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Fractals/The Newton-Raphson fractal
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"The "flowers" are beautiful to behold but totally abhorrent from the numerical point of view." Ramilliesmath.stackexchange question : why-does-the-newton-raphson-method-not-converge-for-some-functions
The newton fractal is calculated by iterating the Newton-Raphson root finding method,Newton’s Method as a Dynamical System by Johannes Ruckert and coloring the sample point in various ways based on various properties of how the point is attracted to the various 'roots' or 'solutions' to the method. For example how fast or at what angle the orbit is attracted.
Newton Family of fractals
256px|right|thumb|An example showing the PhoenixDoubleNova Fractal, in a complex composite by Dan Wills
There has been much development using this method to develop fractal formulae in the UltraFractal formula database, and in other fractal-rendering software. One notable family of newton style fractals is the Nova fractal family, with formulae that combine aspects of other well known fractals such as Mandelbrot, Phoenix and Halley's fractal - which is another fractal that is similar to the newton in that it implements a root finding method known as Halley's method.
An entire family of fractal formulae have been derived this way and given names that reflect their parent formulae, for example:
Nova Julia
Nova Mandelbrot
Phoenix Nova
Halley Nova
Phoenix Double Nova
Phoenix Halley Nova
As the development of these fractal formula authors has been quite prolific, there are a great many variations and combinations.
Links
Wikipedia on the Newton Fractal
Newton method
3D images of Newton fractals
Newton methon in WebGl the Newton basin fractal for the polynomial . Clicking and dragging updates lambda and the resulting basins.
Root finding methods: a dynamical approach Autor: Javier Olea Mart´ınez
Examples in Python by Jürgen Meier
basins-of-attraction by Bernd Frassek using VOC
Dynamics of projectable functions: Towards an atlas of wandering domains for a family of Newton maps by Robert Florido, Núria Fagella