| This is the source code repository for ERFA (Essential Routines for |
| Fundamental Astronomy). ERFA is a C library containing key algorithms for |
| astronomy, and is based on the `SOFA library <http://www.iausofa.org/>`_ published by the International |
| Astronomical Union (IAU). |
|
|
| ERFA is intended to replicate the functionality of SOFA (aside from possible |
| bugfixes in ERFA that have not yet been included in SOFA), but is licensed |
| under a three-clause BSD license to enable its compatibility with a wide |
| range of open source licenses. Permission for this release has been |
| obtained from the SOFA board, and is avilable in the ``LICENSE`` file included |
| in this source distribution. |
|
|
| Differences from SOFA |
| |
|
|
| This version of ERFA (v1.3.0) is based on SOFA version "20160503_a", with the |
| differences outlined below. |
|
|
| ERFA branding |
| ^^^^^^^^^^^^^ |
|
|
| All references to "SOFA" in the source code have been changed to ERFA, and |
| functions have the prefix ``era`` instead of ``iau``. |
|
|
| C macro prefixes |
| ^^^^^^^^^^^^^^^^ |
|
|
| All C macros used in ERFA are the same as their SOFA equivalents, but with an |
| ``ERFA_`` prefix to prevent namespace collisions. |
|
|
| Bugfixes |
| ^^^^^^^^ |
|
|
| ERFA includes smaller changes that may or may not eventually make it into SOFA, |
| addressing localized bugs or similar smaller issues: |
|
|
| * ERFA 1.4.0 and SOFA "20170420" |
|
|
| + ERFA 1.4.0 adds the ``eraVersion`` and ``eraSofaVersion`` functions to |
| determine the installed version of ERFA (and the SOFA version it is derived |
| from). |
|
|
| + ERFA 1.4.0 includes some bug fixes contributed to ERFA after 1.3.0 but |
| before 1.4.0. These were incorporated (with modification) into |
| SOFA "20170420" (without attribution) and hence these are not differences |
| between ERFA and SOFA. (See https://github.com/liberfa/erfa/issues/40 and |
| https://github.com/liberfa/erfa/issues/41) |
|
|
| * ERFA 1.3.0 and SOFA "20160503_a" |
|
|
| + There are no differences between ERFA 1.3.0 and SOFA "20160503_a". |
|
|
| * ERFA 1.2.0 and SOFA "20150209_a" |
|
|
| + Typos have been corrected in the documentation of atco13 and atio13 (see https://github.com/liberfa/erfa/issues/29). |
|
|
| Note that issues identified in ERFA should generally also be reported upstream to SOFA at sofa@ukho.gov.uk. |
|
|
| Building and installing ERFA |
| |
|
|
| To build and install a released version of ERFA in your OS's standard |
| location, simply do:: |
| |
| ./configure |
| make |
| make install |
| |
| If you want to run the tests to make sure ERFA built correctly, before |
| installing do:: |
| |
| make check |
| |
| |
| For developers |
| ^^^^^^^^^^^^^^ |
| |
| If you are using a developer version from github, you will need to first do |
| ``./bootstrap.sh`` before the above commands. This requires ``autoconf`` and |
| ``libtool``. |
| |
| If you wish to build against the ERFA static library without installing, you |
| will find it in ``$ERFAROOT/src/.libs/liberfa.a`` after running ``make``. |
| |
| Creating a single-file version of the source code |
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |
| |
| Alternatively, if you wish to bundle the ERFA source code with a separate |
| package, you can use the ``source_flattener.py`` script from the |
| `erfa-fetch repository`_ to combine |
| the ERFA source code into just two files: a ``erfa.c`` source file, and an |
| ``erfa.h`` include file. You should run this script like this:: |
| |
| cd /path/to/erfa-source-code |
| python /path/to/erfa-fetch/source_flattener.py src -n erfa |
| |
| If possible, however, it is recommended that you provide an option to use any |
| copy of the ERFA library that is already installed on the system. |
| |
| Travis build status |
| ------------------- |
| .. image:: https://travis-ci.org/liberfa/erfa.png |
| :target: https://travis-ci.org/liberfa/erfa |
| |
| .. _erfa-fetch repository: https://github.com/liberfa/erfa-fetch |
| |
