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Absolutely Stunning Plot of a Random Sequence (Picture Included)-Need Explanation

  1. Jun 28, 2012 #1
    Absolutely Stunning Plot of a "Random" Sequence (Picture Included)--Need Explanation

    So I created 10000 waves of varying heights, 50% of the waves were 2 feet, 30% 1 foot, 15% 3 feet, 4% 4 feet, and 1% 5 feet tall.

    I generated 10000 "random" numbers with the statement "=Rand()" (this generates a random number in value [0,1], then I added each of the wave's height with each of its adjacent random number to randomize the data.

    I plotted the noisy data and I got an interesting little smudge that looked very peculiar. So I tried a different type of graph "100% stacked horizontal cone" and I got the plot that is attached, that seems to have very artistic characteristics with some pseudo wave/diffraction patterns.

    See attached. Does anyone have an explanation for this?

    Edit: Can't attach excel file for some reason, but its pretty straight forward to generate it yourself in excel.

    Attached Files:

    Last edited: Jun 28, 2012
  2. jcsd
  3. Jun 29, 2012 #2


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    Re: Absolutely Stunning Plot of a "Random" Sequence (Picture Included)--Need Explanat

    If it's the Moiré pattern to the right you're referring to, this is probably down to rounding in the data. Try truncating the numbers by one or two decimal places and see if it becomes more marked.
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