612 lines
22 KiB
C++
612 lines
22 KiB
C++
// ____ ______ __
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// / __ \ / ____// /
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// / /_/ // / / /
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// / ____// /___ / /___ PixInsight Class Library
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// /_/ \____//_____/ PCL 2.4.23
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// ----------------------------------------------------------------------------
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// pcl/JPLEphemeris.h - Released 2022-03-12T18:59:29Z
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// ----------------------------------------------------------------------------
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// This file is part of the PixInsight Class Library (PCL).
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// PCL is a multiplatform C++ framework for development of PixInsight modules.
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//
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// Copyright (c) 2003-2022 Pleiades Astrophoto S.L. All Rights Reserved.
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//
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// Redistribution and use in both source and binary forms, with or without
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// modification, is permitted provided that the following conditions are met:
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//
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// 1. All redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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//
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// 2. All redistributions in binary form must reproduce the above copyright
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// notice, this list of conditions and the following disclaimer in the
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// documentation and/or other materials provided with the distribution.
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//
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// 3. Neither the names "PixInsight" and "Pleiades Astrophoto", nor the names
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// of their contributors, may be used to endorse or promote products derived
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// from this software without specific prior written permission. For written
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// permission, please contact info@pixinsight.com.
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//
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// 4. All products derived from this software, in any form whatsoever, must
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// reproduce the following acknowledgment in the end-user documentation
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// and/or other materials provided with the product:
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//
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// "This product is based on software from the PixInsight project, developed
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// by Pleiades Astrophoto and its contributors (https://pixinsight.com/)."
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//
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// Alternatively, if that is where third-party acknowledgments normally
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// appear, this acknowledgment must be reproduced in the product itself.
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//
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// THIS SOFTWARE IS PROVIDED BY PLEIADES ASTROPHOTO AND ITS CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
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// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL PLEIADES ASTROPHOTO OR ITS
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// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
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// EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, BUSINESS
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// INTERRUPTION; PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; AND LOSS OF USE,
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// DATA OR PROFITS) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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// POSSIBILITY OF SUCH DAMAGE.
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// ----------------------------------------------------------------------------
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#ifndef __PCL_JPLEphemeris_h
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#define __PCL_JPLEphemeris_h
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/// \file pcl/JPLEphemeris.h
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#include <pcl/Defs.h>
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#include <pcl/Arguments.h>
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#include <pcl/EphemerisFile.h>
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#include <pcl/ErrorHandler.h>
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#include <pcl/KeyValue.h>
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#include <pcl/MultiVector.h>
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#include <pcl/StringList.h>
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#include <pcl/TimePoint.h>
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namespace pcl
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{
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// ----------------------------------------------------------------------------
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/*!
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* \defgroup solar_system_ephemerides Solar System Ephemerides
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*/
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/*!
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* \namespace pcl::JPLEphemerisItem
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* \brief JPL planetary ephemeris items
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*
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* Defines symbolic constants for native and derived JPL planetary ephemeris
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* items. All items defined by DE438t/LE438t are currently supported.
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*
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* <table border="1" cellpadding="4" cellspacing="0">
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* <tr><td>JPLEphemerisItem::Unknown</td> <td>Unknown ephemeris item.</td></tr>
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* <tr><td>JPLEphemerisItem::Mercury</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Venus</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::EarthMoonBarycenter</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Mars</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Jupiter</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Saturn</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Uranus</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Neptune</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Pluto</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Moon</td> <td>Geocentric Moon.</td></tr>
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* <tr><td>JPLEphemerisItem::Sun</td> <td></td></tr>
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* <tr><td>JPLEphemerisItem::Nutations</td> <td>Nutation angles dpsi and deps.</td></tr>
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* <tr><td>JPLEphemerisItem::LunarLibration</td> <td>Lunar libration angles phi, theta and psi.</td></tr>
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* <tr><td>JPLEphemerisItem::LunarMantleVelocity</td> <td>Lunar mantle velocity components omega_x, omega_y and omega_z.</td></tr>
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* <tr><td>JPLEphemerisItem::TT_TDB</td> <td>Difference TT-TDB at the geocenter in seconds</td></tr>
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* <tr><td>JPLEphemerisItem::NumberOfNativeItems</td> <td>Number of items directly available in JPL DE/LE ASCII files.</td></tr>
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* <tr><td>JPLEphemerisItem::NumberOfRequiredItems</td> <td>Number of required items in a valid JPL DE/LE ASCII file.</td></tr>
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* <tr><td>JPLEphemerisItem::Earth</td> <td>Geocenter relative to the solar system barycenter, synthesized from Earth-Moon barycenter and geocentric Moon.</td></tr>
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* <tr><td>JPLEphemerisItem::SSBMoon</td> <td>Moon relative to the solar system barycenter, synthesized from Earth-Moon barycenter and geocentric Moon.</td></tr>
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* </table>
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*
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* \ingroup solar_system_ephemerides
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*/
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namespace JPLEphemerisItem
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{
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enum value_type
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{
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Unknown = -1,
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// Native JPL DE/LE items, as of 438t
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Mercury = 0,
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Venus,
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EarthMoonBarycenter,
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Mars,
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Jupiter,
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Saturn,
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Uranus,
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Neptune,
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Pluto,
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Moon,
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Sun,
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Nutations,
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LunarLibration,
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LunarMantleVelocity,
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TT_TDB,
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NumberOfNativeItems,
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NumberOfRequiredItems = Sun + 1,
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// Special items synthesized from EMB and Moon
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Earth = 100, // Geocenter with respect to solar system barycenter
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SSBMoon = 101 // Moon with respect to solar system barycenter
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};
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}
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// ----------------------------------------------------------------------------
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/*!
