Nearest Neighbor Search: Python

Question

I have a 2 dimensional array:

MyArray = array([6588252.24, 1933573.3, 212.79, 0, 0],
                [6588253.79, 1933602.89, 212.66, 0, 0],
                 etc         


        

Answer 1

Thanks to John Vinyard for suggesting scipy. After some good research and testing, here is the solution to this question:

Prerequisites: Install Numpy and SciPy

1. Import the SciPy and Numpy Modules

2. Make a copy of the 5 dimensional array including just the X and Y values.

3. Create an instance of a cKDTree as such:

   YourTreeName = scipy.spatial.cKDTree(YourArray, leafsize=100)
   #Play with the leafsize to get the fastest result for your dataset
   

4. Query the cKDTree for the Nearest Neighbor within 6 units as such:

   for item in YourArray:
       TheResult = YourTreeName.query(item, k=1, distance_upper_bound=6)
   

   for each item in YourArray, TheResult will be a tuple of the distance between the two points, and the index of the location of the point in YourArray.