Cluster analysis or clustering is the task of grouping a set of objects in such a way that objects in the same group (called a cluster) are more similar (in some sense or another) to each other than to those in other groups (clusters).
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31 views
Calculating Euclidean norm for each vector in a sparse matrix
Below is a naive algorithm to find nearest neighbours for a point in some n-dimensional space.
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1answer
77 views
K-nearest neighbours in MATLAB
I implemented K-Nearest Neighbours algorithm, but my experience using MATLAB is lacking. I need you to check the small portion of code and tell me what can be improved or modified. I hope it is a ...
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1answer
58 views
KMeans in the shortest and most readable format
I'm learning Python (coming from Java) so I decided to write KMeans as a practice for the language. However I want to see how could one improve the code and making it shorter and yet readable. I ...
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1answer
70 views
Nearest pair of points
Given a set of 2 dimensional points, it returns the two nearest points. If more pairs have the same min-distance between them, then an arbitrary choice is made. This program expects the points to be ...
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1answer
529 views
String Matching and Clustering
I have a pretty simple problem. A large set of unique strings that are to various degrees not clean, and in reality they in fact represent the same underlying reality. They are not person names, but ...
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3answers
267 views
How to speed up this k-nearest neighbors code?
I have implemented kNN (k-nearest neighbors) as following, but it is very slow. I want to get an exact k-nearest-neighbor, not the approximate ones, so I didn't use the FLANN or ANN libraries. Could ...
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2answers
893 views
Is this the fastest way to find the closest point to a list of points using numpy?
I'm trying to find the closest point (Euclidean distance) from a user inputed point to a list of 50,000 points that I have. Note that the list of points changes all the time. and the closest distance ...
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3answers
329 views
Nearest Neighbour classification algorithm
The following code is from a university assignment of mine to write a classification algorithm (using nearest neighbour) to classify whether or not a given feature set (each feature is the frequency ...
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4answers
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Grouping consecutive numbers into ranges in Python 3.2
The following is a function that I wrote to display page numbers as they appear in books.
If you enter the list [1,2,3,6,7,10], for example, it would return:
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Is this a BSP tree? Am I missing something?
I've been practicing using BSP trees as I hear they are a good start to create procedural spaces such as houses.
For ease-of-deployment purposes, I've tested this code in Lua and it seems to work. ...
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164 views
A sophisticated algorithm for geometric computation (distance between points) [closed]
I am confused by an algorithm for counting the number of pairs of N random points which has a distance closer than d = sqrt((p1.x-p2.x)^2 + (p1.y-p2.y)^2)
The ...