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* \class JPLEphemeris
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* \brief JPL planetary ephemeris
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*
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* This class implements JPL DE/LE planetary ephemerides computed from original
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* files in ASCII format. On the PixInsight/PCL platform, this is a utility
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* class used to generate truncated binary ephemeris files in XEPH format by
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* reinterpolation with Chebyshev polynomials from the original ephemeris data.
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*
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* Source JPL ephemeris ASCII files, documentation, and original test and
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* utility programs and examples, are available at:
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*
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* ftp://ssd.jpl.nasa.gov/pub/eph/planets/
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*
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* \ingroup solar_system_ephemerides
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*
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* \sa EphemerisFile
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*/
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class JPLEphemeris
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{
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public:
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/*!
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* Represents an ephemeris item. See the JPLEphemerisItem namespace for a
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* list of the available items.
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*/
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typedef JPLEphemerisItem::value_type item_index;
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/*!
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* Represents a numerical integration ephemeris constant defined by its
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* name and value.
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*/
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typedef EphemerisConstant constant;
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/*!
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* Represents a list of integration ephemeris constants.
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*/
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typedef EphemerisConstantList constant_list;
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/*!
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* Constructs a &JPLEphemeris instance initialized from the specified DE/LE
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* ephemeris header file in ASCII format.
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*
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* In the event of errors or invalid header data, this constructor throws
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* the appropriate Error exceptions.
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*/
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JPLEphemeris( const String& filePath );
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/*!
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* Adds new ephemeris Chebyshev coefficients from the specified JPL DE/LE
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* ephemeris data file in ASCII format.
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*
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* If this is not the first call to this member function for this object,
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* the specified data file must cover a time span contiguous to the existing
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* coefficients, that is, you must call this function successively with a
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* list of consecutive ephemeris data files. For example, for DE/LE 432, you
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* can call this function in sequence for the following file names:
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*
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* ascp01550.432, ascp01650.432, ascp01750.432, ..., ascp02550.432
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*
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* to cover the entire ephemeris time span from JDE 2287184.5 to 2688976.5.
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* You can also call this function to load a smaller time span; for example,
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* calling it with the two file names:
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*
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* ascp02050.432, ascp02150.432
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*
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* will cover a limited range from JDE 2469776.5 to 2542864.5.
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*/
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void AddData( const String& filePath );
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#ifndef __PCL_NO_JPL_EPHEMERIS_TEST_ROUTINES
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/*!
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* Verifies validity of the calculated ephemerides for a standard JPL DE/LE
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* test file in ASCII format. Returns true iff the test was performed and it
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* was successful.
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*
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* A test is successful if the computed coordinates and components do not
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* differ from the values provided by the test file by more than 1e-13 in
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* absolute value. If this member function returns true, you can be
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* confident that the ephemerides being calculated with this object are
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* correct.
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*
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* The specified file must be a standard "testpo" JPL ephemeris file
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* corresponding to the DE/LE ephemeris loaded by this object. For example,
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* for DE/LE 432, the required test file is "testpo.432".
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*
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* The test is only performed within the time span covered by this object,
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* and unavailable target and center items are ignored. See the AddData()
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* member function for more information.
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*
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* If the \a verbose argument is \c true, the function will output
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* diagnostics information to stdout.
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*/
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bool Test( const String& filePath, bool verbose = true ) const;
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#endif // !__PCL_NO_JPL_EPHEMERIS_TEST_ROUTINES
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/*!
