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Help with fractal dimensions!

  1. Jan 25, 2012 #1
    First post!

    I'm investigating chaos in non linear coupled spring oscillators. After generating a poincare' map of said system i wanted to see if the map was fractal. i proceeded to use a box counting method in order to calculate a fractal dimension.

    I generated a plot of log(number of occupied boxes) versus log(total boxes) and the slope should be the fractal dimension, i think. However my slope was approximately .65

    Is this acceptable? I've only seen fractal dimensions of values between 1 and 2. Which leads me to believe i've done something wrong. any help?

    also if i posted in the wrong place i apologize in advance.
  2. jcsd
  3. Jan 25, 2012 #2


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    should be more than 1. Dont you need to guarantee that the structures in each box are self-similar?
  4. Jan 25, 2012 #3


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    I think this is more appropriate for your data:


    where e is the s box size
  5. Jan 25, 2012 #4
    thanks for the reply

    i plotted log(1/e) on the x-axis and log(N(e)) on the y-axis, making the slope D

    in terms of taking the limit as the box approaches zero: my poincare' map has a limited resolution (number of data points taken) and at small box sizes the total number of occupied boxes will only approach the max number of data points.

    my plot of log(1/e) on the x-axis and log(N(e)) on the y-axis shows this because at small box sizes the slope approaches 0.
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