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diff --git a/funtools/doc/regdiff.html b/funtools/doc/regdiff.html deleted file mode 100644 index 29c9658..0000000 --- a/funtools/doc/regdiff.html +++ /dev/null @@ -1,71 +0,0 @@ -<!-- =defdoc regdiff regdiff n --> -<HTML> -<HEAD> -<TITLE>Differences Between Funtools and IRAF Regions</TITLE> -</HEAD> -<BODY> - -<!-- =section regdiff NAME --> -<H2><A NAME="regdiff">RegDiff:Differences Between Funtools and IRAF Regions</A></H2> - -<!-- =section regdiff SYNOPSIS --> -<H2>Summary</H2> -Describes the differences between Funtools/ds9 regions and the old IRAF/PROS -regions. - -<!-- =section regdiff DESCRIPTION --> -<H2>Description</H2> -<P> -We have tried to make Funtools regions compatible with their -predecessor, IRAF/PROS regions. For simple regions and simple boolean -algebra between regions, there should be no difference between the two -implementations. The following is a list of differences and -incompatibilities between the two: - -<UL> - -<P> -<LI>If a pixel is covered by two different regions expressions, -Funtools assigns the mask value of the <B>first</B> region that -contains that pixel. That is, successive regions <B>do not</b> -overwrite previous regions in the mask, as was the case with the -original PROS regions. This means that one must define overlapping -regions in the reverse order in which they were defined in PROS. If -region N is fully contained within region M, then N should be defined -<B>before</B> M, or else it will be "covered up" by the latter. This -change is necessitated by the use of optimized filter compilation, i.e., -Funtools only tests individual regions until a proper match is made. - -<P> -<LI> The <B>PANDA</B> region has replaced the old PROS syntax in which -a <B>PIE</B> accelerator was combined with an <B>ANNULUS</B> accelerator -using <B>AND</B>. That is, -<PRE> - ANNULUS(20,20,0,15,n=4) & PIE(20,20,0,360,n=3) -</PRE> -has been replaced by: -<PRE> - PANDA(20,20,0,360,3,0,15,4) -</PRE> -The PROS syntax was inconsistent with the meaning of the <B>AND</B> operator. - -<P> -<LI> The meaning of pure numbers (i.e., without format specifiers) in -regions has been clarified, as has the syntax for specifying coordinate -systems. See the general discussion on -<A HREF="./regions.html">Spatial Region Filtering</A> -for more information. - -</UL> - -<!-- =section regdiff SEE ALSO --> -<!-- =text See funtools(n) for a list of Funtools help pages --> -<!-- =stop --> - -<P> -<A HREF="./help.html">Go to Funtools Help Index</A> - -<H5>Last updated: November 16, 2005</H5> - -</BODY> -</HTML> |