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Newsgroups: povray.binaries.scene-files
Date: 6th Oct 2014
From: Tor Olav Kristensen
Subject: Making functions for natural cubic splines
http://news.povray.org/povray.binaries.scene-files/thread/%3Cweb.54358f8d5b2bbe7b5e7df57c0%40news.povray.org%3E/

This image illustrates how each of 4 sets of X-, Y- and Z-functions contributes
to each of the 4 parts of a spline in between the 5 (red) points at tt[0],
tt[1], tt[3], tt[4] and tt[5].

Interval from tt[0] to tt[1]: Cyan
Interval from tt[1] to tt[2]: Green
Interval from tt[2] to tt[3]: Orange
Interval from tt[3] to tt[4]: Yellow

Each of the 12 (= 4*3) functions is a cubic polynomial.

--
Tor Olav
http://subcube.com

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