And no, this isn't about plotting; its about calculating and collating all these damned angles.

Actually, since plotting isn't your goal, I'm not sure you'll need the angle-sort I suggested... or maybe even the local maxima search-connected. It really depends: do you need to keep two different "islands" separate?

              6     g f e d
       7       6            c b
     7   7     6     7 7 7     a
     7 9   7   6   7       7
       7 7    6  7     8   7
             6     7 7   7 7 
                       7
[download]

If you have a grid as pictured, would you want to keep the two rings of height=7 separate, or would they all be the same "contour", in terms of the angles you need to calculate? And for calculating angles, assuming the alphabet ridge were all at the same height, would you need to know that a was adjacent to b, and b adjacent to c, but a not adjacent to c (etc)? Or would you just not care about ordering and adjacency, because you just have to compute so many annoying angles?

• If adjacency doesn't matter, and you just need bands of approximately equal height, whether or not they are part of the same ring, then you don't need the local min/max searches, and you don't need the angle sorting
• If adjacency doesn't matter, but you do need to treat the two rings of 7s separately, then you'll still have to do the min/max search, but not the angle sorting
• If adjacency does matter and the rings need to be separate, then the procedure I outlined before is probably a good starting thought.

---

---

Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!

Titles consisting of a single word are discouraged, and in most cases are disallowed outright.

Read Where should I post X? if you're not absolutely sure you're posting in the right place.

Please read these before you post! —

• How do I compose an effective node title?
• How do I post a question effectively?
• Markup in the Monastery

Posts may use any of the Perl Monks Approved HTML tags:

a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr

You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)

	For:		Use:
	&		&
	<		&lt;
	>		&gt;
	[		&#91;
	]		&#93;

Link using PerlMonks shortcuts! What shortcuts can I use for linking?

See Writeup Formatting Tips and other pages linked from there for more info.