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* Returns the DE (Development Ephemeris) number for the data loaded by this
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* object. The returned number is the value of the "DENUM" integration
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* constant.
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*/
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int DENumber() const
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{
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return TruncInt( ConstantValue( "DENUM" ) );
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}
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/*!
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* Returns the LE (Lunar Ephemeris) number for the data loaded by this
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* object. The returned number is the value of the "LENUM" integration
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* constant.
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*/
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int LENumber() const
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{
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return TruncInt( ConstantValue( "LENUM" ) );
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}
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/*!
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* Returns a Julian date corresponding to the first date covered by the JPL
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* ephemeris for which this object has been initialized.
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*
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* The value returned by this function is for informative purposes only.
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* Note that the ephemeris time span does not have to be the same as the
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* effective time span covered by the data loaded in this object. See the
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* AddData() member function for more information on ephemeris data.
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*/
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double EphemerisStartJD() const
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{
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return m_ephStartJD;
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}
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/*!
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* Returns a Julian date corresponding to the last date covered by the JPL
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* ephemeris for which this object has been initialized.
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*
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* The value returned by this function is for informative purposes only.
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* Note that the ephemeris time span does not have to be the same as the
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* effective time span covered by the data loaded in this object. See the
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* AddData() member function for more information on ephemeris data.
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*/
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double EphemerisEndJD() const
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{
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return m_ephEndJD;
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}
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/*!
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* Returns a Julian date corresponding to the first date covered by the
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* ephemeris data loaded in this object.
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*
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* The value returned by this function is the smallest time point for which
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* this object can compute ephemerides. The effective ephemeris time span is
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* defined by the data loaded in successive calls to AddData().
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*/
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double StartJD() const
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{
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return m_startJD;
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}
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/*!
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* Returns a Julian date corresponding to the last date covered by the
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* ephemeris data loaded in this object.
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*
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* The value returned by this function is the largest time point for which
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* this object can compute ephemerides. The effective ephemeris time span is
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* defined by the data loaded in successive calls to AddData().
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*/
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double EndJD() const
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{
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return m_endJD;
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}
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/*!
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* Returns a reference to the list of numerical integration constants used
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* by this DE/LE ephemeris. The integration constants are loaded from an
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* ASCII header file by the class constructor.
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*
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* The returned list is sorted by constant name in ascending order.
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*/
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const constant_list& Constants() const
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{
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return m_constants;
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}
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/*!
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* Returns the value of an integration constant given by its \a name.
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*
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* If no integration constant is available with the specified \a name
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* (case-insensitive), this function throws an Error exception.
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*/
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double ConstantValue( const IsoString& name ) const
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{
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constant_list::const_iterator i =
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BinarySearch( m_constants.Begin(), m_constants.End(), EphemerisConstant( name ) );
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if ( i == m_constants.End() )
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throw Error( "Undefined integration constant '" + name + '\'' );
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return i->value;
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}
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/*!
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* Returns true if the specified ephemeris item is available in the data
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* loaded by this object. See the JPLEphemerisItem namespace for information
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* on ephemeris items.
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*/
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bool IsItemAvailable( int i ) const
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{
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if ( i == JPLEphemerisItem::Earth || i == JPLEphemerisItem::SSBMoon )
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return IsItemAvailable( JPLEphemerisItem::EarthMoonBarycenter ) && IsItemAvailable( JPLEphemerisItem::Moon );
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return i >= 0 && i < JPLEphemerisItem::NumberOfNativeItems && m_blockIndex[i].subblocks > 0;
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}
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/*!
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* Returns the number of components calculated for the specified ephemeris
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* item:
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*
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* 3 for the position and velocity of all major solar system bodies: Sun,
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* Mercury to Pluto, and Moon.
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*
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* 2 for nutation angles.
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*
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* 3 for lunar libration angles and lunar mantle velocity.
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*
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* 1 for the difference TT-TDB.
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*/
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static int ComponentsForItem( int i )
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{
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return (i == JPLEphemerisItem::Nutations) ? 2 : (i == JPLEphemerisItem::TT_TDB ? 1 : 3);
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}
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/*!
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* Computes a state vector.
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*
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* \param[out] r Reference to a vector where the components of the
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* computed state will be stored.
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*
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* \param jd1,jd2 The requested time point in the TDB time scale, equal
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* to jd1+jd2.
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*
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* \param i Index of the requested ephemeris item.
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*
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* Rectangular position coordinates are provided in au, except for the
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* geocentric Moon, whose position is provided in km.
