find the minimum distances of all points from neighboring points

When there are a lot of points, I want to find the minimum distances of all points from neighboring points.

It's too slow right now because there are so many dots.

distances = [];
for i = 1:k   
    for j = 1:k
        if i==j
            distances(i,j) = 100000; 
        else
            distances(i,j) = pdist2(blobMeasurements(i).Centroid, blobMeasurements(j).Centroid);
        end
    end
end

[distances_min, distances_min_index] = min(distances); 

I need to find the distance from a point to the nearest point

Also, I have to calculate this process for every point.

Is there a good way?

Answer 1

[darova]

Program is slow because of pre-allocation and calling pdist2 everytime

try this

D = pdist2(centroid,centroid);

D = D + eye(size(D))*1E5;

Answer 2

[Sulaymon Eshkabilov]

Here is a nice discussion on this issue with some well developed scripts:

https://www.mathworks.com/matlabcentral/answers/309497-finding-minimum-distance-between-two-points?s_tid=answers_rc1-2_p2_MLT

[HJ]

It's a good resource, but the content is different.

I need to find the distance from a point to the nearest point

Also, I have to calculate this process for every point.