Program to find the k - nearest neighbors (kNN) within a set of points.
Distance metric used: Euclidean distance
[neighbors distances] = kNearestNeighbors(dataMatrix, queryMatrix, k);
dataMatrix (N x D) - N vectors with dimensionality D (within which we search for the nearest neighbors)
queryMatrix (M x D) - M query vectors with dimensionality D
k (1 x 1) - Number of nearest neighbors desired
a = [1 1; 2 2; 3 2; 4 4; 5 6];
b = [1 1; 2 1; 6 2];
[neighbors distances] = kNearestNeighbors(a,b,2);
This thing is pure brute force. Not suitable for large data sets and/or numbers of queries.
i am not able to run this file. It shows the following error:
Error using kNearestNeighbors (line 29)
Not enough input arguments.
how to use KNN in one-dimension feature?
i need code for intrusion detection using k-nearest neighbor and neural network in matlab. thanks
thank's a lot
hello, I am imputing some square matrices, but this algorithm is not working. I though that as long as D is the same for both matrices, this would work. Does that mean that N cannot be equal to M at all???
thanks in advance!!!!!!!
good efficient code , can be added group so return group selected by the indexes and make majority voting with distance weight
Ydec = ArgMax(group(i)/Dist(i))
i need code for r-nearest neightbour using sliding window concept start form window 3x3 then shift until window size of image reached. All of point is grouped based on color similarity using euclidian distance. Parameter for this code is count of r-nearest neightbour ( 25 ) and minimum color distance ( 6 ). Minimum color distance is a treshold for check the similarity between the point. So all of data point which have similarity distance color < 6 is taken for make a group. Start from window 3x3, define inisialization point X then memorizaed all data point ( 25 ) which color distance < 6.
The square distance is calculated (without square root) . Take a look a this tutorial:
really nice, simple and easy - but don't you need to take the square root for distances?
Is it fast for large dataset? Is it implemented using KD-tree?
can you tell me what is sortpos() and sortval()
what is the sortpos() function in this m file
easy but effective.thankx
Very helpful! Easy understanding!
Why would this be placed in the linear algebra category?
Users must NOW include a separate query matrix. This allows more input flexibility.
Users must not include a separate query matrix. This allows more input flexibility.
Inspired: Vector Field TB, 4-Nearest Neighbor for english letter recognition using randomized partitioning., 4-Nearest Neighbor on iris recognition using randomized partitioning., K-nearest neighbor for English letter classification by doing random partition.
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