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*
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* Angles are provided in radians.
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*
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* TT-TDB differences are provided in seconds.
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*/
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void ComputeState( Vector& r, double jd1, double jd2, item_index i ) const
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{
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if ( i == JPLEphemerisItem::Earth )
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{
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Vector rm( 3 );
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Interpolate( r.Begin(), nullptr, jd1, jd2, JPLEphemerisItem::EarthMoonBarycenter );
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Interpolate( rm.Begin(), nullptr, jd1, jd2, JPLEphemerisItem::Moon );
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rm *= m_emb2Earth;
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r -= rm;
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}
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else if ( i == JPLEphemerisItem::SSBMoon )
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{
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Vector re( 3 );
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Interpolate( re.Begin(), nullptr, jd1, jd2, JPLEphemerisItem::EarthMoonBarycenter );
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Interpolate( r.Begin(), nullptr, jd1, jd2, JPLEphemerisItem::Moon );
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r += re - m_emb2Earth*r;
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}
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else
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Interpolate( r.Begin(), nullptr, jd1, jd2, i );
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if ( i != JPLEphemerisItem::Moon )
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if ( i != JPLEphemerisItem::LunarLibration )
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if ( i != JPLEphemerisItem::Nutations )
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r *= m_km2au;
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}
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/*!
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* Computes a state vector and its first derivative.
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*
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* \param[out] r Reference to a vector where the components of the
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* computed state will be stored.
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*
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* \param[out] v Reference to a vector where the components of the
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* computed first derivative will be stored.
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*
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* \param jd1,jd2 The requested time point in the TDB time scale, equal
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* to jd1+jd2.
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*
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* \param i Index of the requested ephemeris item.
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*
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* Rectangular position and velocity coordinates are provided in au and
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* au/day, respectively, except for the geocentric Moon, whose position and
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* velocity are provided in km and km/day, respectively.
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*
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* Angles and their variations are provided in radians and radians/day.
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*
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* TT-TDB differences and their variations are provided in seconds and
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* seconds/day.
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*/
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void ComputeState( Vector& r, Vector& v, double jd1, double jd2, item_index i ) const
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{
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if ( i == JPLEphemerisItem::Earth )
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{
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Vector rm( 3 ), vm( 3 );
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Interpolate( r.Begin(), v.Begin(), jd1, jd2, JPLEphemerisItem::EarthMoonBarycenter );
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Interpolate( rm.Begin(), vm.Begin(), jd1, jd2, JPLEphemerisItem::Moon );
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rm *= m_emb2Earth;
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vm *= m_emb2Earth;
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r -= rm;
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v -= vm;
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}
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else if ( i == JPLEphemerisItem::SSBMoon )
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{
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Vector re( 3 ), ve( 3 );
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Interpolate( re.Begin(), ve.Begin(), jd1, jd2, JPLEphemerisItem::EarthMoonBarycenter );
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Interpolate( r.Begin(), v.Begin(), jd1, jd2, JPLEphemerisItem::Moon );
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r += re - m_emb2Earth*r;
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v += ve - m_emb2Earth*v;
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}
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else
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Interpolate( r.Begin(), v.Begin(), jd1, jd2, i );
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if ( i != JPLEphemerisItem::Moon )
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if ( i != JPLEphemerisItem::LunarLibration )
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if ( i != JPLEphemerisItem::Nutations )
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{
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r *= m_km2au;
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v *= m_km2au;
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}
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}
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/*!
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* Computes a state vector for the specified time coordinate \a t.
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*
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* Calling this member function is equivalent to:
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*
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|
* \code ComputeState( r, t.JDI(), t.JDF(), i ); \endcode
|
|
*/
|
|
void ComputeState( Vector& r, TimePoint t, item_index i ) const
|
|
{
|
|
ComputeState( r, t.JDI(), t.JDF(), i );
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|
}
|
|
|
|
/*!
|
|
* Computes a state vector and its first derivative for the specified time
|
|
* coordinate \a t.
|
|
*
|
|
* Calling this member function is equivalent to:
|
|
*
|
|
* \code ComputeState( r, v, t.JDI(), t.JDF(), i ); \endcode
|
|
*/
|
|
void ComputeState( Vector& r, Vector& v, TimePoint t, item_index i ) const
|
|
{
|
|
ComputeState( r, v, t.JDI(), t.JDF(), i );
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|
}
|
|
|
|
/*!
|
|
* Generates a summary of the ephemeris loaded by this object, giving
|
|
* information on general ephemeris properties and a list of integration
|
|
* constants.
