README.md

Solar system ephemeris access library

Repository contents

• libephaccess is a C library for calculating planetary positions and other data from SPICE files
• ephcalculator is a command-line utility based on libephaccess
• python directory contains Python wrapper for libephaccess
• eph.sln is a MS Visual Studio solution file for libephaccess and ephcalculator
• setup.py is a Distutils setup script for the Python wrapper

Build

libephaccess

On Windows, build the solution eph.sln in Visual Studio.

On Linux or OS X, cd to the libephaccess folder and run

make CONF=<configuration>

where <configuration> is one of:

• ReleaseStatic32 (Linux 32-bit static library)
• ReleaseShared32 (Linux 32-bit shared library)
• ReleaseStatic64 (Linux 64-bit static library)
• ReleaseShared64 (Linux 64-bit shared library)
• ReleaseStatic64OSX (OS X static library)
• ReleaseShared64OSX (OS X shared library)

ephcalculator

On Windows, build the solution eph.sln in Visual Studio.

On Linux or OS X, cd to the ephcalculator folder and run

make CONF=<configuration>

where <configuration> is one of:

• Release32 (Linux 32-bit executable)
• Release64 (Linux 64-bit executable)
• Release64OSX (OS X executable)

Python wrapper for libephaccess

Direct installation from repository

Direct installation from Gitlab repository is supported for both Python 2.7 and Python 3:

pip install git+ssh://git@gitlab.iaaras.ru:10022/iaaras/ephemeris-access.git

(use pip2 or pip3 to distinguish between Python 2 and Python 3)

or

python -m pip install git+ssh://git@gitlab.iaaras.ru:10022/iaaras/ephemeris-access.git

(use python2 or python3 to distinguish between Python 2 and Python 3)

C compiler and linker are needed in the system to compile and link the C modules into a shared library. On Linux or OS X, gcc or clang should suffice. On Windows, different versions of Microsoft Visual Studio are required depending on Python major version. For Python 3, MSVS 2015 or later (including “Express” versions) is required. For Python 2, a special distribution of MSVS is required.

Manual installation

From parent folder of downloaded ephemeris-access folder, run

pip install ephemeris-access

or

python -m pip install ephemeris-access

(The above notes regarding Python 2/3 and C compiler apply here, too)

Usage without installation

ephaccess folder can be used as is, as long as it resides in the same directory as user's Python program. But the shared library still must be built beforehand, in this case with the following command:

python setup.py build_ext --inplace

(The above notes regarding C compiler apply here, too)

Usage

• For libephaccess, see the comments in the ephaccess.h file. Also, ephcalculator.c is a good example of libephaccess usage.
• For ephcalculator, a build-in help message is provided.
• For Python wrapper, see python/test.py example script.