Objectives

From d54fe7c1f704a63824c5bfa0ece65245572e9b27 Mon Sep 17 00:00:00 2001 From: Joseph Hunkeler Date: Wed, 4 Mar 2015 21:21:30 -0500 Subject: Initial commit --- src/slalib/sun67.htx/node6.html | 116 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) create mode 100644 src/slalib/sun67.htx/node6.html (limited to 'src/slalib/sun67.htx/node6.html') diff --git a/src/slalib/sun67.htx/node6.html b/src/slalib/sun67.htx/node6.html new file mode 100644 index 0000000..c90fd51 --- /dev/null +++ b/src/slalib/sun67.htx/node6.html @@ -0,0 +1,116 @@ + + + + +Objectives + + + + + + + + + + + + +

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+Objectives +

+SLALIB was designed to give application programmers +a basic set of positional-astronomy tools which were +accurate and easy to use. To this end, the library is: +

Readily available, including source code and documentation. +
Supported and maintained. +
Portable - coded in standard languages and available for +multiple computers and operating systems. +
Thoroughly commented, both for maintainability and to +assist those wishing to cannibalize the code. +
Stable. +
Trustworthy - some care has gone into +testing SLALIB, both by comparison with published data and +by checks for internal consistency. +
Rigorous - corners are not cut, +even where the practical consequences would, as a rule, be +negligible. +
Comprehensive, without including too many esoteric features +required only by specialists. +
Practical - almost all the routines have been written to +satisfy real needs encountered during the development of +real-life applications. +
Environment-independent - the package is +completely free of pauses, stops, I/O etc. +
Self-contained - SLALIB calls no other libraries. +

+A few caveats: +

SLALIB does not pretend to be canonical. It is in essence +an anthology, and the adopted algorithms are liable +to change as more up-to-date ones become available. +
The functions aren't orthogonal - there are several +cases of different +routines doing similar things, and many examples where +sequences of SLALIB calls have simply been packaged, all to +make applications less trouble to write. +
There are omissions - for example there are no +routines for calculating physical ephemerides of +Solar-System bodies. +
SLALIB is not homogeneous, though important subsets +(for example the FK4/FK5 routines) are. +
The library is not foolproof. You have to know what +you are trying to do (e.g. by reading textbooks on positional +astronomy), and it is the caller's responsibility to supply +sensible arguments (although enough internal validation is done to +avoid arithmetic errors). +
Without being written in a wasteful +manner, SLALIB is nonetheless optimized for maintainability +rather than speed. In addition, there are many places +where considerable simplification would be possible if some +specified amount of accuracy could be sacrificed; such +compromises are left to the individual programmer and +are not allowed to limit SLALIB's value as a source +of comparison results. +

+ +

+
+ Next: Fortran Version +
+Up: INTRODUCTION +
+ Previous: Scope +

+SLALIB --- Positional Astronomy Library
Starlink User Note 67
P. T. Wallace
12 October 1999
E-mail:ptw@star.rl.ac.uk +

+ + -- cgit