资料来源 : pyDict
分数维几何,分形
资料来源 : WordNet®
fractal
n : (mathematics) a geometric pattern that is repeated at every
scale and so cannot be represented by classical geometry
资料来源 : Free On-Line Dictionary of Computing
fractal
A fractal is a rough or fragmented
geometric shape that can be subdivided in parts, each of which
is (at least approximately) a smaller copy of the whole.
Fractals are generally self-similar (bits look like the whole)
and independent of scale (they look similar, no matter how
close you zoom in).
Many mathematical structures are fractals; e.g. {Sierpinski
triangle}, {Koch snowflake}, {Peano curve}, {Mandelbrot set}
and {Lorenz attractor}. Fractals also describe many
real-world objects that do not have simple geometric shapes,
such as clouds, mountains, turbulence, and coastlines.
{Benoit Mandelbrot}, the discoverer of the {Mandelbrot set},
coined the term "fractal" in 1975 from the Latin fractus or
"to break". He defines a fractal as a set for which the
{Hausdorff Besicovich dimension} strictly exceeds the
{topological dimension}. However, he is not satisfied with
this definition as it excludes sets one would consider
fractals.
{sci.fractals FAQ
(ftp://src.doc.ic.ac.uk/usenet/usenet-by-group/sci.fractals/)}.
See also {fractal compression}, {fractal dimension}, {Iterated
Function System}.
{Usenet} newsgroups: {news:sci.fractals},
{news:alt.binaries.pictures.fractals}, {news:comp.graphics}.
["The Fractal Geometry of Nature", Benoit Mandelbrot].
[Are there non-self-similar fractals?]
(1997-07-02)