|
|
*
|
|
* The generated information is organized as a sequence of text lines
|
|
* terminated with UNIX end-of-line characters.
|
|
*/
|
|
IsoString Summary() const;
|
|
|
|
private:
|
|
|
|
struct block_index_item
|
|
{
|
|
int offset = 0; // offset of this ephemeris item in a block
|
|
int coefficients = 0; // number of coefficients per subblock
|
|
int subblocks = 0; // number of subblocks
|
|
};
|
|
|
|
typedef Array<block_index_item> block_index;
|
|
|
|
typedef MultiVector block_list;
|
|
|
|
double m_ephStartJD = 0; // ephemeris start time
|
|
double m_ephEndJD = 0; // ephemeris end time
|
|
int m_blockDelta = 0; // block time span in days
|
|
constant_list m_constants; // integration constants
|
|
block_index m_blockIndex; // coefficients block index
|
|
block_list m_blocks; // coefficients blocks
|
|
double m_startJD = 0; // start time of the first coefficients block
|
|
double m_endJD = 0; // end time of the last coefficients block
|
|
double m_km2au = 0; // astronomical unit in kilometers
|
|
double m_emb2Earth = 0; // scale factor for translation Earth-Moon barycenter -> Earth
|
|
|
|
/*!
|
|
* \internal
|
|
* Chebyshev polynomial evaluation. Special function adapted to work
|
|
* directly with JPL DE/LE ephemeris data.
|
|
*/
|
|
void Interpolate( double* r, double* v, double jd1, double jd2, item_index n ) const
|
|
{
|
|
// block index
|
|
int ix = TruncInt( ((jd1 - m_startJD) + jd2)/m_blockDelta );
|
|
if ( ix < 0 || ix > int( m_blocks.Length() ) )
|
|
throw Error( String().Format( "Time point out of range: %.15g", jd1+jd2 ) );
|
|
if ( ix == int( m_blocks.Length() ) )
|
|
--ix;
|
|
|
|
// block coefficients
|
|
const double* block = m_blocks[ix].Begin();
|
|
|
|
// block index item
|
|
const block_index_item& index = m_blockIndex[n];
|
|
|
|
// block starting time
|
|
double jd0 = *block;
|
|
|
|
// number of components
|
|
int nv = ComponentsForItem( n );
|
|
|
|
// number of coefficients per subblock
|
|
int nk = index.coefficients;
|
|
|
|
// subblock time span in days
|
|
int dx = m_blockDelta/index.subblocks;
|
|
|
|
// subblock index
|
|
ix = ((jd1 - jd0) + jd2)/dx;
|
|
if ( ix == index.subblocks )
|
|
--ix;
|
|
|
|
// subblock coefficients
|
|
const double* k = block + index.offset + ix*nv*nk;
|
|
|
|
// compute state variables
|
|
Vector pc( nk );
|
|
pc[0] = 1;
|
|
pc[1] = (2*((jd1 - (jd0 + ix*dx)) + jd2) - dx)/dx;
|
|
double y2 = 2*pc[1];
|
|
for ( int i = 2; i < nk; ++i )
|
|
pc[i] = y2*pc[i-1] - pc[i-2];
|
|
for ( int i = 0; i < nv; ++i )
|
|
{
|
|
r[i] = 0;
|
|
for ( int j = 0; j < nk; ++j )
|
|
r[i] += pc[j] * *k++;
|
|
}
|
|
|
|
// if requested, compute first derivatives.
|
|
if ( v != nullptr )
|
|
{
|
|
double vf = 2.0*index.subblocks/m_blockDelta;
|
|
Vector vc( nk );
|
|
vc[0] = 0;
|
|
vc[1] = 1;
|
|
vc[2] = 2*y2;
|
|
for ( int i = 3; i < nk; ++i )
|
|
vc[i] = y2*vc[i-1] + 2*pc[i-1] - vc[i-2];
|
|
for ( int i = nv; --i >= 0; )
|
|
{
|
|
v[i] = 0;
|
|
for ( int j = nk; --j >= 0; )
|
|
v[i] += vc[j] * *--k;
|
|
v[i] *= vf;
|
|
}
|
|
}
|
|
}
|
|
};
|
|
|
|
// ----------------------------------------------------------------------------
|
|
|
|
} // pcl
|
|
|
|
#endif // __PCL_JPLEphemeris_h
|
|
|
|
// ----------------------------------------------------------------------------
|
|
// EOF pcl/JPLEphemeris.h - Released 2022-03-12T18:59:29Z
|