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Array correlation

  1. Mar 27, 2008 #1
    Hi, hoping someone might be able to help as my math skills appear to be wanting.

    I'm writing some software to identify individual newts from within a population by comparing their ventral markings. Photographs of the ventral markings are loaded into the software and registered so that each newt is straight and in the same orientation. The user then clicks on a number of spots that make up the ventral marking. The x, y coordinates of these spots are then recorded in an array.

    Here's where it gets tricky. I wish to compare one array against another to identify whether or not the 2 arrays belong to the same newt - this would help in identifying a newt during recaptures. The x, y coordinates of the spots themselves are not an adequate means by which to perform this correlation as they may vary depending upon slight variation of the posture of the newt, and the spots that were selected by the user when mapping the ventral markings.

    In theory, I believe that the most reliable measurements to compare will be the angles and distances of each spot within an array to those of the other spots in the array. And so I have coded for the software to automatically calculate all of the angles and distances of the spots.

    Hopefully you're still with me, what I would now like to be able to do is to compare 2 or more arrays to see if any of the spot arrangements are found in each of the arrays which might indicate a match. Each array consists of the following values:

    x point n1.., y point n1.., x point n2.., y point n2.., angle, distance

    Hope that makes some degree of sense, and that someone might be able to offer some help.

  2. jcsd
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