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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 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> +<!--Converted with LaTeX2HTML 97.1 (release) (July 13th, 1997) + by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds +* revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan +* with significant contributions from: + Jens Lippman, Marek Rouchal, Martin Wilck and others --> +<HTML> +<HEAD> +<TITLE>Objectives</TITLE> +<META NAME="description" CONTENT="Objectives"> +<META NAME="keywords" CONTENT="sun67"> +<META NAME="resource-type" CONTENT="document"> +<META NAME="distribution" CONTENT="global"> +<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso_8859_1"> +<LINK REL="STYLESHEET" HREF="sun67.css"> +<LINK REL="next" HREF="node7.html"> +<LINK REL="previous" HREF="node5.html"> +<LINK REL="up" HREF="node2.html"> +<LINK REL="next" HREF="node7.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html305" HREF="node7.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html303" HREF="node2.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html297" HREF="node5.html"> +<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif.gif"></A> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0" + SRC="contents_motif.gif"></A> +<BR> +<B> Next:</B> <A NAME="tex2html306" HREF="node7.html">Fortran Version</A> +<BR> +<B>Up:</B> <A NAME="tex2html304" HREF="node2.html">INTRODUCTION</A> +<BR> +<B> Previous:</B> <A NAME="tex2html298" HREF="node5.html">Scope</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION00024000000000000000"> +Objectives</A> +</H2> +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: +<UL> +<LI> Readily available, including source code and documentation. +<LI> Supported and maintained. +<LI> Portable - coded in standard languages and available for +multiple computers and operating systems. +<LI> Thoroughly commented, both for maintainability and to +assist those wishing to cannibalize the code. +<LI> Stable. +<LI> Trustworthy - some care has gone into +testing SLALIB, both by comparison with published data and +by checks for internal consistency. +<LI> Rigorous - corners are not cut, +even where the practical consequences would, as a rule, be +negligible. +<LI> Comprehensive, without including too many esoteric features +required only by specialists. +<LI> Practical - almost all the routines have been written to +satisfy real needs encountered during the development of +real-life applications. +<LI> Environment-independent - the package is +completely free of pauses, stops, I/O <I>etc</I>. +<LI> Self-contained - SLALIB calls no other libraries. +</UL> +A few <I>caveats</I>: +<UL> +<LI> 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. +<LI> 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. +<LI> There are omissions - for example there are no +routines for calculating physical ephemerides of +Solar-System bodies. +<LI> SLALIB is not homogeneous, though important subsets +(for example the FK4/FK5 routines) are. +<LI> The library is not foolproof. You have to know what +you are trying to do (<I>e.g.</I> 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). +<LI> 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. +</UL> +<BR> <HR> +<A NAME="tex2html305" HREF="node7.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html303" HREF="node2.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html297" HREF="node5.html"> +<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif.gif"></A> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0" + SRC="contents_motif.gif"></A> +<BR> +<B> Next:</B> <A NAME="tex2html306" HREF="node7.html">Fortran Version</A> +<BR> +<B>Up:</B> <A NAME="tex2html304" HREF="node2.html">INTRODUCTION</A> +<BR> +<B> Previous:</B> <A NAME="tex2html298" HREF="node5.html">Scope</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<ADDRESS> +<I>SLALIB --- Positional Astronomy Library<BR>Starlink User Note 67<BR>P. T. Wallace<BR>12 October 1999<BR>E-mail:ptw@star.rl.ac.uk</I> +</ADDRESS> +</BODY> +</HTML> |