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diff --git a/src/slalib/sun67.htx/node55.html b/src/slalib/sun67.htx/node55.html new file mode 100644 index 0000000..390f876 --- /dev/null +++ b/src/slalib/sun67.htx/node55.html @@ -0,0 +1,200 @@ +<!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>SLA_DFLTIN - Decode a Double Precision Number</TITLE> +<META NAME="description" CONTENT="SLA_DFLTIN - Decode a Double Precision Number"> +<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="node56.html"> +<LINK REL="previous" HREF="node54.html"> +<LINK REL="up" HREF="node13.html"> +<LINK REL="next" HREF="node56.html"> +</HEAD> +<BODY > +<BR> <HR> +<A NAME="tex2html976" HREF="node56.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html974" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html968" HREF="node54.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="tex2html977" HREF="node56.html">SLA_DH2E - Az,El to</A> +<BR> +<B>Up:</B> <A NAME="tex2html975" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html969" HREF="node54.html">SLA_DEULER - Euler Angles to Rotation Matrix</A> +<BR> <HR> <P> +<P><!--End of Navigation Panel--> +<H2><A NAME="SECTION000442000000000000000">SLA_DFLTIN - Decode a Double Precision Number</A> +<A NAME="xref_SLA_DFLTIN"> </A><A NAME="SLA_DFLTIN"> </A> +</H2> + <DL> +<DT><STRONG>ACTION:</STRONG> +<DD>Convert free-format input into double precision floating point. +<DT><STRONG>CALL:</STRONG> +<DD><TT>CALL sla_DFLTIN (STRING, NSTRT, DRESLT, JFLAG)</TT> +<P> </DL> +<P> <DL> +<DT><STRONG>GIVEN:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>STRING</EM></TD> +<TH ALIGN="LEFT"><B>C</B></TH> +<TD ALIGN="LEFT" NOWRAP>string containing number to be decoded</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>NSTRT</EM></TD> +<TD ALIGN="LEFT"><B>I</B></TD> +<TD ALIGN="LEFT" NOWRAP>pointer to where decoding is to commence</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DRESLT</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>current value of result</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>RETURNED:</STRONG> +<DD> +<BR> +<TABLE CELLPADDING=3> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>NSTRT</EM></TD> +<TH ALIGN="LEFT"><B>I</B></TH> +<TD ALIGN="LEFT" NOWRAP>advanced to next number</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>DRESLT</EM></TD> +<TD ALIGN="LEFT"><B>D</B></TD> +<TD ALIGN="LEFT" NOWRAP>result</TD> +</TR> +<TR VALIGN="TOP"><TD ALIGN="LEFT"><EM>JFLAG</EM></TD> +<TD ALIGN="LEFT"><B>I</B></TD> +<TD ALIGN="LEFT" NOWRAP>status: -1 = -OK, 0 = +OK, 1 = null result, 2 = error</TD> +</TR> +</TABLE></DL> +<P> <DL> +<DT><STRONG>NOTES:</STRONG> +<DD><DL COMPACT> +<DT>1. +<DD>The reason sla_DFLTIN has separate `OK' status values +for + and - is to enable minus zero to be detected. +This is of crucial importance + when decoding mixed-radix numbers. For example, an angle + expressed as degrees, arcminutes and arcseconds may have a + leading minus sign but a zero degrees field. + <DT>2. +<DD>A TAB is interpreted as a space, and lowercase characters are + interpreted as uppercase. <I>n.b.</I> The test for TAB is + ASCII-specific. + <DT>3. +<DD>The basic format is the sequence of fields <IMG WIDTH="78" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img68.gif" + ALT="$\pm n.n x \pm n$">, where <IMG WIDTH="15" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img30.gif" + ALT="$\pm$"> is a sign + character `+' or `-', <I>n</I> means a string of decimal digits, + `.' is a decimal point, and <I>x</I>, which indicates an exponent, + means `D' or `E'. Various combinations of these fields can be + omitted, and embedded blanks are permissible in certain places. + <DT>4. +<DD>Spaces: + <UL> +<LI> Leading spaces are ignored. +<LI> Embedded spaces are allowed only after +, -, D or E, + and after the decimal point if the first sequence of + digits is absent. +<LI> Trailing spaces are ignored; the first signifies + end of decoding and subsequent ones are skipped. + </UL> + <DT>5. +<DD>Delimiters: + <UL> +<LI> Any character other than +,-,0-9,.,D,E or space may be + used to signal the end of the number and terminate decoding. +<LI> Comma is recognized by sla_DFLTIN as a special case; it + is skipped, leaving the pointer on the next character. See + 13, below. +<LI> Decoding will in all cases terminate if end of string + is reached. + </UL> + <DT>6. +<DD>Both signs are optional. The default is +. + <DT>7. +<DD>The mantissa <I>n</I>.<I>n</I> defaults to unity. + <DT>8. +<DD>The exponent <IMG WIDTH="36" HEIGHT="25" ALIGN="MIDDLE" BORDER="0" + SRC="img69.gif" + ALT="$x\!\pm\!n$"> defaults to `D0'. + <DT>9. +<DD>The strings of decimal digits may be of any length. + <DT>10. +<DD>The decimal point is optional for whole numbers. + <DT>11. +<DD>A <I>null result</I> occurs when the string of characters + being decoded does not begin with +,-,0-9,.,D or E, or + consists entirely of spaces. When this condition is + detected, JFLAG is set to 1 and DRESLT is left untouched. + <DT>12. +<DD>NSTRT = 1 for the first character in the string. + <DT>13. +<DD>On return from sla_DFLTIN, NSTRT is set ready for the next + decode - following trailing blanks and any comma. If a + delimiter other than comma is being used, NSTRT must be + incremented before the next call to sla_DFLTIN, otherwise + all subsequent calls will return a null result. + <DT>14. +<DD>Errors (JFLAG=2) occur when: + <UL> +<LI> a +, -, D or E is left unsatisfied; or +<LI> the decimal point is present without at least + one decimal digit before or after it; or +<LI> an exponent more than 100 has been presented. + </UL> + <DT>15. +<DD>When an error has been detected, NSTRT is left + pointing to the character following the last + one used before the error came to light. This + may be after the point at which a more sophisticated + program could have detected the error. For example, + sla_DFLTIN does not detect that `1D999' is unacceptable + (on a computer where this is so) until the entire number + has been decoded. + <DT>16. +<DD>Certain highly unlikely combinations of mantissa and + exponent can cause arithmetic faults during the + decode, in some cases despite the fact that they + together could be construed as a valid number. + <DT>17. +<DD>Decoding is left to right, one pass. + <DT>18. +<DD>See also sla_FLOTIN and sla_INTIN. + </DL></DL> +<BR> <HR> +<A NAME="tex2html976" HREF="node56.html"> +<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A> +<A NAME="tex2html974" HREF="node13.html"> +<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif.gif"></A> +<A NAME="tex2html968" HREF="node54.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="tex2html977" HREF="node56.html">SLA_DH2E - Az,El to</A> +<BR> +<B>Up:</B> <A NAME="tex2html975" HREF="node13.html">SUBPROGRAM SPECIFICATIONS</A> +<BR> +<B> Previous:</B> <A NAME="tex2html969" HREF="node54.html">SLA_DEULER - Euler Angles to Rotation Matrix</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> |