Bezier curves; FindMinimum
- To: mathgroup at smc.vnet.net
- Subject: [mg22783] Bezier curves; FindMinimum
- From: dgolber at aol.com (DGolber)
- Date: Sat, 25 Mar 2000 03:58:20 -0500 (EST)
- Organization: AOL http://www.aol.com
- Sender: owner-wri-mathgroup at wolfram.com
The file below the "=====" line is a Notebook File.
What I'm doing is finding the Bezier curve that best fits a bunch of points.
(Begins and ends at the first and last points, and is horizontal there.)
Questions:
(1) Is there a package of good stuff for Bezier curves around somewhere?
(2) The thing runs very slowly. Is there a way to modify what I'm doing to run
faster?
(I could modify the "find distance from a point to the curve" to remember the
value it found the last time, since the point is the same, and the curve has
changed very little. This would speed some part of it up.)
(3) The "FindMinimum[bez7TargetFunc ...." converges very slowly indeed.
(Thousands of evaluations of the target function!) And the parameters seem to
be moving a lot, with the curve moving only a little. Seems to be some kind of
bad behavior of the functions going on. Any comments? Are there any more
parameters I can give it?
Things to make it wiser about what's going on?
Thanks
Dave Golber
==================
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-----------------------------------
David Golber dgolber at aol.com
1 Fayette Park, Cambridge MA USA
(617) 661-3670