10 nearest neighbors between points

2019 9 30
1 个回答
更新时间：2019 9 30
15 次查看（30 天）

0 个投票

Hi People,
I could really some help asap. I need to figure out how to modify the code proposed by MattJ (from a previous question) in order to find the 10 nearest points to every other point within a group of points (i.e., 10 nearest neighrbors). The points I speak of are the Fermat center points to the Triplets were found in the previous task. I have found all these "center points" and have their coordinates in the attached file (F_points.mat). Any help you could offer would be greatly appreciated.
Best
Steve

3 个评论
显示 1更早的评论 隐藏 1更早的评论

Walter Roberson
Walter Roberson 2019-9-30
attachment seems to be missing?
A link to the previous Question would help.
Steve
Steve 2019-9-30
Sorry about that. Here you go.
Steve
Steve 2019-9-30
编辑：Steve 2019-9-30
I would also like to plot the 10 closest points for each point with lines connecting them if possible. Thank you.

请先登录，再进行评论。

请先登录，再回答此问题。

回答（1 个）

Walter Roberson
Walter Roberson 2019-9-30

1 个投票

https://www.mathworks.com/help/stats/classification-using-nearest-neighbors.html
There is a specific routine for k-nearest-neighbour

4 个评论
显示 2更早的评论 隐藏 2更早的评论

Steve
Steve 2019-9-30
I tried using that but could not get it to work. Is there a better way?
Attached is the intermediate file needed fo the following.
Below is the code (that I acquired from MattJ) that I'm trying to make work for this new task:
close all;
clearvars;
load('F_points.mat');
% fx = F_Points{1}(2,1);
for i = 1 : 953
for j = 1 : i
fy(i) = F_points{i}(1,:);
fx(j) = F_points{j}(2,:);
end
end
FermY = fy';
FermX = fx';
X = [FermX,FermY];
thresh=1000; %distance threshold
[D,K]=pdist2(X,X,'euclidean','Smallest',10); X=X.';
K=unique( sort(K).', 'rows').'; K=K(:);
% assert(numel(unique(K))==numel(K) ,'Points not well-separated enough for threshold' );
Fs=num2cell( reshape( X(:,K), 2,10,[] ) ,[1,2]);
Fs=Fs(:).';
C=cell2mat(cellfun(@(z)mean(z,2),Fs,'uni',0) );
% imshow(IM);
hold on; plot_pts2D(flipud(C)); hold off;
Walter Roberson
Walter Roberson 2019-9-30
The "better way" is to use knnsearch . Your situation is suitable for using KDTreeSearcher
Steve
Steve 2019-9-30
I tried it and can't get it to do what I need.
Catalytic
Catalytic 2019-9-30
We can't see what you tried, and so can't know what to advise further.

请先登录，再进行评论。

类别

在 帮助中心 和 File Exchange 中查找有关 Nearest Neighbors 的更多信息

标签

提问:

Steve
Steve
2019-9-30

评论：

Catalytic
Catalytic
2019-9-30

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by