DataLoader

Returns:

true while the loader still accepts new data

setReadComplete

protected void setReadComplete(boolean readComplete)

Set the indicator for completed read.

Parameters:

readComplete - if true, a gravity field has been completely read

setAe

protected void setAe(double ae)

Set the central body reference radius.

Parameters:

ae - central body reference radius

getAe

protected double getAe()

Get the central body reference radius.

Returns:

central body reference radius

setMu

protected void setMu(double mu)

Set the central body attraction coefficient.

Parameters:

mu - central body attraction coefficient

getMu

protected double getMu()

Get the central body attraction coefficient.

Returns:

central body attraction coefficient

setTideSystem

protected void setTideSystem(TideSystem tideSystem)

Set the TideSystem used in the gravity field.

Parameters:

tideSystem - tide system used in the gravity field

getTideSystem

protected TideSystem getTideSystem()

Get the TideSystem used in the gravity field.

Returns:

tide system used in the gravity field

setRawCoefficients

protected void setRawCoefficients(boolean rawNormalized,
                                  double[][] c,
                                  double[][] s,
                                  String name)
                           throws OrekitException

Set the tesseral-sectorial coefficients matrix.

Parameters:

rawNormalized - if true, raw coefficients are normalized

c - raw tesseral-sectorial coefficients matrix (a reference to the array will be stored)

s - raw tesseral-sectorial coefficients matrix (a reference to the array will be stored)

name - name of the file (or zip entry)

Throws:

OrekitException - if a coefficient is missing

getMaxAvailableDegree

public int getMaxAvailableDegree()

Get the maximal degree available in the last file parsed.

Returns:

maximal degree available in the last file parsed

Since:

6.0

getMaxAvailableOrder

public int getMaxAvailableOrder()

Get the maximal order available in the last file parsed.

Returns:

maximal order available in the last file parsed

Since:

6.0

loadData

public abstract void loadData(InputStream input,
                              String name)
                       throws IOException,
                              ParseException,
                              OrekitException

Load data from a stream.

Specified by:

loadData in interface DataLoader

Parameters:

input - data input stream

name - name of the file (or zip entry)

Throws:

IOException - if data can't be read

ParseException - if data can't be parsed

OrekitException - if some data is missing or if some loader specific error occurs

getProvider

public abstract RawSphericalHarmonicsProvider getProvider(boolean wantNormalized,
                                                          int degree,
                                                          int order)
                                                   throws OrekitException

Get a provider for read spherical harmonics coefficients.

Parameters:

wantNormalized - if true, the provider will provide normalized coefficients, otherwise it will provide un-normalized coefficients

degree - maximal degree

order - maximal order

Returns:

a new provider

Throws:

OrekitException - if the requested maximal degree or order exceeds the available degree or order or if no gravity field has read yet

Since:

6.0

See Also:

getConstantProvider(boolean, int, int)

getConstantProvider

protected org.orekit.forces.gravity.potential.ConstantSphericalHarmonics getConstantProvider(boolean wantNormalized,
                                                                                             int degree,
                                                                                             int order)
                                                                                      throws OrekitException

Get a time-independent provider for read spherical harmonics coefficients.

Parameters:

wantNormalized - if true, the raw provider must provide normalized coefficients, otherwise it will provide un-normalized coefficients

degree - maximal degree

order - maximal order

Returns:

a new provider, with no time-dependent parts

Throws:

OrekitException - if the requested maximal degree or order exceeds the available degree or order or if no gravity field has read yet

Since:

6.0

See Also:

getProvider(boolean, int, int)

buildTriangularArray

protected static double[][] buildTriangularArray(int degree,
                                                 int order,
                                                 double value)

Build a coefficients triangular array.

Parameters:

degree - array degree

order - array order

value - initial value to put in array elements

Returns:

built array

parseDouble

protected static double parseDouble(String string)

Parse a double from a string. Accept the Fortran convention of using a 'D' or 'd' instead of an 'E' or 'e'.

Parameters:

string - to be parsed.

Returns:

the double value of string.

buildRow

protected static double[] buildRow(int degree,
                                   int order,
                                   double value)

Build a coefficients row.

Parameters:

degree - row degree

order - row order

value - initial value to put in array elements

Returns:

built row

extendListOfLists

protected void extendListOfLists(List<List<Double>> list,
                                 int degree,
                                 int order,
                                 double value)

Extend a list of lists of coefficients if needed.

Parameters:

list - list of lists of coefficients

degree - degree required to be present

order - order required to be present

value - initial value to put in list elements

toArray

protected double[][] toArray(List<List<Double>> list)

Convert a list of list into an array.

Parameters:

list - list of lists of coefficients

Returns:

a new array

parseCoefficient

protected void parseCoefficient(String field,
                                List<List<Double>> list,
                                int i,
                                int j,
                                String cName,
                                String name)
                         throws OrekitException

Parse a coefficient.

Parameters:

field - text field to parse

list - list where to put the coefficient

i - first index in the list

j - second index in the list

cName - name of the coefficient

name - name of the file

Throws:

OrekitException - if the coefficient is already set

parseCoefficient

protected void parseCoefficient(String field,
                                double[][] array,
                                int i,
                                int j,
                                String cName,
                                String name)
                         throws OrekitException

Parse a coefficient.

Parameters:

field - text field to parse

array - array where to put the coefficient

i - first index in the list

j - second index in the list

cName - name of the coefficient

name - name of the file

Throws:

OrekitException - if the coefficient is already set

rescale

protected static void rescale(double scale,
                              boolean normalizedOrigin,
                              double[][] originC,
                              double[][] originS,
                              boolean wantNormalized,
                              double[][] rescaledC,
                              double[][] rescaledS)
                       throws OrekitException

Rescale coefficients arrays.

Parameters:

scale - general scaling factor to apply to all elements

normalizedOrigin - if true, the origin coefficients are normalized

originC - cosine part of the origina coefficients

originS - sine part of the origin coefficients

wantNormalized - if true, the rescaled coefficients must be normalized

rescaledC - cosine part of the rescaled coefficients to fill in (may be the originC array)

rescaledS - sine part of the rescaled coefficients to fill in (may be the originS array)

Throws:

OrekitException - if normalization/unnormalization fails because of an underflow due to too high degree/order