Package org.orekit.forces.gravity.potential

Class SHAFormatReader

java.lang.Object

org.orekit.forces.gravity.potential.PotentialCoefficientsReader

org.orekit.forces.gravity.potential.SHAFormatReader

All Implemented Interfaces:

DataLoader

public class SHAFormatReader
extends PotentialCoefficientsReader

Reader for the SHA gravity field format.

This format is used by some lunar gravity models distributed by NASA's Planetary Geology, Geophysics and Geochemistry Laboratory such as GRGM1200B and GRGM1200L. It is a simple ASCII format, described in the GRGM1200B model product site. The first line contains 4 constants: model GM, mean radius, maximum degree and maximum order. All other lines contain 6 entries: degree, order, Clm, Slm, sigma Clm and sigma Slm (formal errors of Clm and Slm).

The proper way to use this class is to call the GravityFieldFactory which will determine which reader to use with the selected gravity field file.

Author:

Rafael Ayala

See Also:

GravityFields

Constructor Summary

Constructors

Constructor	Description
SHAFormatReader(String supportedNames, boolean missingCoefficientsAllowed)	Simple constructor.

Method Summary

Modifier and Type	Method	Description
RawSphericalHarmonicsProvider	getProvider(boolean wantNormalized, int degree, int order)	Provider for read spherical harmonics coefficients.
void	loadData(InputStream input, String name)	Load data from a stream.

Methods inherited from class org.orekit.forces.gravity.potential.PotentialCoefficientsReader

buildFlatArray, buildRow, getAe, getBaseProvider, getMaxAvailableDegree, getMaxAvailableOrder, getMaxParseDegree, getMaxParseOrder, getMu, getSupportedNames, getTideSystem, missingCoefficientsAllowed, parseCoefficient, parseDouble, rescale, rescale, setAe, setMaxParseDegree, setMaxParseOrder, setMu, setRawCoefficients, setReadComplete, setTideSystem, stillAcceptsData, toDate, toDate

Methods inherited from class java.lang.Object

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

Constructor Detail

SHAFormatReader

public SHAFormatReader(String supportedNames,
                       boolean missingCoefficientsAllowed)

Simple constructor.

Parameters:

supportedNames - regular expression for supported files names

missingCoefficientsAllowed - if true, allows missing coefficients in the input data

Since:

12.2

Method Detail

loadData

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

Load data from a stream.

Specified by:

loadData in interface DataLoader

Specified by:

loadData in class PotentialCoefficientsReader

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 or if some loader specific error occurs

OrekitException

getProvider

public RawSphericalHarmonicsProvider getProvider(boolean wantNormalized,
                                                 int degree,
                                                 int order)

Provider for read spherical harmonics coefficients. Like EGM fields, SHA fields don't include time-dependent parts, so this method returns directly a constant provider.

Specified by:

getProvider in class PotentialCoefficientsReader

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

Since:

12.2